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[Articles Home]  [Add Article]  

Tube or not Tube: That is the Question

Eric P. Nichols (KL7AJ) on March 10, 2008
View comments about this article!

CHAPTER THIRTY

Tube or not Tube: That is the Question

No book about Amateur Radio, much less a book about Amateur Radio lore would be complete without a discussion of electron tubes. These glowing globes were the workhorses of all electronics equipment for most of the last century, and still have a secure position in modern Amateur Radio, as well as industry.

The electron tube, alternately known as the Valve in Great Britain, the Lamp in France, and just plain tube in a lot of other places, represents a surprising level of mechanical, chemical and electrical engineering. It was the most sophisticated piece of hardware produced in the early part of the twentieth century, except for, perhaps, the precision pocket watch.

For most of this chapter, we're going to be talking mainly about one particular variety of electron tube, the vacuum tube, a term which has often been used interchangeably but somewhat inaccurately, with electron tube. Be that as it may, it is a fascinating device in any form.

Recall that in our introduction to the electron, we dealt with electrons in conductors. We demonstrated that, though electrical energy in a conductor traveled at nearly the speed of light, the actual electron movement, or electron drift, was painfully slow.

Not so in the electron tube. The electron tube is full of free electrons, which can, indeed travel near the speed of light. You might be asking yourself how a "vacuum" tube could be full of anything, which is probably a good question. Vacuum is a relative term, in this case. But, be assured, there is indeed very little inside a vacuum tube.

Now, although the free electrons in a tube can move very fast, in most applications we keep them somewhat below the speed of light. They are non-relativistic electrons, meaning they behave pretty much as mere particles, and, for the most part, follow the standard mechanical laws of Newton. This is a good thing, because vacuum tubes are complicated enough as it is. There are "tubes" of sorts that indeed use relativistic electrons, such as the free electron laser, but you won't see many of these around the average ham shack.

So, with that background, let's get started. The first thing we need is a bottle of free electrons. A light bulb is actually such a device. An incandescent filament in a glass bottle will "boil" off a certain number of electrons. The problem with a light bulb, however, is that there's a lot of other stuff that gets in the way of our electrons. Our free electrons need a clear path to work in, and in a typical light bulb, you don't have that. You have a lot of Argon atoms clogging up the works. They put Argon in light bulbs to prevent oxidation of the filament, which is supposed to make the bulbs last a long time. Obviously, that doesn't work, so it must be a conspiracy of the Argon companies to sell a lot of Argon. Be that as it may, we have to work with our light bulb a bit to make them suitable free electron bottles.

The first thing we need to do is create a hard vacuum. It's called a hard vacuum, because it's very hard to do. We need to get EVERY atom (or ion) we can out of the thing, which you can't do by just sucking on a straw. There's a three-step process. The first is to use a mechanical vacuum pump to get the pressure down just as far as possible, then you use a diffusion pump to get the pressure down even farther. Don't even ask how a diffusion pump works; I don't even think the guy who invented it knows. They're weird looking things that sort of resemble a percolator wrapped with a tornado-shaped coil of stainless steel tubing. Anyway, with your diffusion pump, you can get the pressure down to something like what you have in intergalactic space. The last step is to seal off the tube where you put the sucker-doodle in, and then you fire off the getter. The getter is a little ring of a very reactive metallic compound, which reacts with any remaining ions inside the tube, and deposits the results on the glass envelope, in a little silvery spot. The getter is “lit” by means of a radio frequency induction heater placed outside the tube near the getter. This process itself is actually very advanced; it was probably the first industrial application of anything resembling the microwave oven. The getter will continue to pick up stray ions for the life of the tube (in theory).

So, now we have a light bulb with a hard vacuum, with lots of elbowroom for those electrons to strut their stuff. Ahh, but how do we get electrons in there in the first place, since the tube is hermetically sealed?

Well, the best source of electrons is in the metal of the filament. When the filament gets white hot (or actually just sort of reddish-orange hot in most tubes), you actually boil electrons out of the metal. Well, perhaps boil isn't the best word, but it's pretty descriptive. If you recall our chapter "Bent Radio," we learned that in the ionosphere gas atoms are ionized by getting hit with ultraviolet radiation from the Sun, which slaps the electrons out of orbit around those atoms. In a vacuum tube, it's heat that slaps the electrons out of orbit. This process is called thermionic emission because the metal the filament is made out of is ionized by heat. It's actually a rather complicated process, (and a somewhat noisy one, we might add). The main difference between a vacuum tube and the ionosphere however, is that in the tube, the ions are held firmly in place, because they are in solid form. The ions can't wander off like they can in the ionosphere.

So, now we have all these electrons free of their metallic atoms. Since they are all negatively charged, they all repel one another. Ordinarily, because of the mutual repulsion, the electrons would quickly fill the whole "bottle." But they don't.

The reason is, now that the metal filament is ionized, it has a net POSITIVE charge, which tends to pull the electrons back toward itself. So just as the ions in the ionosphere keep a sort of rein on the free electrons, the presence of the ionized filament keeps rein on the free electrons. Actually it keeps a TIGHTER rein on the free electrons, because, as mentioned above, the ions are in a solid state. As in the ionosphere, some of these free electrons recombine with their metallic mother ships; others are continually boiling off. A state of thermionic equilibrium sets in, where the average number of free electrons stays about the same. Hey, doesn't this sound an awful lot like the electron density profile of the ionosphere?

So, we now have this mob of semi-free electrons hovering around the filament. (Let's rename our filament the CATHODE, because that's a better electrical description of the element, while FILAMENT is more a physical description). This electron mob is called an electron cloud, and it has a net space charge. Sometimes space charge and electron cloud are used interchangeably, but to be really persnickety, the space charge is a property of the electron cloud.

If you were able to poke a probe into the electron cloud, you could measure a minuscule contact potential. Some tube circuits actually use this contact potential in a useful manner, but for the most part, it's a mere curiosity.

All righty then. Our one-element vacuum tube isn't particularly useful, except as a really lame light bulb. However, if we stick a metallic plate in the tube, a certain distance from the cathode, and bring an electrical lead from the plate through the glass to the outside world, we can now actually do something with our electron cloud.

Remember our ionized cathode has a net positive charge. Well, if we put an even BIGGER positive charge on our newly installed PLATE, by means of a battery between the plate and the cathode, we can pull electrons away from the cathode to the plate. (In old-fashioned radioese, this battery is called the “B” battery, and the voltage it supplies is called “B+” voltage). These electrons are actually absorbed INTO the plate and conducted out of the tube to the positive terminal of the battery. They are then forced out the negative terminal of the battery into the cathode to replenish the electron cloud. We now have a one-way electric valve, known as a DIODE. (Oh, yes, we should rename the PLATE the ANODE, because all our tube elements should end with an "ODE"). Electrons cannot flow from the Anode to the Cathode inside the tube, because the cold anode has no spare electrons of its own.

Now, there's an awful lot you can do with just a diode. It can be a power rectifier, a radio detector, a logic gate, a current limiter, a timer, even an X-RAY generator!

Before we get too carried away with our enthusiasm, however, we need to know a couple more things about the diode.

Remember we said that our electrons are non-relativistic, meaning they follow the rules of Newtonian Mechanics? Let's look into this a bit, because we have to understand this fact before we can move onto the next level.

As with ANY particle, electrons have a finite mass. A very SMALL mass, granted, but very real, nonetheless. They take TIME to accelerate from the electron cloud to the anode. You may remember from high school physics that F=MA, Force equals Mass times Acceleration. The force in this case, is electromotive force, which comes in the form of Plate Voltage. This is the voltage we supply with our external “B” battery. When a voltage is applied to the plate, the electrons slowly drift out of the electron cloud and accelerate toward the plate. But, unlike gravity, the acceleration is not constant. There is a double-whammy here. The attractive force of the plate, for a given voltage, increases drastically as you get closer to the plate. So not only do electrons accelerate on their way to the plate, but their rate of acceleration also increases during the trip! This actually turns out to be a very useful property; it just makes the math involved pretty hairy.

Let's talk about a new term, plate resistance. In the process of electrons hitting the plate, a certain amount of "friction" is involved. In fact, with enough current, the plate of a vacuum tube of any type can get very hot due to the electrons striking the surface. Actually, the plate can, under certain circumstances, get hot enough to become a cathode, which is generally not a good thing.

Several design features of tubes, however, prevent the anode from acting TOO much like a cathode, at least relative to the true cathode. First, cathodes are generally made of materials with high thermionic efficiency—that is; they emit lots of electrons at relatively low temperatures. Materials that do this are things like thoriated tungsten and barium oxide. On the other hand, anodes are made (or coated with) materials that are really lousy thermionic emitters, such as graphite. They are also made much more MASSIVE than the cathode, so they are unlikely to reach the same TEMPERATURE for a given amount of heat dissipated.

Because of the inefficiency (and subsequent heating) of electrons being absorbed by the anode in any tube, there is an equivalent resistance through a diode, just as if it were a real resistor. This is pretty straightforward "ohmic" heating. The major contributor of "plate resistance" however, is strictly due to the finite number and availability of free electrons AND the fact that they have real mass that needs to be accelerated. It is this acceleration aspect of the electrons that makes PLATE RESISTANCE very non-linear. In other words, the plate resistance not only depends on the plate voltage, but depends on it in a rather complex manner.

But let's forget the complexity of the plate resistance for a moment. We can ignore the entire hairy math aspect and STILL grasp a very important thing about this electron acceleration.

All we need to know is that the electrons start out very slow, and end up very fast. If we can grasp that, we can easily explain the next topic: amplification.

Leveraging Electrons: The Triode

Imagine for a moment that you're a lumberjack standing on a plateau above a valley. Your plateau starts to gradually roll off in front of you, almost imperceptibly, perhaps dropping only an inch every ten feet. Beyond that, it slopes down a little more steeply, two inches every ten feet. Beyond that, three inches every ten feet. Beyond that, four inches every ten feet. Five hundred feet ahead, it's sloping down at a 45 degree angle. Half a mile ahead, it makes a vertical drop to the valley floor.

You have a log you want to roll down the plateau. You give it a kick, and it starts rolling down the hill, barely accelerating, because it's only dropping an inch every ten feet. It hits a one-inch pebble after rolling ten feet and comes to a dead stop. You remove the pebble. The log starts rolling again, this time a little faster. It rolls right over another one-inch pebble, but comes to a dead stop once again, after it hits a two-inch pebble. You remove the two-inch pebble. The log starts rolling again, even faster. It rolls right over another two-inch pebble, but comes to a dead stop when it encounters a three-inch stone. You remove the three-inch stone, and the log starts rolling again. Until it hits a four-inch rock.

Being the brilliant woodsman you are, you are finally able to conclude that the farther the log rolls, the bigger the rock you need to stop the thing. In fact, once the log reaches the vertical drop off, NO boulder is big enough to stop it.

The plateau you're standing on is your cathode. The valley floor is your plate. The log rolling down the hill is an electron. The gravity that wants to make the log roll down the hill is Plate Voltage. And the pebbles that get in the way of the progress are your third tube element, the control grid.

Actually, we could, in all good conscience, end the discussion right here, as we have described the principle of amplification completely. There is really little more to say on the matter.

But we should probably talk a little about the control grid anyway.

If we insert another electrode between the cathode and the plate, we have what's called a TRIODE. The control grid can be in the form of a screen, a helix, a zig zag, or any other "porous" configuration. Its job is to act as a pebble in the path. The sooner it gets its job done, that is, the closer it is to the cathode, the more effective it is. Once the log...er...the electron builds up kinetic energy on its way to the plate, the bigger that pebble has to be to slow it down.

The way a grid slows down an electron (actually an electron mob) is that you apply a small negative voltage to it. This voltage is called a bias voltage. This small negative voltage REPELS the electrons back toward the cathode. If the grid is close enough to the cathode, it can completely cut off the flow of electrons to the plate with a small bias voltage. This condition is called, oddly enough, cutoff. If we move the grid farther toward the plate, we need more bias voltage to cut off the electron flow, because the electrons would have already been accelerated a bit. You might have cleverly deduced that the amount of bias voltage is equivalent to the size of the rock. You would have been absolutely correct!

So you see, the more speed the electrons pick up, the bigger the bias voltage necessary to stop them in their tracks.

When the grid is very close to the cathode, however, we can control a very large amount of plate current with just a tiny amount of bias voltage. This is called amplification. A little signal controls a big signal.

Now, calling this process amplification bothers lots of folks; it seems to be just the opposite. Our input (bias) signal can only REDUCE the plate current, not increase it.

The point to remember here is that the tube doesn't generate any power in the first place. Any power the tube "puts out" actually comes from our plate battery. The purpose of the triode, then, is to simply "modulate" the plate current, in accordance with our commands. We supply our commands through the control grid.

Incidentally, since the control grid is negative with respect to the cathode, zero current flows through the grid. This means that the grid draws absolutely no power. We theoretically have INFINITE power gain with such a situation!

As you might imagine, it's not so rosy in the real world, but you can still have incredible power gains with a triode.

At this time we should mention that acceleration of electrons in a vacuum tube is not really the end goal, except in some exotic applications. There is no real advantage to super high speed electrons. Our goal is controlling CURRENT, that is, the number of electrons, not their speed. However because of plate resistance we NEED to have rather high voltage in order to get usable currents. (Yes, as convoluted and contrived as plate resistance is, it still follows Ohm's Law). And since we can't have high voltage without accelerating electrons, we end up with high speed electrons anyway.

Actually, we don't want our electrons to move too slowly, or we end up running into transit time problems. If an electron takes too much time shilly-shallying on the way to the plate, it may not work very well at radio frequencies. We can reduce transit time by making the space between ALL the elements very small, while keeping the ratio of grid spacing between the cathode and the plate the same. In other words, we can scale the tube for higher frequency. But we can't go too far in this scaling business, or we end up risking arc-over, that is electric sparks jumping between elements inside the tube. Not a good thing. So we can reduce plate voltage to prevent arc- over, but guess what? Lower plate voltage means longer transit times. Hmmm...do we even begin to grasp the problem of the tube designer? We have all these conflicting requirements that need to be met. The astonishing thing is that the early tube engineers were indeed able to pull this off, using no more number-crunching power than a slide rule!

The fact of the matter is that you had a lot of the smartest people on the planet working on making tubes that ran faster, longer, and with more power. Tubes represented the culmination of all human knowledge. Until the discovery of the transistor, tubes were all we had to work with. We HAD to do it well.

Now, a tube by itself is of limited value. It has to actually work in a circuit. In the next chapter, we will talk about how tubes interact with other components. We will also introduce a few more tube elements, creating TETRODES and PENTODES.

In the meantime, next time you encounter a tube, you really should salute.

Member Comments:
This article has expired. No more comments may be added.
 
Tube or not Tube: That is the Question  
by ONAIR on March 10, 2008 Mail this to a friend!
Nice article! I disagree however, that a tube has no value outside of a circuit. I know a guy who has a load of brand new tubes in their original boxes, from the '30s, '40s, '50s and '60s. He's holding on to them because he feels that even through they are worth a nice amount of money today, someday they will be worth quite a bit more to radio buffs and collectors!
 
RE: Tube or not Tube: That is the Question  
by N3QE on March 10, 2008 Mail this to a friend!
Interesting to have the first follow-up mention tube collecting.

I personally see myself as a tube-user, not a tube-collector. Have lots of radios, most of them pretty pedestrian and not fancy, from the 50's and 60's that get used on the air and which usually strike up a pretty good conversation on 80M CW about the first rigs that everybody owned as a Novice.

But there's a real association of tube collectors, called (surprise!) the Tube Collector's Association. They have a minor web presence but most of their stuff happens off-the-web. Ludwell Sibley of the Tube Collector's Association has at least one book, "Tube Lore", that is worthwhile but maybe just a little on the deep-end side of the hobby rather than an introduction.

The vast majority of tubes out there, even in boxes, don't have much street value. Typical value is just pennies if even that for 50's/60's/70's TV-radio tubes. BUT... there are some highly-prized audio tubes and other collectible tubes that are worth money.

I personally think that collecting tubes is far more interesting when the collectors are talking about a wide variety of tubes made over most of a century, rather than some specific high-dollar-value tube made by some company in one particular factory in one particular season when the mineral being used on the black plates was particularly prime and susceptible to microphonics :-).
 
RE: Tube or not Tube: That is the Question  
by G3LBS on March 10, 2008 Mail this to a friend!
Maybe you are a 'getter' not a 'collector'?
Buffalo Gil W2/G3LBS
 
RE: Tube or not Tube: That is the Question  
by KC8ZEV on March 10, 2008 Mail this to a friend!
Great Article!!!!! Long Live the Tube!!!!

73
KC8ZEV
 
RE: Tube or not Tube: That is the Question  
by PD2R on March 10, 2008 Mail this to a friend!
Very nice article, even I could understand it, well, most of it. But hey, Im Dutch and its hard enough as it is so imagine reading it in foreign writing.
Thanks!
 
RE: Tube or not Tube: That is the Question  
by G3LBS on March 10, 2008 Mail this to a friend!
Anyway you shouldn't be a 'collector' because that's solid state you should be an anode or a plate.
I hereby define a person who buys tubes as a getter.
 
RE: Tube or not Tube: That is the Question  
by N8IK on March 10, 2008 Mail this to a friend!
Gil - that's funny!!
 
Tube or not Tube: That is the Question  
by VE3BZX on March 10, 2008 Mail this to a friend!
A very nice article,i enjoyed it very much.I also enjoy using my older tube radios.I too have a tube collection and have always enjoyed working with vacuum tubes.
 
RE: Tube or not Tube: That is the Question  
by KL7AJ on March 10, 2008 Mail this to a friend!
ONAIR:

You are of course correct...I have a priceless collection myself! I was describing technical value, not monetary. :) But I shall not that in my next revision.

Eric
 
Tube or not Tube: That is the Question  
by TUBEGUY on March 10, 2008 Mail this to a friend!
Nice article! Where would electronics be today without them?
 
RE: Tube or not Tube: That is the Question  
by KL7AJ on March 10, 2008 Mail this to a friend!
I've been a getter for a long time. In fact, I've been accused of living in a vacuum. :)
 
RE: Tube or not Tube: That is the Question  
by KB7AIL on March 10, 2008 Mail this to a friend!
I got into radio just at the end of tha 'all tube' period. I just loved the glow of tubes when I was a kid.

When I was 7, I had a sickness and had to stay in bed most hours of the day and night. My father put the big family radio in my bedroom for me to listen to when I wanted to. It wasn't a fancy or rare model- I think it was a Silvertone and had a record player in it, too. I loved to look at the tubes glow through the back panel...

I guess when I was about ten, I got a one-tube radio kit with an "A" cell and a "B" cell. 2000 ohm magnetic headphones. I left it on all night once which caused the end of the batteries. "B" cells were very expensive and a 25-cent allowance doesn't go far. So that was the end of that.

I got my ham ticket in 87 so had kind of passed out of the tube era by that point but my friend, Tom (AA7VT) bought one of the last HW-101 kits available in our area and put it together. I have a Kenwood 520 which is 'kind of' a tube rig. It would be nice to be able to buy a tube kit to build something useful even if it was way too expensive for what I was getting....

Nice article. Thanks.
 
Tube or not Tube: That is the Question  
by K5BZH on March 10, 2008 Mail this to a friend!
Nice piece again Eric. Have to comment that although it is limited, my 4CX15000A makes a pretty good doorstop.
 
RE: Tube or not Tube: That is the Question  
by KL7AJ on March 10, 2008 Mail this to a friend!
ZH:
You'd exceed the legal input power just lighting the filament on the puppy! :)

Twas a great tube....used them in out FM broadcast transmitter. Only needed about 30 watts of drive to get a full 25 KW out of the thing. :)

eric
 
RE: Tube or not Tube: That is the Question  
by AB3CX on March 10, 2008 Mail this to a friend!
Too many hams are living off the grid...
 
RE: Tube or not Tube: That is the Question  
by N6AJR on March 10, 2008 Mail this to a friend!
tube-u-lar, dude
 
RE: Tube or not Tube: That is the Question  
by WB2WIK on March 10, 2008 Mail this to a friend!
Once, a long time ago when there were so few tube types they only needed a single letter for a part number,a very short ham (we might call him a "hamlet") was looking for an "E" type tube.

He had several that looked similar, and the choice was difficult.

He used to ponder, "Tube E, or not Tube E?"

People overheard this and slipped a note to a famous story writer. The rest is history.

WB2WIK/6
 
RE: Tube or not Tube: That is the Question  
by G3LBS on March 10, 2008 Mail this to a friend!
In England the E-types are Jaguars
 
RE: Tube or not Tube: That is the Question  
by WB2WIK on March 10, 2008 Mail this to a friend!
>RE: Tube or not Tube: That is the Question Reply
by G3LBS on March 10, 2008 Mail this to a friend!
In England the E-types are Jaguars<

::Or they used to be. I had a '62 E-type and I miss it. Are they bringing this back? I've heard rumors...


 
RE: Tube or not Tube: Too Much On Your Plate?  
by K4JSR on March 10, 2008 Mail this to a friend!
Eric, Now we've gone too far. Tom sez, "tube-u-lar, dude' and Steve says, Tube E or not Tube E?"

It looks like your nice article on Empty State is getting some FLEMING E-mails! Is there no way to suppress them? You know, CAP them off??

I was out camping one night. I was gleefully boiling off some free electrons on the camp fire when suddenly I had a secondary emmission!! It was quite an experience! Triode, You'll like it!! Goes great with a plate of PENTODE beans.

I know that in Alaska all of your ionics have to wear thermals this time of year. Do you think that would
effect Edison?

In the old days plate caps were real studs. They were made from Tube-A-Fours.

Well, I'll back out now and give others a chance to give you some TUBE socks! Don't step into any grid leaks. And beware of the Cathode Followers lurking about!

73, Cal K4JSR.

PS. Keep up the great work!
 
RE: Tube or not Tube: Too Much On Your Plate?  
by WI7B on March 10, 2008 Mail this to a friend!

Tubes are great. They take ALOT of abuse in real life from hams, and keep on ticking.

One thing not covered in this fine article is the role of "gettering". That little Ti sublimation pump inserted in every good tube is its real saving grace over time.

One could write a tome to the Ti "getter".

73,

---* Ken
 
Tube or not Tube: That is the Question  
by WB4ILP on March 10, 2008 Mail this to a friend!
Great, informative article and an interesting and entertaining writing style. Tubes will always be a part of my amateur radio "experience". I ran some neat old tube stuff back in "the day". Tubes have a mystery, an intrigue and a presence, all their own. When I was very young, I would put my grandad's "All American Five" by the bed and listen all night to the AM stations fading in and out, with the glow of the tubes out the back of the set, and the smell of those hot tubes filling the air. This was one of my earliest radio experiences and is a vivid memory even now. Looking at the electric halo as I listened to those far away voices; a warm, ethereal experience.
Jim
 
Tube or not Tube: That is the Question  
by VK5FDAV on March 11, 2008 Mail this to a friend!
I thought an "electron tube" was a TV tube or CRT. I have never heard of Valves or vacuum tubes being refered to as electron tubes.
 
RE: Tube or not Tube: That is the Question  
by G3LBS on March 11, 2008 Mail this to a friend!
I know I am giving some bright ideas to the author here, but any ham worth his salt will not be satisfied with heater glow. I once fired up (almost literally) a 100TH triode and was pleased to find the anode (plate) glow was cherry red at specified ratings. Occasionally there are 100TH's maybe 250TH's for sale on eBay.
 
Tube or not Tube: That is the Question  
by WA6BOB on March 11, 2008 Mail this to a friend!
Check this video out on YouTube.com about the making of a TUBE.

I also continue to use tube radios in entertainment, SWL, and amateur fields.

http://www.youtube.com/watch?v=8_eLO0exato

73, John (Bob) WA6BOB
www.wa6bob.com
 
RE: Tube or not Tube: That is the Question  
by KL7AJ on March 11, 2008 Mail this to a friend!
LBS:

The plate of an 833 glows even better. :)
 
RE: Tube or not Tube: That is the Question  
by KL7AJ on March 11, 2008 Mail this to a friend!
DAV:

Arrrgh! You Australians always have to be difficult...HI.

Well, there are tubes that are electron tubes that are not vacuum tubes, such as regulator tubes, thyratrons, ballasts, mercury vapor rectifiers and such. It would be improper to call these fellers vacuum tubes, and yet electrons are the main players inside them. If we just called them tubes, they could be anything from bicycle inner tubes to Fallopian tubes, both of which have limited application in radio.

Of course, we could settle the whole issure and call the whole lot Thermionic Devices, and be done with it.

No...we couldn't do that either, because that would leave out cold cathode tubes! My head is about to implode!

eric
 
RE: Tube or not Tube: That is the Question  
by N4KC on March 11, 2008 Mail this to a friend!
Careful with the fallopian tube reference, Eric! When I was in broadcasting, we had a lady who lived not far from our 50KW AM station who complained to the FCC, saying our signal had damaged her ovaries.

Luckily, the Commission never acted on the complaint, or our chief engineer might have taken "tube tester" to a whole new meaning.

Don N4KC
www.n4kc.com
www.n4kc.blogspot.com
 
RE: Tube or not Tube: That is the Question  
by W8JI on March 11, 2008 Mail this to a friend!
Eric,

I think we have to be a little more careful with the analogies used. Some of this, if it is intended to be a book, needs rewritten. It is unfortunately wrong.

The plate resistance of the tube is not responsible at all for the dissipation in the tube. It is a dynamic characteristic representing an imaginary resistance caused by a SMALL change in anode voltage not quite produucing the expected change in anode current.

It looks like plate resistance has been confused with the varying conduction of the tube as grid bias is changed, or the resistance of the anode to cathode path at a fixed anode voltage. It is this resistance that allows the tube to amplify,and is responsible for dissipation.


In other words plate resistance is determined by very slightly perturbing anode voltage with all other voltages held constant, and observing the delta in anode current. If it was a pure resistance the two would track according to Ohm's law. The tube is a little "tight" or "loose" on current flow and doesn't quite follow what a pure resistance would do as anode voltage is slightly perturbed. The current can and will change differently than expected for a small change in anode voltage as all other parameters are held constant.

This has NOTHING to do with dissipation. Anode dissipation is related to the kenitic energy of electrons striking the anode and the number of electrons, and tracks with anode to cathode voltage and anode current (ignoring secondary emission from other elements in the tube).

In other words if we had a tube with 1000 volts on the anode and one ampere of current, it would dissipate 1000 watts in the anode. The effective resistance of the path from anode to cathode would be 1000 ohms. This is NOT the plate resistance.

The plate resistance would be determined by measuring the anode current as we perturbed the anode voltage slightly. Say we change the anode from 1000 volts to 990 volts with no other changes. The anode current might change to .98 amperes for that change instead of the expected .99 amperes for a pure resistance.

The plate resistance would be dEb over dIb, or 10/.02, or 500 ohms. It can be millions of ohms for a multigrid tube, and very low resistance for a triode at low voltage. Clearly it has nothing to do with heat.

The heat in both cases would be the anode voltage times anode current at any instant of time. To determine the dissipation with a time-varying signal we would have to integrate the dissipation at many points to find the time-averaged dissipation. We can typically consider that Pin-Po in an amplifier, although integrating the dissipation at many points in the cycle will give a more accurate answer.

Also it is incorrect to say the grid only reduces electron flow. That's just wrong. The grid accelerates (when positive) or slows (when negative) electron flow. It does this through the effects of the electrostatic field between the grid wires. It is very common to run a grid positive with respect to the cathode. The end result of this is the grid or grids change the effective cathode to anode path resistance.

These were just two points. While the basic overview is a good effort many areas do not accurately describe the effects or parameters being discussed. It needs work.

We can't use trees and pebbles to describe pushing and pulling without actual contact or transfer of energy. Also plate resistance has nothing to do with heat.

73 Tom





 
RE: Tube or not Tube: That is the Question  
by KL7AJ on March 11, 2008 Mail this to a friend!
Hi Tom:

As always, I always value your input, and the invitation for you to contribute to the Opus still stands. :)

I won't argue with your definition of plate resistance...it is the accepted one. However, can we agree that the dissipation of the tube contributes to the overall EFFECTIVE resistance of a tube, and can be represented with a resistor in series with the plate resistance? (We could probably go into the work function, but that's probably more than my "audience" needs to know). Also, the normal definition of plate resistance doesn't account for the forward voltage drop of a diode.

As far as acceleration goes...I didn't mean to imply that it didn't happen....it most certainly does, as my log-rolling example shows. (I intentionally avoided classes other than A, where grid current might flow). I merely want to show that acceleration in an of itself is not the cause of amplfication. To oversimplify things a bit....
In the case of a single electron...it's really meaningless to talk about its velocity inside the tube. Amplification takes place when we control the NUMBERS of electrons moving...which may be RELATED to velocity, but not the bottom line. We can't ignore the statistical nature of this. Agreed?

Going back to plate resistance being imaginary. I think this can be entirely attributed to the transit time effects. If the transit time were zero, the plate resistance would be real. Am I wrong on this?

Again, your comments always welcome.

Eric

 
TRON  
by N2EY on March 11, 2008 Mail this to a friend!
How many of these can you identify?

Thyratron
Klystron
Megatron
Magnetron
Dekatron
Ignitron
Rectigon
Pliotron
Kenotron
Rhumbatron
Emitron
Coratron
Dynatron
Transitron

73 de Jim, N2EY
 
RE: TRON  
by KL7AJ on March 11, 2008 Mail this to a friend!
I can positively identify them all as trons!
 
RE: TRON  
by KL7AJ on March 11, 2008 Mail this to a friend!
How about the Phantastron (6AS7) a five-grid frequency divider. :)

eric
 
RE: TRON  
by KL7AJ on March 11, 2008 Mail this to a friend!
Oops. Make that the 6AS6. :)

gettin old here. ^_^
 
RE: Tube or not Tube: That is the Question  
by K6LHA on March 11, 2008 Mail this to a friend!
KL7AJ commented on March 11, 2008:

"LBS: The plate of an 833 glows even better. :)"

It should NOT 'glow' any more than a barely discernable red - if properly tuned AND neutralized.

I did my first tune-up on HF in February 1953 at 1 KW output of a BC-339 pre-WWII design transmitter. Neutralization as part of tune-up/QSY is IMPORTANT...as with any triode power amplifier.

At my assignment in the Army, some dude on another shift QSYed a BC-339 and didn't check neutralization. The transmitter took off on its own, plates glowing HOT enough to melt the glass envelope on either side of the plate. Outside air pressure made little inverted cones in the glass until it got too thin. As a result the HV power supply pooped out and had to be repaired by the depot (the one-ton HV transformer had to be replaced). The Officer In Charge had someone make a little stand holding the 'pushed-in' 833 with a sign warning dire consequences to the next dude who did that. It stayed atop the operating console for a few months until everyone got the picture.

Having 'plates glow red' makes as much sense as thinking a car motor is 'powerful' because it makes lots of noise out the exhaust pipe.

73 and keep cool, Len AF6AY
 
RE: TRON  
by K6LHA on March 11, 2008 Mail this to a friend!
N2EY tried to look very experienced on March 11, 2008:

"How many of these can you identify?"

How many in that list have you ACTUALLY used?

"Thyratron"

No problem...standard HV, high-current rectifier in the 1950s through 1960s, has been used quite a bit in INDUSTRIAL electronics (probably more than with any HF transmitters). It was also available as a tetrode in a 7-pin miniature glass envelope in a TTY time-division multiplexer designed for the USN in the 1950s.
That one collapsed four 60 WPM TTY circuits into one circuit (running around 300 Baud give or take), the tetrode thyratron an approximate equivalent of a two-triode flip-flop.

"Klystron"

Very standard local oscillator in radar sets of 1940s through 1970s, tuned plenty of them. Not very frequency mobile although some were specifically designed for that.

"Megatron"

Saw one in a movie house...it battled Godzilla, didn't it?

"Magnetron"

Absolute standard transmitter 'tube' in radar sets of the 1940s through the 1980s. For a DIODE it made a unique oscillator having fantastically-high peak power. The biggest use today is in the ubiquitous kitchen appliance known simply as a 'microwave.'

"Dekatron"

Cute-looking decade counter used in VERY early frequency counters of the 1940s to early 1950s. Not speedy, it might do 100 KHz rates if designed properly. It was more novelty than anything, watching the little glowing dot jump around in a clockwise direction while counting. It was on par with the 'thermometer' display (vertical neon bulbs) used in the first HP 524 frequency counters. Both were tiring to USE.

"Ignitron, Rectigon, Pliotron, Kenotron"

Why should anyone care?

"Rhumbatron"

Very special type designed specifically for Frequency Modulation, used mostly in FM BC transmittes. It was the cheap way to go instead of using Phase Modulation at lower frequency and multiplying via doublers, triplers. Most were a pain in the butt. At WREX-TV the aural transmitter used one and had to be checked twice a shift to make sure the carrier remained within broadcast specification.

"Emitron, Coratron, Dynatron"

Why are those 'important' for anyone to know NOW?

"Transitron"

There was one very-fast rise and fall-time pulse generator made in the early 1960s in the Los Angeles area. It used special tubes that were sometimes called 'transitrons' in the multis used for pulse width, pulse delay, and output stages. Beat the heck out of most vacuum tube circuits for very fast rise, fall times but got aced out by the evolving semiconductor circuits. A few were around in electronics industry test equipment inventory in the 1960s but were eventually dumped. Little application to amateur radio at any time, HF through microwaves. [but you will argue that point vociferously, no doubt]

Most THYRATRONS are gaseous types that don't have a hard vacuum. Tsk, tsk, you should have CORRECTED Eric on that! They are pretty to look at but so are LEDs...and LEDs come in several colors, not just blue.

Len, AF6AY
 
RE: Tube or not Tube: That is the Question  
by KL7AJ on March 11, 2008 Mail this to a friend!
AY:

Not so....many A.M. broadcast transmitters ran with the tubes red....even says so in the factory manuals! The 833 was famous for its lovely cherry glow...and the fact that it could operate like this for decades.

eric
 
Tube or not Tube: That is the Question  
by N4VNZ on March 11, 2008 Mail this to a friend!
Hams do it with big tubes!
 
RE: TRON  
by W4OKW on March 11, 2008 Mail this to a friend!
You forgot TimTron! WA1HLR
(-: 73 de Tom/W4OKW
 
RE: TRON  
by W4OKW on March 11, 2008 Mail this to a friend!
You forgot TimTron! WA1HLR
(-: 73 de Tom/W4OKW
 
More TRONs!  
by N2EY on March 11, 2008 Mail this to a friend!
"You forgot TimTron!"

You are correct, Sir! The one and only, well known in these parts, whether strapping or PW, whom I have heard many times.

--

Add Phasitron to the list, btw.

73 de Jim, N2EY
 
RE: More TRONs!  
by KA5JRX on March 11, 2008 Mail this to a friend!
Absolutely fasinating information. I have a tube transciever, it is my favorite radio. I wish I knew a lot more about the inner works of the tube. Great comments also. Thanks.
 
Tube or not Tube: That is the Question  
by KB2DHG on March 11, 2008 Mail this to a friend!
THANK YOU for the effort and education...
Tubes have always interested me... NO wait, Electronics intrest me. To me it is simply magic!
This article has sparked (no pun intended) my intrest even more to learn about tubes and transistors. I want to understand it all...
I look forward to your next installment.
and to the mockers of this article... lighten up. we are all in this hobby for the fun and knowlege... what ever floats your boat is fine but appreciate where we were and are!
 
RE: Tube or not Tube: That is the Question  
by W8JI on March 11, 2008 Mail this to a friend!
I won't argue with your definition of plate resistance...it is the accepted one. However, can we agree that the dissipation of the tube contributes to the overall EFFECTIVE resistance of a tube, and can be represented with a resistor in series with the plate resistance?>>

No. We can't agree. :-)

Plate resistance has nothing to do with the anode to cathode path resistance or heating.

Consider a tube that follows ohm's law as the anode voltage is perturbed. We have a low mu triode steady state anode voltage of 1000 and current of 1 amp. Now we lower the voltage to 990 and the anode current is .99A. We have 10/.01 or 1000 ohms. The tube would be dissipating 1000 watts.

Now we have a pentode and change the anode voltage, and the current barely changes. We have 1/.999999 for current change for the same 10 volts anode delta. Now we have 10/.000001 or 10 million ohms plate resistance, but dissipation is still 1000 watts.

Plate resistance really just defines how constant the current is as anode voltage is changed with all other parameters the same.

Dissipation is always related entirely to the kenetic energy of the electrons and the quantity of electrons, so it is anode to cathode voltage times current (neglecting other small secondary emission or other sources of electrons).

If we had a simple waveform we could integrate the dissipation at enough points in time to calculate the long term dissipation over an entire cycle, or use a modified Fourier analysis to look at complex waveforms.

<< Also, the normal definition of plate resistance doesn't account for the forward voltage drop of a diode.>>

That's still heat. If the diode drops 100 volts at 1 amp, the heating is 100 watts. I once talked to a fellow who had a model trolly car running from 12V car batteries and the way he controlled speed was with a bunch of gian diodes. He claimed the diode drop reduced voltage without heat. Wrong.

<<As far as acceleration goes...I didn't mean to imply that it didn't happen....it most certainly does, as my log-rolling example shows. (I intentionally avoided classes other than A, where grid current might flow). I merely want to show that acceleration in an of itself is not the cause of amplfication. To oversimplify things a bit....
In the case of a single electron...it's really meaningless to talk about its velocity inside the tube. Amplification takes place when we control the NUMBERS of electrons moving...which may be RELATED to velocity, but not the bottom line. We can't ignore the statistical nature of this. Agreed?>>

No. The control is by static fields, which apply force on charges without transferring energy. The log is a bad example. The ideal example would be something that restricts or encourages flow without physically applying or absorbing energy.

A better example would be a valve and water flow, or a gas and a valve, except then we have no way to show acceleration in the stream from a positive grid. By the way a grid can be positive and the tube be class A. Certain beam tubes have the electron stream missing the grid or accelerating anode.

Maybe a tilted earth that varies in tilt would be better.

<<Going back to plate resistance being imaginary. I think this can be entirely attributed to the transit time effects. If the transit time were zero, the plate resistance would be real. Am I wrong on this?>>

Yes.

Plate resistance has nothing to do with dissipation. It is a term that shows the constant current effects of the valve as anode voltage is change for fixed grid voltages.

They needed some term to describe how constant the current was if the anode voltage was varied. This tells us how "stiff" the resistance is, not what it is.

A pentode has very stiff current flow, which means the effective or real anode to cathode path resistance varies a great deal as anode voltage is changed. This is because the tube acts like constant current source. The grid voltages determine the anode current more than the anode voltage does.

For example a 6L6 in triode configuration has a plate resistance of 1700 ohms. Connect the same tube as a beam power tube and the plate resistance is 25,000 ohms at the same voltages.

That 25,000 ohms has NOTHING to do with heat or transit time. As a matter of fact they really didn't even need to call it ohms. They could have called it fishies. It's just that when it is voltage and current and represents an impedance (even if non-dissipative) we call it ohms. Ohms are often not anything to do with loss or heat. My feedline cable is 50 ohms. That's a ratio of inductance to capacitance along a unit length. Ohms can mean many things. It is often the ratio of the across vector to the thru vector, and not a resistance or reactance at all.

73 Tom


 
RE: Tube or not Tube: That is the Question  
by K6LHA on March 11, 2008 Mail this to a friend!
KL7AJ didn't like what I said and replied on March 11, 2008:

"AY:

Not so....many A.M. broadcast transmitters ran with the tubes red....even says so in the factory manuals! The 833 was famous for its lovely cherry glow...and the fact that it could operate like this for decades."

I based my observations on about 14 or 15 BC-339s that were running 24/7 at the Army's ADA transmitter site in '53 to '56. 1 KW RF output...some of them were exciters for a BC-340 10 KW power amplifier. HF all of them running CW with FSK TTY. When did YOU fire up a pair of 833s running 'cherry red?'

73, Len AF6AY
 
RE: Tube or not Tube: That is the Question  
by K6LHA on March 11, 2008 Mail this to a friend!
W8JI replied to Eric on 11 Mar 08 about 'plate resistance'

I'm not sure it's even worth arguing about. 'Plate resistance' is a small-signal value anyway, just like mu and transconductance.

To model the voltage gain of a small-signal tube stage, just have a constant-current generator connected across a 'plate resistance' in parallel with the load impedance. The constant-current generator current will be the transconductance (from tube specification) of the voltage across the grid input.

As an example, a 6BJ6 may have a plate resistance of about 250K and a plate load impedance magnitude of maybe 15K, all at a gm of about 3.3 mho. The 'plate resistance' will result in only a miniscule difference from the voltage gain obtained by just multiplying gm by the load impedance magnitude. All that while the plate and screen are drawing 12 mA from 100 to 250 VDC.
Just ain't no comparison of 'plate resistance' (the small-signal value) and power dissipated in the tube. <shrug>

Now, VERY FEW folks can get INTO vacuum tubes to change things, so why does everyone have to go into minutia about the innards of tubes? [very strange to me] But, there's now a few who will love to discuss the whichness of the what about semiconductor junctions AS IF they ever cut a mask or doped a wafer.
BTW, Hans Camenzind's book "Designing Analog Chips" is what I consider an EXCELLENT basic circuit text with lots of examples and good illustrations. [Hans designed the 555 Timer, one of the best-selling analog ICs of all time] But, TUBES seem to fascinate so many. I think it is from tubes' relative simplicity. Yet so many have gotten the wrong ideas about such simplicity and go on and on about some 'urban myths' of olden days. <shrug>

73, Len AF6AY
 
RE: Tube or not Tube: That is the Question  
by W4LGH on March 11, 2008 Mail this to a friend!
KL7AJ said..."Not so....many A.M. broadcast transmitters ran with the tubes red....even says so in the factory manuals! The 833 was famous for its lovely cherry glow...and the fact that it could operate like this for decades."

What you say here, may be true, but it doesn't make it correct. The station engineer either did NOT know how to load up the transmitter, or had a serious mis-match with his antenna! Could have also been a neutralization problem as well. The 833 was never made to run with the plates glowing red! Or any tube for that matter. With the plates glowing red, the amount of heat inside the tube would go way over spec, and usually resulted in breaking the seal around the tubes pins, none the less melting the glass bottle. Many FM station owners wouldn't cut their modulation by 10% to run an sca CARRIER either. They said they were cutting their power and range, which simply isn't true either.

Everyone thinks tubes are much more robust than solid-state equivs. This simply isn't true either as far as power output goes. They can be very fragle in that respect. They will hold up better to EMP's, static discharges, lightning etc.

Harris makes a 50KW solid-state Am broadcast transmitter and it is a much larger box than its tube equiv. ,just for the shear number of transistor banks need to generate that kind of power. The power supply is also much bigger, and the amount of heat generated by both solid-state and tube is NOT much different either. This same 50KW can be done very easy with just one tube, a much smaller physcial size and less loss hi-voltage power supply.

Tubes are great, especially in HI-POWER modes. Solid-State is great for low to medium power apps.

73 de W4LGH - Alan
http://www.w4lgh.com
 
RE: Tube or not Tube: That is the Question  
by KL7AJ on March 11, 2008 Mail this to a friend!
our old RCA BTA 250 standby transmitter used two 833s in push pull. I believe the BT1K also used them in the modulator. 833s were real workhorses in the broadcast business
 
RE: Tube or not Tube: That is the Question  
by KL7AJ on March 11, 2008 Mail this to a friend!
The following quote is directly from the RCA Transmitting tube manual.


The thermal emissivity of graphite depends on the treatment the surface has received. Compared with molybdenum anodes, graphite anodes operate at a visibly lower temperature for the same power dissipation. Some users of transmitting tubes find it convenient to judge the operating efficiency of a tube by observing the color temperature of the anode. With tungsten, molybdenum, and tantalum anodes this is easily possible, because at the normal operating temperature the anodes are distinctly cherry or orange-red in color. With graphite, however. practically no color can be seen in normal operation so that it is very difficult to judge visually how much energy is being dissipated by the anode.
 
RE: Tube or not Tube: That is the Question  
by W8JI on March 11, 2008 Mail this to a friend!
Alan,

You are incorrect when you say tubes were never designed to be operated with the anode red. As a matter of fact MANY tubes will fail if operated for an extended period without the anode heated red.

The molly anode 3-500Z or 4-400A are just two examples. There are hundreds other that will fail prematurely if not operated with anode color.

This is because some tubes coat the gettering material on the anode. Zirconium gettering material normally coated on anodes has to be heated to various color to remove gasses of different types. If you never heat the gettering materials on the anode to the proper temperature they will never degass the tube, and if a tube with large seal area in a glass envelope is not gettered periodically it will fail prematurely. This is especially true if the tube is exposed to moisture which reacts with the metal to glass bond and increases seal leakage.

The worse way to operate a 3-500Z, 4-125A, 4-400A, 4-1000A, 3-1000Z, and even an 833A is to never heat the anode to the point where the getter is activated. The getter Zirconium, common used in high power tubes (it gives the anode that gray powder look), has to be heated to a red color to activate.

RCA once had a problem with short tube life in the driver of a AM BC transmitter. The problem was they used a 4-400A and ran it so light the anode never heated. The solution was to use a lower dissipation tube of the same family and allow the anode to glow orange.

While not all glass power grid tubes use Zirconium, most of them do. Running them cold will seriously shorten tube life.

73 Tom
 
RE: Tube or not Tube: That is the Question  
by KL7AJ on March 12, 2008 Mail this to a friend!
JI:

Say Tom. Are you still considering coming to Alaska? The Alaska Hamvention (the first all Alaska event in 30 years) is going to be in Anchorage starting August 1. We plan on giving Dayton a run for their money. Well, maybe not...but it's going to be the biggest event up here in a long time. You'd be a most sought after speaker. I think they're still filling out their full agenda. But August is coming sooner than ya think!

73,

eric
 
RE: Tube or not Tube: That is the Question  
by N2EY on March 12, 2008 Mail this to a friend!
There's an easy way to check if tube anodes should show color: check the manual!

RCA Transmitting Tube manuals list whether or not the tube anode should or should not show color at maximum rated dissipation (ICAS or CCS). They use the terms "shows no color" "cherry red color" and "orange-red color".

TT-3 and TT-5 can be downloaded free from various sites. Google is your friend.

Of course if a tube is rated to run at cherry-red color and it's pushed to orange-red, bad things may happen. Or if it's supposed to have forced-air cooling and the forced-air is off or clogged...

Some tubes were made with different kinds of anodes, which has an effect on the expected color. Most of the 813s and 808s I have seen had graphite anodes, and should never be run showing any color at all, but I have seen one or two with metal anodes.

73 de Jim, N2EY
 
RE: Tube or not Tube: That is the Question  
by W8JI on March 12, 2008 Mail this to a friend!
Graphite anodes don't preclude color, but they limit it to a red color. Moly anode tubes can get orange or brighter.

Of course it varies with the tube, but every Eimac glass tube with a lighter gray color anode has zirconium and MUST be operated with some color or the tube will not degass.

It's a fallacy that running all tubes easier increases life, or that color is bad. The important point is life of some tubes is greatly reduced when the anode does NOT show color. For example Eimac 3-400Z, 3-500Z, 4-400A, 4-65, 4-125, 4-1000A, 3-1000Z, and so on have reduced life when operated without color.

73 Tom

 
Plate Color Facts  
by N2EY on March 12, 2008 Mail this to a friend!
From RCA Transmitting Tube Manual TT-5

Types 203, 805, 838: "Plate shows no color when the tube is operated at maximum CCS ratings"

Types 802, 804, 807, 813: "Plate shows no color when the tube is operated at maximum CCS or ICAS ratings"

Types 811A, 812A, 828: "Plate shows no color when the tube is operated at maximum CCS ratings, and shows a barely-perceptible red color when the tube is operated at maximum ICAS ratings"

Types 204A, 803: "Plate shows a barely-perceptible red color when the tube is operated at maximum CCS ratings"

Type 810: "Plate shows a barely perceptible red color when the tube is operated at maximum CCS ratings and shows a cherry-red color when the tube is operated at maximum ICAS ratings"

Types 4E27A/5-125B, 808: "Plate shows a cherry-red color when the tube is operated at maximum CCS ratings"

Types 806: "Plate shows cherry-red color when the tube is operated at maximum CCS ratings and orange-red color when the tube is operated at maximum ICAS ratings"

Types 4-65A, 4-125A/4D21, 4-250A/5D22, 4-1000A, 4E27/8001, 826, 834: "Plate shows orange-red color when the tube is operated at maximum CCS ratings"

And the much discussed type:

Type 833A: "Plate shows orange-red color when the tube is operated at maximum CCS or ICAS ratings"

73 de Jim, N2EY
 
RE: Tube or not Tube: That is the Question  
by K6LHA on March 12, 2008 Mail this to a friend!
KL7AJ quoted on 11 Mar 08:

"The following quote is directly from the RCA Transmitting tube manual."

"The thermal emissivity of graphite depends on the treatment the surface has received. Compared with molybdenum anodes, graphite anodes operate at a visibly lower temperature for the same power dissipation. Some users of transmitting tubes find it convenient to judge the operating efficiency of a tube by observing the color temperature of the anode. With tungsten, molybdenum, and tantalum anodes this is easily possible, because at the normal operating temperature the anodes are distinctly cherry or orange-red in color. With graphite, however. practically no color can be seen in normal operation so that it is very difficult to judge visually how much energy is being dissipated by the anode."

1. An IR optical thermometer can give a reasonable accuracy on plate temperature.

2. IR optical thermometry was probably not available at the time the RCA Transmitting
tube manual was written.

3. RF current meters were around in the early 1930s so the RF output power could be rather accurately measured, both forward and reverse powers.

4. DC power input to a power amplifier was accurately measurable in the 1920s.

5. Subtracting RF power output from DC power input should yield the power lost IN the tube (where else is all that wasted power going to go?).

6. I don't know what color an 833's plate is when it heats enough to soften the glass of its envelope...and I don't care to be around one when it happens...I just saw the aftermath of what DID happen to ONE transmitter using 833s. As I recall, the other 833 broke in several pieces. I don't recall any of us checking that 833 as to whether it had 'graphite coated anodes' much less the 'graphite treatment.' All I remember is that little display on the central operating console as well as having to help clean up the insides of the power amplifier section...and being one of several who pipe-rollered out the HV plate transformer for depot pickup (four guys moving about - maybe - a half-ton of transformer). That huge transformer was UNDER rated and could take a lot. It just didn't take it this one instance.

7. I don't recall anyone remarking on the COLOR or the LIGHT through that little viewport in a BC-339. That transmitter DID emit smoke and some nasty noises from within and that is how it was noticed quickly. A spare BC-339 was fired up quickly and the circuit back in operation carrying traffic within 15 minutes according to the ops log (visible the next day). Note: That required a quick check with the other station since that spare's antenna wasn't quite for that azimuth, therefore no traffic could be carried until the circuit was assured.

8. I'm not going to argue against the RCA Transmitting Tube Manual...not even if I worked for another RCA Division for 8 years. All I know is what CAN happen when things inside tubes get TOO hot. Operating 24/7 means conservative ratings have to be observed at all times to 'get the message through.'

73, Len AF6AY
 
RE: Tube or not Tube: That is the Question  
by K6LHA on March 12, 2008 Mail this to a friend!
N2EY posted some ambiguous comments on 12 Mar 08 such as:

"There's an easy way to check if tube anodes should show color: check the manual!"

...yawn. You could have answered with just 'RTFM.'

"RCA Transmitting Tube manuals list whether or not the tube anode should or should not show color at maximum rated dissipation (ICAS or CCS). They use the terms "shows no color" "cherry red color" and "orange-red color"."

So, what kind of color did YOURS show when operating near a full gallon?

"TT-3 and TT-5 can be downloaded free from various sites. Google is your friend."

So, you've given up on the phrase 'try it, you'll like it?'

How many more cute sayings have you stored away (all written by others)?

"Of course if a tube is rated to run at cherry-red color and it's pushed to orange-red, bad things may happen. Or if it's supposed to have forced-air cooling and the forced-air is off or clogged..."

As an old saying goes, 'if we had some ham we could have ham and eggs if we had some eggs.'

You've never run any with forced (air or liquid) cooling? Helped fix a BC-340 power amplifier once. It was water cooled, heat exchangers sitting just outside the big transmitter building. Apparently an air bubble developed and steam began accumulating. The mild steel tube jacket fractured and exploded. Heavy steel side panels kept all the pieces inside. No way to tell if those anodes were glowing or what, just read current on the meters. <shrug>

"Some tubes were made with different kinds of anodes, which has an effect on the expected color. Most of the 813s and 808s I have seen had graphite anodes, and should never be run showing any color at all, but I have seen one or two with metal anodes."

I'm sure you have. In some magazines, probably. Outside of that (Brit?) design of the 1970s you put together and keep talking about, what OTHER experience have you had with 'PA tubes of color?'

Nothing, absolutely nothing beats a PW-15 arc-over in its final PA compartment. That 15 KW HF transmitter had lots of glass windows (molded-in wire grid for safety) in that compartment. During the rare electrical storm in central Honshu, the rhombic it was working into might accumulate a charge and upset loading. Was a caution to every crew: Do NOT go near those 15s during an electrical storm. :-) Forced air cooling, jacket preventing viewing any color of the big, big anode connection. Didn't really matter. Outside of rare electrical storms, the PW-15 just kept on working 24/7 (as long as primary power was on).

Once an AN/TRC-1 VHF transmitter popped its HV fuse in the radio relay room. No one could pin down WHY it did, except examining the fuse itself (standard tubular type as required in the manual). The fuse, horizontally mounted, simply ARCED OVER inside its standard receptacle and kept the HV supply on. The HV supply transformer (potted in its case) heated up, deformed slightly, bent the chassis, sheared off two of its mounting bolts, and spewed black potting compound over about 1/3 of the under-chassis wiring. The radio relay man on each shift (four shifts) got the wonderful task of picking out potting compound for over a week. At the end of nearly two weeks, no one could figure out an easy way to reform the bent hard-aluminum chassis. Powers that be in higher echelons decided it should go to the Depot for 'further examination' and we got a replacement. TRC-1 (and -3, -4 sets) operated 70 to 90 MHz, used 829s in the final. We could open the top of the case and see parts of the 829 (mounted horizontally) but I've never seen one 'glow' at 50 W output. That was a most unusual situation since the Tracks (TRC) just kept on working and working and working.

In all the years since those first days I don't recall anyone WORRYING about 'final PA anode glow' other than DO NOT LET THEM GLOW. Period. If that was 'wrong' then I don't believe I was 'wrong' to write that. (you WILL comment on my 'wrongness' since you always manage to do that). In all the BC transmitters I've been around those that did glow (so that anyone could see them) did so from the incandescent filaments (more power demand than receiving tubes). I don't recall any klystron power amps (for UHF TV) that had 'anode glow' nor the more standard PAs of VHF TV. Don't even remember the tube type of the finals in the WBEL, WRRR, or WMCW AM BC transmitters...but it didn't matter much, did it? Those were all designed to just work and work and work and did so in my experience.

Ever WALK INTO a high power transmitter? I did on a friendly visit to KCOP-TV on Mt. Wilson out here a long time ago. [channel 13, same as where I worked at WREX-TV] Was a doorway at the corner junction of video and aural transmitter...the diplexer combiner was visible just overhead. KCOP had a lower-power Tx as a back-up along the far wall. Transmitting room was about the floor size of an average house.

I appreciate today's BC transmitters with hot-plug replaceable modules a LOT more...AND the solid-state PAs whose overall design is standardized to work with 50 Ohm loads. None of all that #$%^!! knob-twiddling of those old (beloved?) pi-networks...and they STILL meet the FCC standards for harmonic suppression of amateur transmitters. Let those old S-band magnetrons keep working inside those microwave ovens...those do a wonderful job...with food preparation. Let those TWTs (Travelling Wave Tubes) keep working in all those commsats, none of which are pressed into 'red hot' service and the 'repair bill' is too damn high to contemplate 'tube changing.' Each commsat is about 23K miles up (at shortest path) and that seems like 'DX' to me. :-)

Len, AF6AY
 
RE: Tube or not Tube: That is the Question  
by K6LHA on March 12, 2008 Mail this to a friend!
W8JI commented on 12 Mar 08:

"Alan, You are incorrect when you say tubes were never designed to be operated with the anode red. As a matter of fact MANY tubes will fail if operated for an extended period without the anode heated red."

"The molly anode 3-500Z or 4-400A are just two examples. There are hundreds other that will fail prematurely if not operated with anode color."

How about the final Tx stage in the BC-1000? :-)
...................

"The worse way to operate a 3-500Z, 4-125A, 4-400A, 4-1000A, 3-1000Z, and even an 833A is to never heat the anode to the point where the getter is activated. The getter Zirconium, common used in high power tubes (it gives the anode that gray powder look), has to be heated to a red color to activate."

"RCA once had a problem with short tube life in the driver of a AM BC transmitter. The problem was they used a 4-400A and ran it so light the anode never heated. The solution was to use a lower dissipation tube of the same family and allow the anode to glow orange."

"While not all glass power grid tubes use Zirconium, most of them do. Running them cold will seriously shorten tube life."

Will it? OK, most (but not all) of my experience was with high power HF transmitters a half century ago, right after only with a few high power MF transmitters. I have little recollection of any shortening of tube life in power amps by 'NOT' glowing the anodes...and that comes from seeing them ON for 24/7, interrupted only by QSYs. The 2C39s in GE microwave radio relay equipment sat in cavity assemblies and one couldn't see the anode surface from outside, only the external anode fins. That GE terminal had hot spare Rx and Tx so each one had twice the number of RF tubes all going. The spare Rx and Tx were sitting there with only the heaters on and, by what all seem to say, that would have been deleterious to tube life, yes? No sign of that during switchovers to spare terminals for routine maintenance checks. <shrug>

Since a half century ago, my experience has been with maggies, klystrons, and ceramic-metal (conventional) structure tubes. Whether or not their anodes glow is invisible to the user and I could care less if their getters haven't been got PROPERLY. The tubes either worked or didn't work and that was that. Few electronic labs could pull a really hard vacuum to get inside and operate on their innards, then reseal them. That's up to the tube MAKERS, not the users. RTFM as usual.

BTW, most magnetrons are really dual diodes. Klystrons have maybe a grid but a few other electrodes and a cavity (arrangements vary with small ones). Pencil triodes used in radiosondes were sealed inside their resonant cavities and couldn't be seen (a half-million a year used up in throw-away radiosondes '50 to '60s).

The only real problems I've encountered was with GE and 6442s (an oversized pencil triode in a ceramic metal envelope). That was with a distributor illegally remarking the 6442s as 'new' when they were really used. [those operated at the bottom of L-band in DME/TACAN] NOT a tube operating problem.

Speaking of 'seals,' why wouldn't the seal of ceramic-metal structures be as difficult as with glass-metal structure seals? I'm just idly curious and not wanting to do battle royal over 'who is right and who is wrong.' :-)

73, Len AF6AY
 
RE: TRON - The Answers  
by N2EY on March 12, 2008 Mail this to a friend!
Thyratron - Controlled hot-cathode rectifier, the hollow-state equivalent of an SCR/thyristor. Gas or mercury-vapor types.

Klystron - Velocity-modulated microwave vacuum tube.

Megatron - Another name for planar triodes known as lighthouse tubes (vacuum)

Magnetron - Microwave oscillator vacuum tube, uses magnetic field at right angles to electron path.

Dekatron - Decade counter tube, gas filled. Used in control systems.

Ignitron - Controlled rectifier version of mercury arc rectifier. Usually made in large sizes, water-cooled.

Rectigon - Commercial name for hot-cathode gas-filled rectifier also known as Tungar bulb.

Pliotron - Commercial name for early industrial vacuum triodes.

Kenotron - Commercial name for early vacuum rectifiers.

Rhumbatron - Early form of klystron.

Emitron - TV camera tube, mostly used in UK (which had regular broadcast TV in the late 1930s)

Coratron - Not a tube, but a device in laser printers and copiers to give an electrostatic charge.

Dynatron & Transitron - Not a tube but specialized oscillator circuits, using the negative resistance effect caused by secondary emission in tetrode and pentode vacuum tubes. The dynatron was popular in pre-WW2 amateur frequency meters.

Phasitron - Unique tube for FM broadcast transmitters.

TimTron - WA1HLR

73 de Jim, N2EY
 
RE: Plate Color Facts  
by K6LHA on March 12, 2008 Mail this to a friend!
N2EY, adamant on being the one always 'right' quoted the from RCA Transmitting Tube Manual TT-5 on 12 Mar 08:

"Types 203, 805, 838:"
"Types 802, 804, 807, 813:"
"Types 811A, 812A, 828:"
"Types 204A, 803:"
"Type 810:"
"Types 4E27A/5-125B, 808:"
"Types 806:"
"Types 4-65A, 4-125A/4D21, 4-250A/5D22, 4-1000A, 4E27/8001, 826, 834:"

"And the much discussed type:"

"Type 833A: "Plate shows orange-red color when the tube is operated at maximum CCS or ICAS ratings" "

OK, just WHEN and for HOW MUCH did YOU actually operate any of the above tubes at ANY power setting?

Anyone can quote from old documents about 'technical specifications.' But, is this a treatise on radio HISTORY or is it about actual working hardware at RF?

Have YOU ever, personally, fired up any 833s (any suffix letter)? Was there any anode glow or was the fire only in your eyes on finding a subject you throught you could argue about on screens (and try to win)?

Len, AF6AY
 
RE: Plate Color Facts  
by N2EY on March 12, 2008 Mail this to a friend!
Some more info:

Both the RCA and GE data sheets on the 833A say the plate is zirconium-coated.

73 de Jim, N2EY
 
RE: Plate Color Facts  
by W8JI on March 12, 2008 Mail this to a friend!
The problem with glass seals is not the glass, it is the Kovar alloy used to seal the glass to the metal stems coming through the glass. Kovar is very sensitive to moisture.

The problem is also the dissimilar expansion rates of glass and metal as temperatures cycle.

Ceramic tubes high power external anode tubes not only run cooler, they don't have the seal bonding problems since the ceramic is more easily metallized.

What I'm saying is an absolute fact. The quickest way to ruin a moly anode tube or a tube that has the gettering agent on the anode (some tubes have the gettering agent on the filament structure, but not the ones I mentioned) is to never heat the anode. Zirconium getters best at about 1000 degrees C. It doesn't getter at all at room temperature.

Someplace I have curves of gettering vs. temperature from some old engineering courses that covered high power vacuum tube design.

Cooler might be better in a 6146 that has the gettering of barium, magnesium, or strontium carbonates deposited on the glass..... or a ceramic external anode tube that has the gettering (like tantalum) on the filament structure for heat.

Not in those tubes with that powdery grey anode coating called zirconium. You want to shorten life on your 3-500's or 4-400's? Run them without color on the anode.

Some 833's are the same way.

Nearly all high power tubes require hot getters. Short of the external anode tubes, most use zirconium coated on the anode and the peak gettering temperature is 1000C. It can actually outgas at low temps.

RCA learned that lesson the hard way.

73 Tom
 
RE: Plate Color Facts  
by KL7AJ on March 12, 2008 Mail this to a friend!
Len:

For many years I ran herd on HIPAS Observatory's eight 150 KW transmitters. Until HAARP was fully operational last fall, HIPAS was the most powerful ionospheric heater facility in the United States. Each of our transmitters used a 4-1000Z for the driver, and they ALL ran cherry red. This is not just theory...this is how they worked...for decades. (The transmitters were built in the mid 60s for Platteville, and were moved up here in the 1982. Most of them were still running the original 4-1000Z's when I left).

By the way, the finals were 4cv100,000H3 vapor phase cooled tetrodes operated in grounded screen. They used no parasitic suppressors and were absolutely stable from 2-20 MHz (though we only ran them at 2.85 and 4.53 MHz).

Eric
 
RE: Plate Color Facts  
by W4LGH on March 12, 2008 Mail this to a friend!
First off everybody likes to be right. If you go back and read what was said, it talks about the "PLATE COLOR" @ the absolute MAXIMUM!! This does NOT mean you are suppose to run it this way, as you never run ANYTHING @ its absolute MAXIMUM for full time duty!!! NOTHING..NEVER! If you do you're in for a fall.

As for the "getter" material being coated on the plates of non-graphite tubes, you are correct, and they have a burn in time that you do run these tubes with the plates very hot to degase the tube. This us usually a 24 hr period. Once the plates glow, this material is burned off and the tube is degased. Continuous use running the tubes with this plate color will do it no good and will only shorten its life.

So though the manual may say they do this, it DOES say at it MAX rating. Go back and read it several more times until you get it. Read what it says, not what you want it to say.

I have 2 amps here that run a pair of 3-500z's. One amp is almost 40 years old, and I still running the ORIGINAL tubes in it and it usually runs about 1450watts out. The other amp over 25 years old and it too has the ORIGINAL 3-500z's in it. The difference in this amp is the plates run 3200volts at full keydown, and it will still loaf along @ 1800watts and I do NOT let the plates GLOW!! When I have made them GLOW by accident, the fans kick into HI-GEAR and it sounded like a vacuum cleaner running. Any station that I engineered, if the owner made them GLOW, he was replacing them a lot more often than he should have, and after several sets being changed out, they usually listened to me. Only doing the burn in period do you run these tubes with a glow, after that you are killing it.

You can run yours anyway you want, I am not buying them! But having 4 original 3-500z's that have been in service as long as mine have, kinda proves my point.

73 de W4LGH - Alan
http://www.w4lgh.com

 
RE: Plate Color Facts  
by N2EY on March 12, 2008 Mail this to a friend!
More from the RCA Transmitting Tube Manuals:

From the 833A specifications:

"Plate shows an orange-red color when operated at maximum CCS or ICAS ratings"

"Continuous Commercial Service (CCS) covers applications involving continuous tube operation in which maximum dependability and long tube life are the primary considerations"

So, according to the manufacturer's ratings and definition, the 833A (which has a zirconium-coated anode) can be run continuously under conditions where maximum dependability and long tube life are the primary considerations, and the plate shows an orange-red color in normal operation.

It should be remembered that there are 8760 hours in a year (8784 in a leap year), so if a tube lasts 20,000 hours, that works out to a little more than 2-1/4 years of continuous service.

But few amateur transmitters are in continuous service. (Busy repeaters come close, and there are amateur beacon stations). Even a very active amateur has to listen at least half the time if s/he is actually making QSOs. So even an active amateur might only be transmitting 10% of the time, and that same 20,000 hour tube would last more than 22 years.

73 de Jim, N2EY
 
RE: Plate Color Facts  
by K6LHA on March 12, 2008 Mail this to a friend!
N2EY continued to argue his very important postings on 12 Mar 08:

"More from the RCA Transmitting Tube Manuals:"

"From the 833A specifications:"
_________

"Plate shows an orange-red color when operated at maximum CCS or ICAS ratings"

"Continuous Commercial Service (CCS) covers applications involving continuous tube operation in which maximum dependability and long tube life are the primary considerations"
_________

"So, according to the manufacturer's ratings and definition, the 833A (which has a zirconium-coated anode) can be run continuously under conditions where maximum dependability and long tube life are the primary considerations, and the plate shows an orange-red color in normal operation."

"It should be remembered that there are 8760 hours in a year (8784 in a leap year), so if a tube lasts 20,000 hours, that works out to a little more than 2-1/4 years of continuous service."

Oh, my, I've been remiss in my youth...the Army wouldn't let me keep my zirconium-testing kit with me. And I plumb forgot to note whether any of the 833s in the BC-339s were the 833A or had none or some other suffix. Tsk, tsk, on me.

Army radio station ADA began full operation in late 1945...but I didn't see a station history from that time when I was assigned there by February 1953. At that time there were 12 to 13 BC-339s in service with 90 to 95% operation (down only for monthly maintenance which was minimal). In '53 ADA had three dozen HF transmitters. Most BC-339s had been built by Lewyt Vacuum Cleaner Company between 1944 and 1945 according to their nameplates. So, they had been in-service for well over 3 years when I left for the USA in 1956. The average 833 replacement was one a year for the whole station (if operated correctly, the lack-of-neutralizing blow-up was not a fault of normal running). Since each BC-339 had two in the finals that meant 24 to 26 big bottles total IN USE. Since those were ALREADY in use when I got there, all of them exceeded that magic 20K hours time period. The only 'color' anyone noticed through the little porthole window in the front was the FILAMENT, a yellow-orange color. As I recall, those 833s that were replaced suffered filament burn-out. We (anyone on the four operating teams) would have noticed the anodes at an orange-red color and notified the trick chief. For a few months after the '54 holiday year end period I was one of those trick chiefs (operating team leader). Trick chiefs also did a couple walk-arounds each shift to check for themselves to keep the crews alert.
...............
"But few amateur transmitters are in continuous service. (Busy repeaters come close, and there are amateur beacon stations). Even a very active amateur has to listen at least half the time if s/he is actually making QSOs. So even an active amateur might only be transmitting 10% of the time, and that same 20,000 hour tube would last more than 22 years. "
How many ham station transmitters (on HF) are there using 833s (any suffix) now? Please tell us from your vast experience with HF transmitters. A BC-339 needs a concrete floor and would probably collapse the usual residential wooden flooring. <shrug> Are those amateur beacon stations you mention running a full gallon RF output? [I don't think so]

What brand of zirconium-anode testing equipment have YOU got? Should I get one of those?

ADA original equipment in Tokyo lasted (maybe) until 1978, all operation of equipment was transferred from Army to USAF in 1963. The entire HF and microwave station was given to the Japanese in '78, ENTIRE. ADA was reactivated in 1963 at Fort Shafter, Hawaii, the new Hq for the US Army Pacific and retains that HQ call sign to this day. I'm proud to have been a part of that little-known - and hardly appreciated by hams - Army radio operation that stretched around the world. We kept getting the messages through. 24/7/365

Len, AF6AY [ex RCA Corporation, EASD, employee]
 
RE: Plate Color Facts  
by K6LHA on March 12, 2008 Mail this to a friend!
W4LGH wrote on 12 Mar 08:

"First off everybody likes to be right. If you go back and read what was said, it talks about the "PLATE COLOR" @ the absolute MAXIMUM!! This does NOT mean you are suppose to run it this way, as you never run ANYTHING @ its absolute MAXIMUM for full time duty!!! NOTHING..NEVER! If you do you're in for a fall."

Alan, I would only reply that your first sentence should read "everybody HAS to be right." Especially you-know-who. :-)

73, Len AF6AY
 
RE: Plate Color Facts  
by KL7IPV on March 12, 2008 Mail this to a friend!
I don't care what they others say, I enjoyed the review to refresh what I learned so many years ago. I am thinking also about attending the Hamfest as it seems it is becoming a "reunion" of the past officers and members of KL7AA. I did the program for the 1978 fest and it would be fun to attend another there.
73,
Frank
 
RE: Plate Color Facts  
by W8JI on March 13, 2008 Mail this to a friend!
My experience with tubes and color, besides working experience, is directly talking to tube design engineers at RCA and Eimac as part of the process of designing high power amplifiers. Engineers from varian Salt Lake would visit Prime Instuments and Heathkit several times a year to discuss new tube designs.

The folks at Salt Lake City (where large glass tubes were made) very clearly warned against operating tubes like the 3-500Z or 4-1000A below anode temperature that shows some red color.

So did RCA with its tubes that used the anode for gettering, a common method of gettering high power glass tubes.

Speculating by yourself otherwise as a guess or assumption doesn't trump or outweigh what tube designers actually recommend during the new equipment design process. They know their products a lot better than a fellow sitting at a desk reading a tube manual does.

73 Tom

 
RE: Plate Color Facts  
by N2EY on March 13, 2008 Mail this to a friend!
RCA Transmitting Tube Manual TT-5 (1962) describes the 833A as having a zirconium-coated plate. This got me wondering about its predecessor, the 833, so I got out TT-3 (1940).

The original 833 has a tantalum plate, with no mention of a coating. On page 91, the book says:

"The plate of the 833 shows an orange-red color at the maximum plate dissipation rating for each class of service".

So at full rated power, both the 833 and 833A would be expected to show color on the plate. RCA tubes, anyway.

73 de Jim, N2EY
 
RE: Plate Color Facts  
by K6LHA on March 13, 2008 Mail this to a friend!
N2EY continued to state his 'rightness' on March 13, 2008:

"RCA Transmitting Tube Manual TT-5 (1962) describes the 833A as having a zirconium-coated plate. This got me wondering about its predecessor, the 833, so I got out TT-3 (1940). The original 833 has a tantalum plate, with no mention of a coating. On page 91, the book says:

"The plate of the 833 shows an orange-red color at the maximum plate dissipation rating for each class of service".

So at full rated power, both the 833 and 833A would be expected to show color on the plate.

RCA tubes, anyway."

...so begins a very long, protracted exercise in (possibly) acquiescing to other's viewpoints. :-)

As Tom has tried to explain, ACTUAL WORK WITH high power RF amplifiers has a bit more precedence than 'just sitting at a desk reading a manual.'

Now, I don't even try to make myself out as an 'expert' on HF transmitter power amplifiers, but I DID cut my radio teeth (so to speak) on a BC-339 using a pair of 833s in its final and DID QSY them (as well as pull maintenance on them) for nearly two years after that beginning (in February 1953). Over a dozen of those at one station. Had I ever noticed any of those finals 'glowing their anodes' I definitely would have remembered it and stated it. There was no reason not to do so.

That pre-WWII design (of the '339) looked to be very conservative in its design, considered in retrospect. Just from the sheer bulk and weight of the HV transformer I would hazard a guess that it might have been pushed to 2 or 3 KW output, possibly 5 (?). We are talking HEAVY DUTY construction throughout on their insides.

I'll add this: On a Signal Corps okayed directive, ADA tried an AM version of the '339 using a Wilcox transmitter modulator that had become a spare after an upgrade of equipment had replaced the whole Wilcox set (including three separate HF transmitter drawers, the
ultimate in 'bandswitching'). That was to be used for the Far East Command Hq aircraft communications and could simultaneously send RTTY. The AN/GRC-26 mobile 400W HF station had simultaneous AM and FSK TTY capability in the field already. I helped SFC Don Ross on the interwiring and test of that combo. It worked okay and was on standby for a few months but tactical need changes for FEC Hq and growth of station ADA itself precluded keeping it around. The Wilcox AM modulator was also conservatively rated, a civilian design intended for civil airways service on over-ocean flights. Those Wilcox units didn't have much in
the way of windows for 'obsserving the color of anodes' unless one of the Tx drawers was slid out (designed to do that for alignment and test, didn't break the interlock so such sliding was very frowned upon).

I'll liken the 'glow that anode!' comments to be on par with the Detroit-iron era Horsepower Race which was far more a thrill for emotions than actual speed or 'performance' on roadways. It is rather useless for longevity, just as modern draggers and funny cars and
the like at drag strips are useless for ordinary transport beyond a few hundred yards. So WHAT if you can push the anode cherry enough to read comic books by...it might not last long enough to accumulate a hundred QSL collection...but it is good for sitting around and bragging about horsepower of your Tx...or making officious quotes from 'authoritative sources' and pretending to sound like a 'foremost authority.' :-[

It's come down to 'push,' Jimmy. Just what is YOUR experience in doing anything with HF power amplifiers above 100 W output? Give us your creds from hands-on experience...besides sitting and reading old handbooks written by professionals in the business of making and selling tubes. If you just want to remain confrontational and argumentative, go back to rec.radio.amateur.policy and have a ball there. You did that for a decade.

Len, AF6AY
 
RE: Plate Color Facts  
by N2EY on March 13, 2008 Mail this to a friend!
W8JI wrote: "Speculating by yourself otherwise as a guess or assumption doesn't trump or outweigh what tube designers actually recommend during the new equipment design process."

Agreed! Thanks to you and KL7AJ for the good solid info.

"They know their products a lot better than a fellow sitting at a desk reading a tube manual does."

I hope you weren't referring to me as the "fellow...reading a tube manual".

My reason for quoting from the RCA books was simply to point out that those books back up everything you've written here, and that the info is readily accessible for all who are willing to look for it.

73 es tnx agn de Jim, N2EY
 
RE: Plate Color Facts  
by KL7AJ on March 13, 2008 Mail this to a friend!
http://www.rossrevenge.co.uk/tx/five.htm

Actual 833 in operation
 
RE: Plate Color Facts  
by N2EY on March 13, 2008 Mail this to a friend!
Interesting article on getter materials:

http://www.thevalvepage.com/valvetek/getter/getter.htm

From the article:

"The optimum gettering temperature for tantalum appears to be in the neighborhood of 1,000 C....The maximum getter effect is secured, therefore, by dimensioning tantalum anodes so that during normal service the electrodes operate at red to yellow heat."

"While zirconium is effective as a getter from about 400 C on, it is most active at temperatures up to 1,600 C if used, for example, on molybdenum and carbon anodes."

A chart at the end of the article lists operating temperatures for various getter materials:

Tantalum (Ta): 700 to 1200 degrees C

Zirconium (Zr): 800 to 1600 degrees C

The 833 used a tanatalum plate while the 833A used a zirconium-coated plate.


73 de Jim, N2EY
 
RE: Plate Color Facts  
by K6LHA on March 13, 2008 Mail this to a friend!
KL7AJ posted on March 13, 2008:

"http://www.rossrevenge.co.uk/tx/five.htm"

"Actual 833 in operation"

Here's another:

http://sujan.hallikainen.org/BroadcastHistory/uploads/My3Years.pdf

Actual 833s in operation...plus a lot of other RF power tubes...all in three dozen HF transmitters.

73, Len AF6AY
 
RE: Plate Color Facts  
by N2EY on March 14, 2008 Mail this to a friend!
http://www.thevalvepage.com/valvetek/getter/getter.htm

article appeared in "Electronics" for October 1950.

Some pictures of 833s in action:

http://www.drspark.org/images/tube_fisrt_light.jpg

http://www.positive-feedback.com/Issue18/images/039-Wavac-833A.jpg

--

In the Eimac Application Notes about their tubes (aka "The Care and Feeding of Power Tetrodes") there is a warning not to run the tubes with light loading because there will be excessive electron bombardment of the glass, which can soften the envelope to the point of suck-in.

73 de Jim, N2EY
 
RE: Plate Color Facts  
by K6LHA on March 14, 2008 Mail this to a friend!
N2EY, unable to give up his 'correct everyone wrong' fetish, posted on 14 Mar 08:

"http://www.thevalvepage.com/valvetek/getter/getter.htm

"article appeared in "Electronics" for October 1950.

"Some pictures of 833s in action:

"http://www.drspark.org/images/tube_fisrt_light.jpg

"http://www.positive-feedback.com/Issue18/images/039-Wavac-833A.jpg

"In the Eimac Application Notes about their tubes (aka "The Care and Feeding of Power Tetrodes") there is a warning not to run the tubes with light loading because there will be excessive electron bombardment of the glass, which can soften the envelope to the point of suck-in."

'Suck-in?!?' So, if one runs the anodes red, the glass is 'strengthened' and isn't affected?!?

'Excessive bombardment of the GLASS?!?'

Something must be WRONG in your quote...if for no other reason than millions of low-power GLASS enclosed vacuum tubes used in millions of BC and TV receivers around the world.

Take a TV picture tube, the classic CRTs...the electron beam in older oscilloscopes goes DIRECTLY to the glass faceplate and the phosphor coating on the vacuum side. Are you now going to argue that the phosphor 'protects' the glass from electron bombardment so that the faceplate doesn't 'suck-in?' Color TV picture tubes are protected (somewhat) by the shadow mask (photolithographically etched for perforations) which is metal, but the beam is
accelerated by 22 to 24 KV, enough to cause mild X-Ray generation.

I've never heard of any 'suck-in' due to glowing anodes in any CRT...only physical damage from blunt forces (usually deliberate, such as in trashing old black-and-white TV CRTs before 'green' and 'recycling' became watchwords).

I've seen lots of power pentodes used as TV horizontal sweep output (and final electrode or 'ultor' acceleration potential supply) and NONE of them had any evidence of 'glass damage' or 'suck-in.'

The same with high-fidelity tube power amplifiers in home music systems using GLASS envelope tubes (up to 80 W AF out that I recall). While some of them (as in guitar amplifiers) 'sucked' as to fidelity and linearity, I've not heard of any that suffered envelope 'suck-in' due to anodes NOT glowing.

Now lets take INCANDESCENT LIGHTS. Most of those, including those of POWER (up to 300 W that I can recall seeing). NO ELECTRODES other than a filament. Total 'bombardment of the glass' and can't recall any conditions of 'suck-in.' Millions and millions of those made and in use...tungsten alloy filaments and some lights without interior coating, all in a hard vacuum.

Let's get to the bottom line: YOU don't want ANYTHING contrary to your personal beliefs so you keep up this supposed 'engineering facts by authorities' messaging in order to keep your personal beliefs supposedly valid. I doubt YOU have EVER fired up any vacuum tube RF power amplifier circuit above 100 W RF output in ANY radio service for anyone. You may have been an extra class radio amateur since your teen days but YOU have zilch experience in tuning up HIGH POWER HF transmitters. I got started in professional radio doing just that, at RF with 1 to 15 KW RF carrier power outputs, 55 years ago. Are we going to turn to
someone sitting at a desk reading OLD literature as an 'authority' or are we going to listen to some of us who have actually, manually tuned up vacuum tube RF POWER amplifiers?

I related a story - as an actual witness of the immediate aftermath - of a REAL LIFE glass 'suck-in' of a pair of 833s in a working HF transmitter. I'm not embellishing any of that nor retracting it. No need to. It happened and nothing YOU say will cancel that out. Now, if you insist (and you do seem to INSIST in all caps) that YOU are right and I am wrong, then you go and build a high power RF amplifier stage and run it under controlled conditions (preferrably
with witnesses who can think and observe for themselves) for 'glow' or 'no-glow' anode operation. Then you must carefully examine the glass envelope for 'suck-in' and report the same. YOU will probably NOT do that but try to act 'offended' about replies to your postings (a regular thing with you) and offer nothing of your own experience except ambiguous statements, embellished by the WORDS OF OTHERS WRITTEN LONG AGO.

'Suck-in?' Suck it up, Jimmy.

AF6AY

PS: Some more pictures of HF transmitters in communications, not broadcasting, circa 1963:

http://sujan.hallikainen.org/BroadcastHistory/uploads/AlphabetSoup.pdf
 
More Tube Pictures  
by N2EY on March 14, 2008 Mail this to a friend!
Glass tubes in action:

833:
http://www.drspark.org/images/tube_fisrt_light.jpg

http://www.positive-feedback.com/Issue18/images/039-Wavac-833A.jpg

http://www.w9amr.com/wb9eck/wb9eck3.jpg


304TL:
http://www.sonicflare.com/_news_oswaldsmill_images_jeffamp2.jpg

http://www.alumrocktech.com/images/small/20a.jpeg

http://www.arrl.org/tis/info/images/304TL.jpg


4-400A:
http://www.hawkins.pair.com/atcitynj/atcity14b.jpg

3-1000Z:
http://www.g4ftc.co.uk/amplifiers/rf104/rf104.jpg


866/866A:
http://www.arduman.com/aa/Resimler/slagle/tube.jpg

http://www.teresaudio.com/haven/verus/glow1.jpg


75TL:

http://www.positive-feedback.com/Issue5/images/5.Electron-Luv-75-TL.jpg

73 de Jim, N2EY
 
RE: More Tube Pictures  
by W4LGH on March 15, 2008 Mail this to a friend!
N2EY ole JIMMY continues to show examples he has found searching on Google. I guess Google has made a bunch of "Sudo Experts" over the past few years.

Oh well, I have to go run an HF net and try to keep my plates from running red.

73 de W4LGH - Alan
http://www.w4lgh.com

 
RE: More Tube Pictures  
by K6LHA on March 15, 2008 Mail this to a friend!
W4LGH remarked on March 15, 2008:

"N2EY ole JIMMY continues to show examples he has found searching on Google. I guess Google has made a bunch of "Sudo Experts" over the past few years."

Heh heh, Alan...the Name of His Game is To Prove Hisself Right in posting. Never mind his never having fired up anything of RF POWER, he HAS to be 'right.'

Nothing new in Jimmy's style of writing, but the photographs on those links are very pretty in a photogenic sense. So is an old Dusenberg touring car of the late 1920s-early 1930s (to old car afficionados). If it is OLD, it MUST be good...:-)
.....
"Oh well, I have to go run an HF net and try to keep my plates from running red."

No doubt Jimmy's ears are turning a bit red right now. :-)

73, Len AF6AY
 
RE: Plate Color Facts  
by K8MN on March 15, 2008 Mail this to a friend!
Alan wrote:

"First off everybody likes to be right. If you go back and read what was said, it talks about the "PLATE COLOR" @ the absolute MAXIMUM!! This does NOT mean you are suppose to run it this way, as you never run ANYTHING @ its absolute MAXIMUM for full time duty!!! NOTHING..NEVER! If you do you're in for a fall."

What was quoted were the terms, "at CCS Maximum or ICAS Maximum". Neither of these is maximum for the tube.
Tom W8JI has provided factual information. Jim N2EY has provided factual information. You can attempt debate, but the facts are still there.

and Len Anderson added:

"Alan, I would only reply that your first sentence should read "everybody HAS to be right." Especially you-know-who. :-) "

In this case, Len, it would appear that you are playing the part of "you-know-who". The fact is, you've gotten it wrong. Either you don't remember correctly your military experience or those tubes weren't being run anywhere near their CCS or ICAS maximum.

Dave K8MN
 
RE: Plate Color Facts  
by K8MN on March 15, 2008 Mail this to a friend!
Alan wrote:

"First off everybody likes to be right. If you go back and read what was said, it talks about the "PLATE COLOR" @ the absolute MAXIMUM!! This does NOT mean you are suppose to run it this way, as you never run ANYTHING @ its absolute MAXIMUM for full time duty!!! NOTHING..NEVER! If you do you're in for a fall."

What was quoted were the terms, "at CCS Maximum or ICAS Maximum". Neither of these is maximum for the tube.
Tom W8JI has provided factual information. Jim N2EY has provided factual information. You can attempt debate, but the facts are still there.

and Len Anderson added:

"Alan, I would only reply that your first sentence should read "everybody HAS to be right." Especially you-know-who. :-) "

In this case, Len, it would appear that you are playing the part of "you-know-who". The fact is, you've gotten it wrong. Either you don't remember correctly your military experience or those tubes weren't being run anywhere near their CCS or ICAS maximum.

Dave K8MN
 
RE: Plate Color Facts  
by K8MN on March 15, 2008 Mail this to a friend!
N2EY provided a number of url's showing vacuum tubes in operation. He added:

"In the Eimac Application Notes about their tubes (aka "The Care and Feeding of Power Tetrodes") there is a warning not to run the tubes with light loading because there will be excessive electron bombardment of the glass, which can soften the envelope to the point of suck-in."

to which Len Anderson replied:

"'Suck-in?!?' So, if one runs the anodes red, the glass is 'strengthened' and isn't affected?!?"

and

"'Excessive bombardment of the GLASS?!?'"

The well known Eimac note addressed what could happen if the tube/tubes were lightly loaded. The term "excessive bombardment of the glass" is used by Eimac.


Len:
"Something must be WRONG in your quote...if for no other reason than millions of low-power GLASS enclosed vacuum tubes used in millions of BC and TV receivers around the world."

Do you know of any user of broadcast receivers or television sets which had any option of adjusting the loading of a vacuum tube within those receivers?


Len:
"Take a TV picture tube, the classic CRTs...the electron beam in older oscilloscopes goes DIRECTLY to the glass faceplate and the phosphor coating on the vacuum side. Are you now going to argue that the phosphor 'protects' the glass from electron bombardment so that the faceplate doesn't 'suck-in?' Color TV picture tubes are protected (somewhat) by the shadow mask (photolithographically etched for perforations) which is metal, but the beam is
accelerated by 22 to 24 KV, enough to cause mild X-Ray generation."

Do you have any idea of how thick the glass on the face of the typical CRT might be, Len? Do you know what type glass is used?


Len:
"I've seen lots of power pentodes used as TV horizontal sweep output (and final electrode or 'ultor' acceleration potential supply) and NONE of them had any evidence of 'glass damage' or 'suck-in.'"

But that's one of the places one would typically find suck-in damage--in a horizontal output tube. Some manufacturers changed to Nonex glass to combat the problem.

Len:
"Now lets take INCANDESCENT LIGHTS. Most of those, including those of POWER (up to 300 W that I can recall seeing). NO ELECTRODES other than a filament. Total 'bombardment of the glass' and can't recall any conditions of 'suck-in.' Millions and millions of those made and in use...tungsten alloy filaments and some lights without interior coating, all in a hard vacuum."

Incandescent lamps are not vacuum tubes. They are not run at high potential and do not involve RF, but you can bank on the fact that those filaments are glowing--not red, but white hot. You'll never see a thing like suck-in on them. They're made of very brittle glass.

Len:
"Let's get to the bottom line: YOU don't want ANYTHING contrary to your personal beliefs so you keep up this supposed 'engineering facts by authorities' messaging in order to keep your personal beliefs supposedly valid."

His personal beliefs? The things Jim has stated are fairly widely known and he has submitted documentation to support his statements.

Len
"I doubt YOU have EVER fired up any vacuum tube RF power amplifier circuit above 100 W RF output in ANY radio service for anyone. You may have been an extra class radio amateur since your teen days but YOU have zilch experience in tuning up HIGH POWER HF transmitters."

Why would you state that you have doubts, then go on to say, "YOU have zilch experience in tuning up HIGH POWER RF transmitters"? From what you've presented here about your military experience of long ago, we might conclude that was the sum total of your high power RF experience--one type transmitter using one type of vacuum tube


Len:
"I got started in professional radio doing just that, at RF with 1 to 15 KW RF carrier power outputs, 55 years ago. Are we going to turn to
someone sitting at a desk reading OLD literature as an 'authority' or are we going to listen to some of us who have actually, manually tuned up vacuum tube RF POWER amplifiers?"

Jim has been a ham for over forty years. As I recall, you entered amateur radio a little over a year ago.
Your recent experience in high power RF appears to have been over a half century ago. None of the "OLD literature" on the matter seems to have been disproven and much of it is more up to date than your military radio experience. Why not outline your more recent experience with high power RF, Len. Do you own a high power, vacuum tube amateur radio amp which runs high power? What has been your experience?


Len:
"I related a story - as an actual witness of the immediate aftermath - of a REAL LIFE glass 'suck-in' of a pair of 833s in a working HF transmitter. I'm not embellishing any of that nor retracting it. No need to. It happened and nothing YOU say will cancel that out."

One of the 833's weaknesses is in the seals of the metal to glass points. What you experienced in the military may have been such a failure. It may not have been suck-in. In the suck-in, the glass actually begins to melt. It is visible as such.


Len:
"'Suck-in?' Suck it up, Jimmy."

Why was that necessary, Len? Try to behave in a civilized manner.

Dave K8MN
 
RE: Plate Color Facts  
by W4LGH on March 15, 2008 Mail this to a friend!
W8MN copied and then said..."Alan wrote:
"First off everybody likes to be right. If you go back and read what was said, it talks about the "PLATE COLOR" @ the absolute MAXIMUM!! This does NOT mean you are suppose to run it this way, as you never run ANYTHING @ its absolute MAXIMUM for full time duty!!! NOTHING..NEVER! If you do you're in for a fall."
W8MN comment..."What was quoted were the terms, "at CCS Maximum or ICAS Maximum". Neither of these is maximum for the tube. Tom W8JI has provided factual information. Jim N2EY has provided factual information. You can attempt debate, but the facts are still there."

and Len Anderson added:

"Alan, I would only reply that your first sentence should read "everybody HAS to be right." Especially you-know-who. :-) "

In this case, Len, it would appear that you are playing the part of "you-know-who". The fact is, you've gotten it wrong. Either you don't remember correctly your military experience or those tubes weren't being run anywhere near their CCS or ICAS maximum.
=================================================

Well here we go again with using was is published in the manufactures book as being factual. Geeee..did it ever occure to you that the same people who wrote this book, also sells replacement tubes?? Maybe ,just maybe they would sell MORE tubes if everyone did this and push them to their max limits? I have played with tubes for the past 45 years, all kinds of tubes from a #10 tube with carbon filaments thru 3CX30000 Eimacs.
It has been my experience, that pushing the tube to the point the plates start glowing red, you have killed the integerity of the tube and it will fail prematurely. As for getter action, this was burned off at the begining of the tubes life, and running it that hot will not remove any additional oxygen that may have leaked in, unless you consider the glass melting, thus reducing the size of the cavity.

Nothing in life works as it was written in a text book. They are ok for reference material, to get a starting place, but once you have gotten some experience under your belt, you learn that text books and real life experiences are different. Any engineer with any experience will tell you that. I have found that you back down the CCA or the ICCA by 5 to 10%, let the tubes run a little cooler that you will get more life out of them, and make about the same power.
The additional energy to turn the plates red is just going up in HEAT, which does it no good what so ever.

73 de W4LGH - Alan
http://www.w4lgh.com





 
RE: Plate Color Facts  
by K6LHA on March 16, 2008 Mail this to a friend!
K8MN (David Heil) started battling the subject and his 'enemies' on 15 Mar 08:

"Alan wrote:"

"First off everybody likes to be right. If you go back and read what was said, it talks about the "PLATE COLOR" @ the absolute MAXIMUM!! This does NOT mean you are suppose to run it this way, as you never run ANYTHING @ its absolute MAXIMUM for full time duty!!!
NOTHING..NEVER! If you do you're in for a fall."

"What was quoted were the terms, "at CCS Maximum or ICAS Maximum". Neither of these is maximum for the tube."
"Tom W8JI has provided factual information. Jim N2EY has provided factual information. You can attempt debate, but the facts are still there."

Correction: Jimmy (N2EY) provided LINKS to what others have written on the Internet. Since he has NO experience with high power RF amplifiers, LINKS are about all that we can expect from him on this subject.
---------
and Len Anderson added:

"Alan, I would only reply that your first sentence should read "everybody HAS to be right."

Especially you-know-who. :-) "

"In this case, Len, it would appear that you are playing the part of "you-know-who"."
---------
Tsk, tsk, big Dave, there you go denigrating old Internet enemies again. :-)

I just related MY personal experiences of long ago. I provided only two LINKS, one of which I wrote myself. Here they are again:

http://sujan.hallikainen.org/BroadcastHistory/uploads/My3Years.pdf

The other link is a digitized copy of a booklet produced by my former Army signal battalion in 1962-1963:

http://sujan.hallikainen.org/BroadcastHistory/uploads/AlphabetSoup.pdf

"The fact is, you've gotten it wrong."

The FACT is, I GOT MY LINKS' INFORMATION RIGHT.

The FACT is, YOU have NO verification on ANYTHING I've uploaded elsewhere and can't cross-check a damn thing. YOUR experience seems totally from amateur radio operating and working for the Department of State in various (small) Embassies in Africa and Finland.

Over the last decade in rec.radio.amateur.policy you've stated very little about ACTUALLY working on vacuum tube POWER amplifiers' design, ratings, whatevers, not even much on what you've manually tweaked the knobs of in operating. Whatever you've mentioned seems to be entirely made by others for the market or for the government. If you've done any personal research into testing RF power amplifiers (whether or not the anode glows), you've never mentioned it and you seem to be a new poster on e-ham (doing the usual newbie thing of posting twice on the same reply).

As to my own personal photo essay (which wasn't originally done for public distribution) I have the backing of Gene Rosenbaum, N2JTV, who was assigned to the same signal battalion I was, at the same time and working at the same transmitter site...plus a final perusal by Mr. James Brendage, a retired civilian engineer (for both USA and USAF) who was also working at that transmitter site when I was assigned there. Jim Brendage kindly sent me a copy of the Signal Corps brochure which I digitized and uploaded to Hal Hallikainen's website (second upload) for the interest of others in radio broadcasting and communications
history. For my photo essay I selected only a small part of my collection of personal color slides (about 600 originally of which only about 500 survived good enough for digitization/repair). I managed to save a few booklets and other paper documentation from my three-year assignment at ADA, but I did get help on some (later) dates of events from Rick Chernitzer of the Tokyo office of the Pacific Stars and Stripes military newspaper; Rick did an 'e-interview' of me on a Hardy Barracks history piece for the 'Stripes (issue
of 10 Sep 2002). Several veterans of Signal Corps service in the central Honshu territory in and around when I was stationed there gave me small items of information to add to my photo essay.

I did not 'save' nor plunder ANY technical manuals of the various transmitters, exciters, teleprinters, frequency standards, receivers, radio relay equipment, etc. and I cannot say, under any penalty for perjury that you wish to put forth, ANY sort of EXACT technical specifications or operating procedures. No, I cannot say - for absolute certainty good for any jury of 12 peers in a courtroom - whether or not the 833s used in the 1 KW transmitters at station ADA glowed red in their anodes when working. Had they done so, I would have noticed it with an illustrator's eye and captured it on film. AT THE TIME my experience with the world was 'tuned' towards the photogenic subjects.

"Either you don't remember correctly your military experience or those tubes weren't being run anywhere near their CCS or ICAS maximum."

Either you've forgotten my recent posting remarking on the UNDER-maximum operation of the BC-339 (as it appeared to me just from the mass of internal components) or you are being your usual denigrate-all-old-newsgroup-enemies self, something you've been doing against others on rec.radio.amateur.policy for the entire debate time over morse code testing in US
amateur radio license examinations. I was NOT the only victim of such public chastisement and denigration...anyone who objected to morse code testing got your treatment.

The 1 KW BC-339 was NOT the 'only' transmitter at station ADA and I mentioned it specifically because it was the most used. In three years I was there, the transmitting equipment was constantly being upgraded. For example, the two old Western Electric pre-WWII
design SSB (commercial 12 KHz format) were being replaced by post-WWII design Western Electric LD-T2s. There would be a total of five of those in use by 1956. Those were 4 KW PEP at HF, 10 preset frequencies having servo adjustment of 12 variables, very quick to
QSY. At least three of those were boosted to 40 KW PEP by Collins Radio 50 KW CW transmitters set as linear amplifiers, those feeding rhombics which were three to four wavelengths long on a leg (depending on frequency). The two Press Wireless 15 KW CW tranmitters were replaced by the Collins units, increasing those circuits' traffic capability from four (multiplexed) TTY to two voice and eight TTY circuits on each SSB transmitter. When I arrived at ADA, there were two Wilcox Electric HF transmitters,
approximately 1 KW RF output used for both AM or FSK TTY. One of those went back to depot and the other one had its modulator section kept from a Signal Office sanctioned experiment in using it as the Far East Commander's aircraft link. All I did was help connect the two units and make sure it loaded up on its antenna (one omni, the other directional) and that the AM linearity was measured correctly (not by any ARRL documentation but by commercial documents and Signal Office information). By 1962 there were MANY changes to both transmitting and receiving and central control sites of ADA, indicated by the 'Alphabet Soup' copy mentioned.

Could I have personally observed any of the finals in those? Only the BC-339s through their small round window in the front and part of the LD-T2 which had windows in most of their individual-stage enclosures. The Wilcox commercial units NO for reasons I've already mentioned in a posting here. The filaments of the PW-15s could be seen through the PA windows but their anodes sat in a tubular housing for their forced-air cooling. The BC-340 10 KW power amplifiers had their finals water-cooled and thus most of those tubes were enclosed and prohibited direct anode viewing.

In checking the VHF radio relay transmitters (those using 829s), opening the Tx lid would allow viewing of the anodes but those remained unglowing while pushing out a heaping 50 W CW (PM from much-multiplied xtals). ADA didn't have any UHF transmitters (from the AN/TRC-8 sets), only receive. The VHF-UHF radio relay needed more incoming circuits than outgoing at the transmitter site. In the 12 W peak pulse microwave terminals the 2C39s were cavity mounted and anodes not visible in the Tx, its driver, and the LOs of the receivers. 2C39 is an 'inverted' lighthouse type with integral cooling fins on its anode connection.

I've not mentioned the AN/GRC-26 mobile HF station, all of those using the venerable BC-610 transmitter (of some later suffix letter after WWII), those being kept by my Signal Battalion as part of the second-stage emergency preparedness protocol, work divided among all the RF companies. There were the first-tier emergency-contingency transmitters at various places (including at the FEC Hq building) which were fired up and checked periodically. The LAST-ditch contingency plan involved ancient AN/GRC-9 CW-AM sets having fantastic RF power output of (maybe) 30 W and powered by armstrong crankers sitting astride the small hand-cranked generator on its tripod legs. The Angry-Nine receivers were so overloaded by all the transmitter RF that NONE of the scheduled test runs were ever completed. Those were eventually scrapped back to the depot, other equipment replacing them including AN/PRC-8 through -10 backpack VHF transceivers. Yes, I had a 'need to know' the emergency contingency plans even though only an E-5 and memorized that as well as anyone...along with every other thing of importance in radio circuits and equipment at both transmitters, receivers, the contingency plan blockhouses and at the control center.

If you want to call me 'mistaken' then you WILL. [that is absolutely predictable based on years of your posting elsewhere] However, YOU don't know spit about that Army activity at the time and aren't about to concede that any no-code-test advocate in amateur radio EVER knows a damn thing about radio. That has now teleported to e-ham articles forum and you are busy, busy making another battle royal over trivial details and ALLEGED 'wrongs.' I KNOW what you are trying to do here and it has LITTLE to do with the spirit of hobby communications in US amateur radio. It's just your own personal spite at work.

Me, I'm just a hobbyist in radio now with a valid US amateur extra radio amateur license obtained legally and without a single waiver. I got my ONLY amateur radio license ever at age 74 with no strain (except missing viewing of the AAA 500 NASCAR race at Fontana, CA that Sunday). I've been a professional in radio for a long time and - just maybe - some of the things I've learned and experienced MIGHT be a help to other hobbyists. You obviously don't think so. Tough on you, Davey. You aren't the Foremost Authority on glowing anodes and neither is N2EY. Quit trying to make out that you are some kind of Judge of What Others Are Permitted to Say.

AF6AY
 
RE: Plate Color Facts  
by K6LHA on March 16, 2008 Mail this to a friend!
K8MN attempted to do more 'anode battle' on 15 Mar 08 with:

"N2EY provided a number of url's showing vacuum tubes in operation."

Well, then N2EY can go argue his own case, can't he? Have you been admitted to the Bar? Does he need Amateur Attornies to 'represent' him? He's got all that 'experience' googling up lots of LINKS.
...........

"The well known Eimac note addressed what could happen if the tube/tubes were lightly loaded. The term "excessive bombardment of the glass" is used by Eimac."

Is it REALLY a 'well known note?' Did you poll all the readers here on that 'known?' :-)

So Eimac wrote something a long time ago. So did MANY other firms writing AppNotes. The wording is still funny, ha-ha, and I commented on that. But, you've never liked anything I've written, expressed, stated in the last decade so your little barb is expected.
..........

"Do you know of any user of broadcast receivers or television sets which had any option of adjusting the loading of a vacuum tube within those receivers?"

Yes. ANYONE with some alignment tools, a Sams Photofact or factory equivalent, and some (variable) knowledge of what is those electronic units. :-)

That's been done for decades by UNlicensed amateurs that aren't hams.
.........

"Do you have any idea of how thick the glass on the face of the typical CRT might be, Len?"

Yes I do. Have you ever observed the ultor on a color TV display CRT to GLOW? I haven't.

Do you know what an 'ultor' is, Dave? [it is one of several names for the final accelerating electrode]

"Do you know what type glass is used?"

No, but if you **** up to Jimmy, he'll send you a LINK to the exact answer...:-)
............

"Incandescent lamps are not vacuum tubes. They are not run at high potential and do not involve RF, but you can bank on the fact that those filaments are glowing--not red, but white hot. You'll never see a thing like suck-in on them. They're made of very brittle glass."

Tsk, tsk, it is YELLOW-ORANGE HOT. Very bright, but it isn't close to WHITE until you get to halogen bulbs. You've not done too much photography in color, have you? Check out your Wratten filters and Kodak handbooks some time. Look for COLOR TEMPERATURE chapters.

CORRECTNESS, Davey, one the super-insistent things Jimmy demands...of everyone...except maybe other morsemen or morseaholics.
...........

AF6AY: "Let's get to the bottom line: YOU don't want ANYTHING contrary to your personal beliefs so you keep up this supposed 'engineering facts by authorities' messaging in order to keep your personal beliefs supposedly valid."

"His personal beliefs? The things Jim has stated are fairly widely known and he has submitted documentation to support his statements."

...and everyone else's statements are 'falsehoods' and 'not documented' if they disagree with his highness, the Foremost Authority? :-)

Jimmy 'submitted' some LINKS to what others have written. I say He's never fired up any high power RF amplifier except in his imagination.
..........

"Jim has been a ham for over forty years. As I recall, you entered amateur radio a little over a year ago."

Oh, oh, THAT old ploy again. :-) Davey, I've been a PROFESSIONAL in radio-electronics since 1952 and FCC LICENSED as a commercial radiotelephone operator for 52 years. I got into HF communications on a massive basis 55 years ago...USING, TUNING, and a few times REPAIRING High Power HF vacuum tube amplifiers.

Good grief, Davey, did you think 'knowledge' about high power HF tube amplifiers exists ONLY in US amateur radio?!? Did you think passing an amateur radio test imbued everyone with absolute 'expertise' in everything about electronics and radio?

What has Jimmy's 'experience' in high power HF tube amplifiers been? Will he supply a LINK to an authoritative source for that? One that is good enough for a court? :-)
..........

"Your recent experience in high power RF appears to have been over a half century ago."

It's the main thing I've got public. It has no Non-Disclosure Agreement attached and it does not violate any US Code in regards to treason or copyright infringement nor does it break any corporate trade secrets. What ever it was, you would NOT like it, regardless of subject. That's as predictable as the sun coming up tomorrow.

The end of my (voluntary) military service did NOT end my relationship to high power RF. The OBSOLESCENCE of the vacuum tube for MOST HF to UHF power amplifiers did that. :-)

Yes, Davey, broadcasting still uses tubes in final PA stages for below-VHF transmitters, but not near as much as you imagine. The modular solid-state transmitters have taken over for NEW transmitters and with increased reliability and much less need for monitoring by the meter readers with FCC licenses. In fact, most transmitters in that category don't even NEED licensees to operate them.

TV transmitters use a variety of power amplifier types with power klystrons leading for UHF TV, both NTSC and DTV. Commsats like TWTs (nearly all fully enclosed so nobody can check the glow on their collectors). Magnetrons have been made by the millions now. With RF powers of 500 to 1000 W they easily qualify as POWER RF devices. But, since they operate just above 2 GHz, you dismiss them as 'unimportant' because they don't work at THE BANDS (amateur HF). Have you peeked in on working maggies, big Davey? Do their anodes glow?

"Why not outline your more recent experience with high power RF, Len.

That stopped in the 1980s, Davey. Sorry, but it was covered by NDAs. No can do.

Why not outline Jimmy's (N2EY) recent experience with high power RF, Davey?

He assumes the mantle of Foremost Authority. So do you in constantly talking down to your supposed 'inferiors.'
...........

"Do you own a high power, vacuum tube amateur radio amp which runs high power?

No. That's NOT a requirement of my license. I have a nice Icom IC746Pro which is all solid-state. It's a tenth of a 'full gallon' (in ham speak) on HF and adequate for my use.

Does Jimmy (N2EY) own/have/scrounged a high power vacuum tube amateur radio amp which runs high power? Geez, Davey, good ol' Jimmy has already spoken of the marvelous wondrous Elecraft K2...and its follow-on, the K3. Supposedly Jimmy has a K2 although we can't be sure since he speaks so much about his 'famous Southgate Type 7' which is all-tube. NONE of those are 'high power' in the ham sense.

Strange, I couldn't find a single link to any description of a 'Southgate Type 7' on a web search of 30+ plus pages of hits...except for Jimmy's AOL home page. There's a Southgate suburb of London which as an ARC and there are several cities in the USA named Southgate (the one in California is one of the largest of those).
...........

"One of the 833's weaknesses is in the seals of the metal to glass points. What you experienced in the military may have been such a failure. It may not have been suck-in. In the suck-in, the glass actually begins to melt. It is visible as such."

Earth to Davey: Hello, Davey, do you read me? Obviously you don't. I related a little story of what happened at station ADA when a BC-339 was NOT properly neutralized by someone on another shift. The 833s in the final took off and oscillated and the anodes got so hot it DID SOFTEN THE GLASS UNTIL IT COULDN'T HOLD BACK THE OUTSIDE AIR PRESSURE. One of the 833s just cracked apart but the other one had nice little inverted volcano shapes pointing into the approximate center of the anodes. The OIC had someone mount it on a piece of wood and had it mounted on the central console of the transmitter house as a display. Every shift coming on duty had to pass by it. We all got the implied message of that display.

There might have been up to 30 833s at work in station ADA at one time and NOT ONE suffered what you, Jimmy, and (supposedly) Eimac call 'suck-in' except for that one un-neutralized-on-a-QSY transmitter. If you knew so much about certain tubes in HF power amplifiers, why didn't YOU contact the DoD and offer your 'expertise' on tube failures?

Since that incident I related occurred during another shift (we had four teams), I cannot state categorically that the cause of that failure was not due to 'glass-metal-seal-failure.' But, note that BOTH 833s went bye-bye, not just one. Failure of BOTH due to seal failure seemed unlikely. The cause of failure was decided by the Officer-In-Charge (OIC, in that period was Capt. William Boss, a licensed radio amateur in addition to being a career officer), the assistant OIC (1st Lt. Riewerts), maintenance NCOIC (MSgt Ouye), and civilian engineer Jim Brendage. I took THEIR word of it at the time. So did the Chief Signal Office, based on a report that was accompanied by photographs taken by A Company of our Battalion.

In tubes there ain't no such thing as 'suck-in.' Since they are vacuum inside, the outside air pressure PUSHES IN the glass. Amazing but true. CORRECTNESS, DavEy, CORRECTNESS. that is one of Jimmy's absolute insistences of everyone. :-)
...........

"Try to behave in a civilized manner."

Suck it up, Davey. Wow, one can't make an idle statement about personal experiences in this article forum until Judge Heil picks up his (unauthorized) gavel and 'sentences' all those who disagree with Jimmy (or himself). Oyez, oyez...

AF6AY
 
RE: Plate Color Facts  
by K6LHA on March 16, 2008 Mail this to a friend!
W4LGH replied to a Foremost Authority on March 15, 2008:

"Well here we go again with using was is published in the manufactures book as being factual. Geeee..did it ever occure to you that the same people who wrote this book, also sells replacement tubes?? Maybe ,just maybe they would sell MORE tubes if everyone did this and push them to their max limits? I have played with tubes for the past 45 years, all kinds of tubes from a #10 tube with carbon filaments thru 3CX30000 Eimacs."

Alan, some folks take advertisements as Gospel. If a sticker on the back of a radio said 'replace with genuine *** brand tubes' then some would BELIEVE it with all their heart and insist on that being TRUE. Marketing types bank on that gullibility...and it does work to some extent. :-)

What you say makes SENSE on an empirical level. We've both grown up during the vacuum tube era and seen it, experienced it on a factual level. The biggest cause of failure of vacuum tubes has always been filament failure. Three to four decades after tubes had been in production, the tube makers finally got around to making filaments that could last longer than regular tubes...and charged nearly double per tube for the SAME internal electrode structure. They got away with such pricing because transistors had not yet made any inroads on their market demand for replacements.

Not being an 'expert' on high power tube amplifiers, but knowing a few simple things about cleaning up vacuum in smaller tubes, I find it very hard to believe that GETTERING has to depend on power tube anodes glowing red-hot. Maybe it does, but maybe it doesn't. Very very few of the correspondents in this forum have actually made power tubes. Those that did were in a very narrow niche activity even during the vacuum tube era. If they DID use the anode as a GETTER then it seems to me that they were doing cheap construction. Induction heated getters could be separate structures within a tube, just like they are in smaller, lower-power, cheaper tubes.

But, that is just my supposition. A couple of Foremost Authority types from rec.radio.amateur.policy will no doubt blast me with all sorts of invective and demand I look at their links...to prove They are 'right.' :-)

73, Len AF6AY
 
The Care And Feeding of Power Tetrodes  
by N2EY on March 16, 2008 Mail this to a friend!
Excellent Eimac publication on their products. Can be downloaded free from:

http://bama.edebris.com/download/tubesandvalves/eimaccfpt/eimaccfpt.PDF

9 MB PDF file, lots of good info.

73 de Jim, N2EY
 
RE: The Care And Feeding of Power Tetrodes  
by W4LGH on March 16, 2008 Mail this to a friend!
The getter material coating of the plates on hi-power tubes has been pretty common. However these tubes do come with instructions to "Break them In". It is this process that removes any final gasses in the tube. Once this break-in has been done, there is no more getter material left on the plate, and the tube is ready to be put in service. If this break-in is not followed you run a high risk of early tube failure.

As for tubes verses light bulbs...Tubes MUST run in a vacuum, or the electrons won't flow correctly. Light bulbs do NOT have to be in a vacuum, and can be filled with an inert gas like nitrogen and will still work.

Filament failure was a problem in the early days, but they worked that out pretty good. In the case of hi-power triodes, the filament is the cathode, so it is built very heavy to handle the hi-drive its got on it.
This is why most power triodes take 8 to 15amps of current to light them up. Filament failure is very un-common, and these tubes are almost instant warm-up, usually about 3 seconds.

The last major breakthru in tube technology was the Nu-Vista tube ,developed by RCA. However transistors were coming into their own @ that time, and an entire line of Nu-Vistas were dropped.

73 de W4LGH - Alan
http://ww.w4lgh.com
(lots of new updates on my site)



 
RE: Plate Color Facts  
by K8MN on March 16, 2008 Mail this to a friend!
W8MN copied and then said..."Alan wrote:

There's no W8MN here, Alan. I'm K8MN

"First off everybody likes to be right. If you go back and read what was said, it talks about the "PLATE COLOR" @ the absolute MAXIMUM!! This does NOT mean you are suppose to run it this way, as you never run ANYTHING @ its absolute MAXIMUM for full time duty!!! NOTHING..NEVER! If you do you're in for a fall."

W8MN comment...

K8MN

"What was quoted were the terms, "at CCS Maximum or ICAS Maximum". Neither of these is maximum for the tube. Tom W8JI has provided factual information. Jim N2EY has provided factual information. You can attempt debate, but the facts are still there."

I gather that since you had no comment, you've decided that the CCS and ICAS figures are not the absolute maximum ratings for a vacuum tube.


and Len Anderson added:

"Alan, I would only reply that your first sentence should read "everybody HAS to be right." Especially you-know-who. :-) "

In this case, Len, it would appear that you are playing the part of "you-know-who". The fact is, you've gotten it wrong. Either you don't remember correctly your military experience or those tubes weren't being run anywhere near their CCS or ICAS maximum.
=================================================

Alan:
"Well here we go again with using was is published in the manufactures book as being factual."

We could probably come up with some sort of conspiracy theory on the part of vacuum tube manufacturers. My automobile came with a manual. Should I assume that ratings printed in it should be taken with a grain of salt? Do I assume that the manual which came with my riding mower has written specs much higher than the actual capabilities of the mower?

Alan:
"Geeee..did it ever occure to you that the same people who wrote this book, also sells replacement tubes??"

The companies which produce tubes, sell tubes. They'll sell you an initial tube or a replacement tube.

Alan:
"Maybe ,just maybe they would sell MORE tubes if everyone did this and push them to their max limits?"

I've seen nobody advocating pushing tubes to their absolute limits.

I have played with tubes for the past 45 years, all kinds of tubes from a #10 tube with carbon filaments thru 3CX30000 Eimacs.

You may have a bottle which will make you a fortune--the only type 10 tube with a carbon filament!
All those that I have or have previously seen have tungsten filaments.

Alan:
"It has been my experience, that pushing the tube to the point the plates start glowing red, you have killed the integerity of the tube and it will fail prematurely."

If you use the amplifiers you previously mentioned, used under the circumstances previously mentioned, the tubes in those amps are showing some red at least during voice peaks. It sounds as if you are unaware of it.


Alan:
"As for getter action, this was burned off at the begining of the tubes life, and running it that hot will not remove any additional oxygen that may have leaked in, unless you consider the glass melting, thus reducing the size of the cavity."

Have it your way, Alan. The manufacturers must be wrong.


Alan:
"Nothing in life works as it was written in a text book."

I have to disagree.

Alan
"They are ok for reference material, to get a starting place, but once you have gotten some experience under your belt, you learn that text books and real life experiences are different. Any engineer with any experience will tell you that."

W8JI gave you some information which you've chosen to ignore. He's an engineer with lots of high power linear amplifier design experience under his belt.

Dave K8MN
 
RE: Plate Color Facts  
by W8JI on March 17, 2008 Mail this to a friend!
I'm not suprized to see false statements or bad ideas, like statements that "tubes with getters on the anode are a cheap design" or the implication a large glass tube needs gettered only once at activation.

I suppose such comments stem from a incomplete understanding of how a large power grid tube works and how and why they are manufactured like they are.

Almost anyone with any time and a computer can reseach gettering materials to see how they work. There is also seal information on the web.

Gettering throughout the life of a tube is necessary because the materials inside the tube outgas over time, and because seals leak. It is especially difficult to get a good glass/metal bond when the seal has a large surface area. This is why the seals are always the minimum possible diameter.

When they are very small hard wires like a receiving tube, they can use a long seal area and get a pretty good bond. When they are leads carrying 15 amperes or more or supporting a very heavy internal element that has to be held precisely in position, the seal area is so large even a very small leakage per mm is a big problem.

This is why tube manufacturers use high temperature getters in high power tubes. In ceramic external anode tubes the only spot hot enough (at red heat) to run the getter is the filament. There is often a heat dam area that has a reasonably large gettering material near the hot filament.

In most glass high power tubes it is more effective to coat the gettering material on the anode. The most common coating is a light powder gray color coating called zirconium.

It isn't rocket science or obscure how there materials work. It is all over the Internet in scientific papers, as well as in technical libraries. All one needs to do is search columbium, titanium, tantalum, tungsten, zirconium, or molybdenum or any of the gettering materials required to maintain a vacuum in a large high vacuum device.

The material of choice due to its wide range of absorption, cost, and ease of use is zirconium which has peak performance at around 1000 degrees C. It only just starts to getter at several hundred degrees. This is used in all of Eimacs and many of Amperex and RCA's glass internal anode high power tubes.

8877's (ceramic tubes) use tantalum near the filament near the filaments, so they getter by filament heat.



All gettering meterials commonly used in high power tubes require large amounts of heat to activate. It's terrible advice to tell people a little anode color isn't necessary for maximum tube life in tubes using moly anodes or anodes with zirchonium coatings.

73 Tom

 
RE: Plate Color Facts  
by WB8NUT on March 17, 2008 Mail this to a friend!
Tubes and other old, outdated junk....yawn....where's the nearest landfill?
 
RE: Plate Color Facts  
by K6LHA on March 17, 2008 Mail this to a friend!
K8MN posted disagreeably on 17 Mar 08:

"Alan [W4LGH]: "Nothing in life works as it was written in a text book."

"I have to disagree."

You have a long habit of disagreeing with others (with some exception of other morsemen). Most folks would put you down as just plain disagreeable. <shrug>

.........

"Alan [W4LGH] "They are ok for reference material, to get a starting place, but once you have gotten some experience under your belt, you learn that text books and real life experiences are different. Any engineer with any experience will tell you that." "

"W8JI gave you some information which you've chosen to ignore. He's an engineer with lots of high power linear amplifier design experience under his belt."

You are NOT an engineer nor have you any experience in designing high power RF amplifiers (linear or non-linear). You should not attempt chastising others' technical advice until you've advanced beyond just the collecting of old vacuum tubes.

I AM an engineer in electronics design but have not worked with linear RF power amplifiers (only non-linear) and have not designed or manufactured any vacuum tubes. As a USER of both such devices, Non-Linear (based on their average power) was up there with the linear types. Peak powers have specific conditions in addition to worries about sealing (which has never been any significant worry in any design reviews I've heard about). But peak power conditions do not apply much to amateur radio communications carried out in "The Bands" (meaning HF only for non-amateurs).

As to "manufacturers making mistakes in their documentation," YES, SOMETIMES THEY DO. That is why 'errata' sheets are published and distributed as soon as a document is discovered to contain a mistake. Live with that. I've had to for a half century in order to keep a paycheck coming regularly (unlike some government workers).

You might want to check the TOC of QST sometime and take note of a-now-almost-regular occurrance of CORRECTIONS which may be 3 to 4 months old. [ARRL is a manufacturer of publications, not vacuum tubes or electronic hardware] Periodicals of the electronics trade ['controlled circulation' types one can get free if one is in the business] have the same problems. MISTAKES HAPPEN.

Alan remarked "Nothing in life works out as it is written in a textbook." That is a METAPHORICAL statement, an observation, perhaps a satirical comment. If you want to remain disagreeable then you must continue to take such 'throwaway' lines as LITERAL. I doubt that Alan meant it literally. MY particular life (so far) has NOT been 'textbook' in that it was NOT in the 'accepted' or 'official' linear-progression of things and I've been openly chastised in amateur radio forums (by yourself, certainly) for 'not doing things as I was supposed to do them.' [there's lots more in my human experience side, non-radio, but that isn't for this forum]

You ought to recognize that certain phrases, such as 'textbook', aren't always to be taken literally. Such phrases can be simply commentary on some who MUST take everything literally as it is described. Those aren't the adventurers or the experimenters or those who don't 'push the envelope' (a phrase regarding exceeding performance profiles commonly called an 'envelope' that one must stay IN).

The intended subject of this article forum was VACUUM TUBES. Now, it is a safe bet that FEW in here have ACTUALLY MADE THEIR OWN VACUUM TUBES or even MADE THEM AS MANUFACTURERS. I haven't. I've never made any semiconductors, either, yet I've had some experience in design and building of RF power amplifiers using those. Semiconductors are NOT based on working in a vacuum and have their own unique properties. Let's face it, regardless of personal love of such devices, the longing and other emotional nostalgia over 'tubes', vacuum tubes are becoming OBSOLETE. They are used now only in niche applications in all of electronics. To get into disagreeable internecine warfare - just for the sake of arguing (or proving what a great and glorious person one is) - certainly for dragging over old personality conflicts from other, previous venues - is nonsensical. It is 'counterproductive.'

Have YOU made your own vacuum tubes? Have you made an in-depth study of gettering in hard vacuum environments? No? OK, join the rest of the crowd in here. Have you chastised others for not doing things as they are 'supposed to be done?' Yes, you have. [join the rest of the crowd in here on that since so many do that] Have you 'pioneered the airwaves' in advancing the state of the radio art?' No? OK, join the crowd on that, too. :-)

I've done very LITTLE design or building of vacuum tube circuits since around 1980, a period of just a bit over a quarter century. I KNOW - in general - how they work (including some that aren't used in US amateur radio) and all I can relate is some observations and actual, life experience in USING some high power vacuum tubes. Some in here are terribly offended by that (at least in words), trying to push some personal agenda of theirs. Why? Vacuum tubes are going away in electronics technology. It is inevitable. Yes, they launched PRACTICAL radio communications, no denying that, but that doesn't mean they will 'always be with us' or that we should devoutly revere their existance forever more.

AF6AY
 
RE: The Care And Feeding of Power Tetrodes  
by K6LHA on March 17, 2008 Mail this to a friend!
W4LGH remarked on 17 Mar 08:

"...The last major breakthru in tube technology was the Nu-Vista tube ,developed by RCA. However transistors were coming into their own @ that time, and an entire line of Nu-Vistas were dropped."

Ahem, the Spelling Police will get on your case, Alan. :-) :-)

The trade name was Nuvistor and one division of RCA Corporation made much PR about them (I think it was the old Harrison division) but, oddly enough, the solid-state folks at Sommerville (?) were just releasing their 'COSMAC' line...which became the standard logic family that most call "CMOS" now. Nuvistors ceased production long ago. CMOS, junctions and internals much, much improved are now ready to take over as the preferred digital logic family, are going to displace venerable TTL.

'Nu-Vista' and 'New Vista' are probably trade names for other things or services. No matter, really. Only the PURISTS will want to e-fight over what is 'correct.' :-)

There might be an argument over the 'last' type of vacuum tube, namely by those who got all orgasmic over the 'Compactron,' another last-ditch attempt to capture consumer electronics market for tubes. ["imagine just using ONE tube for everything!" was one sales pitch I heard way back when] I neither know nor care about who came out with the Compactron first, only that its debut was about the same time as the Nuvistor. Those were basically the same sort of internal structure but with an entirely different envelope (Nuvistor) or up to three different tube functions stuffed into a larger glass envelope (Compactron) and with an entirely different base pin arrangement for each (needing special sockets). Both were done to attempt an eleventh-hour forestalling of the coming expansion into solid-state active devices into consumer electronics stuff. Didn't work.

One can't see the anode in a Nuvistor (metal body) and I've never known a beam-power section of a Compactron having its plate glowing red as the 'perferred' anode mode. :-)

What I find most interesting is that there's still some sort of building-interest in single-tube whatsis and a few endorsing Compactrons...especially so when those have been obsolete for new designs three decades ago and more and those boosters are in their forties. A 'one-tube transmitter' made with a Compactron can combine two older tubes into a working MOPA type Tx of low power but, being rock-bound, it doesn't QSY easily. A super regenerative receiver can use a single Compactron with added attraction of audio amplification...but regeneratives on HF are still just the same old regenerative receiver. Apparently those devotees have way too much nostalgia or learned their radio smarts via OLD, OLD publication material. If they really LIKE that kind of thing, fine, but its for them and NOT for any improvements of the state of the art in radio. <shrug>

73, Len AF6AY
 
RE: Plate Color Facts  
by K6LHA on March 17, 2008 Mail this to a friend!
W8JI was terribly offended by some postings and remarked on 17 Mar 08:

"I'm not suprized to see false statements or bad ideas, like statements that "tubes with getters on the anode are a cheap design" or the implication a large glass tube needs gettered only once at activation."

"I suppose such comments stem from a incomplete understanding of how a large power grid tube works and how and why they are manufactured like they are."

"Almost anyone with any time and a computer can reseach gettering materials to see how they work. There is also seal information on the web."

Good grief, Tom, you are beginning to sound like you take EVERY REMARK of others as LITERAL.

For one thing, I've never even tried to make my own vacuum tubes, much less try to go into competition with Svetlana. I've never even tried to make my own semiconductors, either. :-)

Has anyone else in here (besides yourself) done that?

The 'web has a great deal of information available, yes, but SOME of that information is far from factual and there is NO governing body that 'proves out' every statement as 'truth.' That applies to Wikipedia as well, much as that disturbs others.

In roughly a half century of engineering in my experience, I've not had any Internet to refer to, only manufacturer's datasheets and documents. [Internet went public in 1991 and I had no access to it until 1993] Yes, I've gotten lots of information via the Internet to add to about 38 lineal bookshelf feet of printed documentation in my home office. But, let's look at what all that information IS:

MOST electronics information concerns circuits and systems where neither vacuum tubes nor semiconductors HAVE to be constructed. We buy them all ready-made. Not every circuit application requires HIGH POWER capability although that is a sometimes a subjective term applying to one particular discipline in electronics. Vacuum tubes for power applications might be rated for such-and-so operating hours and we can only go by such guidelines.

Since I began designing electronic circuits for work, I am very used to reading EVERYTHING on a tube's datasheet. I would like to point out that MOST 'low-power' tube characteristics are TYPICAL. The range of 'typical' in percentages are hardly ever given by any tube maker. That was carried over to semiconductor datasheets as well; early semiconductors (particularly diodes) had whole families made as part of the same lot and electronically graded LATER just prior to part number identification. The FACTUAL data presented in just about all active-device datasheets is largely of a GENERAL specification form and NOT cast in concrete with armor overlay. Only the absolute minima and maxima of specifications can be trusted but I KNOW that some manufacturers HAVE exceeded maxima stated for smaller vacuum tubes, in particular early National Radio and Hallicrafters 7" TV receivers. My first TV Set was a National and it used twin triodes as sweep amplifiers for the electrostatic deflection CRT, running them at plate voltages far exceeding 'official' tube data. From schematics viewed elsewhere, the Hallicrafters model was roughly the same. While neither made any significant market penetration for TV sets, it showed that some designers could 'push the envelope' well before that phrase entered common speech. Would *I* have done that? Probably not without some extensive testing on the bench to prove both life and replaceability with many brands of the same tube.

Radio amateurs don't usually have any 'hard' vacuum facilities nor do they have time to do extensive testing of seals during life tests and I seriously doubt if more than a handfull have access to any metrology equipment to seriously examine the qualities of hard vacuum (extraneous gasses, particles, etc.) or its effect on various metals used within. Nearly all of just BUY or scrounge vacuum tubes all ready-made. All we have to go on is manufacturer's information - and the input of others who've actually used certain power tubes in certain applications...the latter requiring some 'reading' of those others to gauge how much they REALLY know about certain minutiae of vacuum tubes.

As I've said, I've never MADE a vacuum tube in my life (even if I've 'pulled a hard vacuum' for some research experiments done by some physicists). What I related was personal experience with just a FEW power tubes for HF obtained through daily operation a half century ago. But, I've seen and handled thousands of smaller tubes in various electronics and talked to hundreds of factory representatives, even at a couple of specialty vacuum tube companies. But, I was remarking, as Alan, W4LGH, was, on DISSIPATED POWER, as distinguished by glowing anodes. Dissipated power is HEAT and it isn't going out to any antenna. Heat affects all nearby electronics and raises their operating environment. As a general rule, Wasted heat does very little good for other electronics equipment.

Since I've handled so many small tubes and found out that many of them are gettered via RF induction heating, it seemed reasonable to assume that the same would apply to larger tubes. Just an assumption, understand, NOT a categorical 'fact'. The alignment of electrodes in small tubes is just as finicky a production problem as with bigger tubes, yet the small tubes were produced en masse for a lot less market cost. I understand that there is MUCH more market demand for smaller tubes than big RF power handling tubes, but I'm not using that criterion. The 'en masse' production is...and the YIELD of making so many being as high a percentage as possible.

Your statement that power tube manufacturers used a heated anode as a combination of tube plate and getter is reasonable by itself, BUT, that heated-up anode is also going to produce wasted heat (largely in IR frequencies not the RF Hetzes going to the antenna). I can understand cutting manufacturing costs by such an internal design, but I will not say I consider it 'best.' Look at the old shadow-mask type of color TV displays (vacuum state CRTs). An old 12" black-and-white CRT from an old RCA 630TS line has MORE vacuum space than any PAIR of 833s. The vacuum space of a 21" diameter shadow-mask color CRT is much larger and there are three to four distinct seals, all but one around the faceplate joining area. None of those CRTs seem to suffer any 'suck-out' with an electron beam ultor power of only about 12 W average (24 KV and 0.5 mA). They don't have any glowing anodes. Those CRTs are also fairly long-lived with the major problem again of filament burn-out...and they have three electron guns, not just one heated cathode. Note: Add to their production problem the necessity of fine alignment of the shadow mask relative to the phosphor dots on the inside of the faceplate. [exactly how they do that in Taiwan I do not know other than the seals are hot enough to allow mechanical alignment when it is done]
..............

W8JI: "Gettering throughout the life of a tube is necessary because the materials inside the tube outgas over time, and because seals leak. It is especially difficult to get a good glass/metal bond when the seal has a large surface area. This is why the seals are always the minimum possible diameter."

As I said, that's a reasonable statement. However, it should also be noted that the vacuum space of a 21" color CRT estimates out as quite large. [a medium-sized trigonometry problem but one can get close] That turns out to be bigger than a pair of ANY power tubes used in legal-limit HF power amplifiers by radio amateurs. Note also the material exposed directly to that vacuum...interior ultor coating, the metal shadow mask and its framework, three electron guns not just one. Yes, the FINAL seal of those at their back end is quite small with 'fine wires.' Consider just how much TV sets are on in the average household and that is quite large, probably exceeding the number of hours spent by the average ham in operating his HF power amplifier. <shrug>
...........

W8JI: "It isn't rocket science or obscure how there materials work. It is all over the Internet in scientific papers, as well as in technical libraries. All one needs to do is search columbium, titanium, tantalum, tungsten, zirconium, or molybdenum or any of the gettering materials required to maintain a vacuum in a large high vacuum device."

True enough, but is that something ESSENTIAL for the average radio hobbyist to know?

I know how to pronounce molybdenum properly and also pronounce diallyl phthalate properly. That's just not a requisite bit of knowledge to use in QSOs. :-)

Not many of us are going to be MAKING our own power tubes, much less trying to pull and maintain a hard vacuum inside our bottles. As I said, we usually BUY or scrounge final PA tubes...if we use tubes at all in those amplifiers.

Judging by all the ham shack pictures, advertisements, etc., over the last two decades in US amateur radio, the average HF operator has 100 W RF output HF transmitters. That is within the recommended guidelines of the FCC in "using only the RF output power needed to make a radio contact." <shrug>

BTW, I've actually worked with rocket scientists. At Rocketdyne Division of Rockwell (now a Division of Boeing). Some of their lasers use very specific vacuum and gas mixes in volumes that are larger than the largest MF to UHF BC transmitter tube volume (exterior, not just the interior). Just offhand, without researching it, I'd say that the amount of 'rocket science' available over the Internet exceeds that of gettering of vacuum tubes. <shrug>
..........

W8JI: "All gettering meterials commonly used in high power tubes require large amounts of heat to activate. It's terrible advice to tell people a little anode color isn't necessary for maximum tube life in tubes using moly anodes or anodes with zirchonium coatings."

OK, so Wasted Heat is 'good' and lots of us are 'terrible advisors.' Would it make you feel any better if I promise to never, ever again turn on and operate any vacuum tube RF power amplifier in my life? :-)

73, Len AF6AY
 
RE: Plate Color Facts  
by W8JII on March 18, 2008 Mail this to a friend!
Len-----I don't see anything in Toms' posts that would indicate that he was "terribly offended". Sometimes he seems frustrated and even annoyed at some of the misinformation posted. I think Tom does a great job clearing up some of these misconceptions.
When it comes to Rf Amplifier design and Antennas I think he's extremely qualified. 73, Ron
 
RE: Plate Color Facts  
by K6LHA on March 18, 2008 Mail this to a friend!
W8JII posted about a friend on 18 Mar 08:

"Len-----I don't see anything in Toms' posts that would indicate that he was "terribly offended"."

OK, see his last posting, last sentence, namely: "Its terrible advice..." QED.
........

"Sometimes he seems frustrated and even annoyed at some of the misinformation posted."

OK, the rest of us might be that way, too. Ever think of THAT?
........

"I think Tom does a great job clearing up some of these misconceptions."

So far, all he's concentrated on is gettering. All well and good but, as I said, few of us in here have ever MADE our own power amplifier tubes. I haven't and am not ashamed to say that. Neither have I researched and designed anything in the way of vacuum tube power amplifiers for HF. For other ranges of the spectrum where I've worked, the high power tubes had ALL their electrodes hidden from sight. If those tubes glowed or didn't glow their anodes could not be determined. However, their voltages and currents were within spec and the customers were satisfied.
........

"When it comes to Rf Amplifier design and Antennas I think he's extremely qualified."

Good on that. OK, your favorites and unfavorites have been noted.

73, Len AF6AY
 
RE: Plate Color Facts  
by W8JI on March 19, 2008 Mail this to a friend!
I think Len is just trolling.
 
RE: Plate Color Facts  
by W8JII on March 19, 2008 Mail this to a friend!
"Neither have I researched and designed anything in the way of vacuum tube power amplifiers for HF"...........I guesss that pretty much says it all Len. You're not qualified to have an opinion to put you on equal footing with Tom. It's OK though Len I'm not "terribly offended" because I realize it's possible to recognize "terrible advice" without being "terribly offended". Actually I find your post quite amusing-------------73, Ron
 
RE: Plate Color Facts  
by NI0C on March 19, 2008 Mail this to a friend!
AF6AY expressed concern "that heated-up anode is also going to produce wasted heat (largely in IR frequencies not the RF Hetzes going to the antenna)."

Len, in tube amplifiers such as those using the 3-500Z, that wasted heat is actually pretty small compared to the energy sent to the antenna. Might as well use that heat energy to help extend the life of the tube.

Check out the efficiency of an Ameritron AL-80B amplifer, for instance. As I recall, it is on the order of 70%.

73,
Chuck NI0C
 
RE: Plate Color Facts  
by K6LHA on March 19, 2008 Mail this to a friend!
W8JII got out his mortar and testle, replying:

"Neither have I researched and designed anything in the way of vacuum tube power amplifiers for HF"...........I guesss that pretty much says it all Len. You're not qualified to have an opinion to put you on equal footing with Tom."

How are YOU 'qualified' to rank my qualifications? You are a retired pharmacist...which doesn't involve a great deal of vacuum tube power amplifier activity. <shrug>

I've been a pro in electronics (and radio) full time since 1952. Even though I've been commercially FCC licensed since 1956, I've been licensed in US amateur radio since a year ago. Does 'tenure' in licensed amateur radio suddenly, magically, impart some kind of smarts on vacuum tube power amplifiers the minute one is officially licensed as an amateur? I say *NO*. NO WAY. :-)

For that matter, why all this concentration on vacuum tube power amplifiers? I can understand the fuss and fury of some about them. Those were once a big-ticket item for amateur machismo through more Watts. since those are one of the simplest add-ons to a receiver-transmitter combination. Some take that single power amplifier add-on as very, very personal. An RF power amplifier is really a simple circuit; it is not complicated (technologically speaking). NONE of us can control the gettering process in those vacuum tubes unless we MAKE them ourselves. Who does that in here?

One of the great breakthroughs in electronics technology was the invention of the three-element vacuum tube. It enabled all sorts of circuits and systems using that controlled-conductance active device. But, the nature of its operation depended on a VACUUM and very very few amateurs (let alone professionals) had any equipment (or experience for the most part) to MAKE their own vacuum tubes. It took years before repeatable production could be developed in the vacuum tube industry so that (relatively) inexpensive (low-power) vacuum tubes could be purchased over the counter by anyone...and with reasonable assurance that their operation would be as stated in manufacturer's data descriptions.

The second big breakthrough in electronics was the transistor junction (inarguably more important than that first 'audion') and the integrated circuit which inexorably followed. But, manufacturers had a bigger hurdle to overcome in semiconductors, namely the ability to make - and control - the purity of the semiconductor substrate. That and the junction structures (layer by layer) took more years than the first two decades of vacuum tubes. Semiconductor design AND manufacturing DID advance and leap-frogged past the limitations of vacuum tubes in all but the niche areas (RF power amplification, display devices, photomultipliers and certain sensors to name familiar ones). Just on names of semiconductor 'greats,' US amateur radio community will probably NOT recognize names such as Jean Hoerni, Hans Camenzind, or Robert Widlar (just a few that come to mind, there are dozens more). Yet most amateur radio equipment of today DEPENDS on some of the products they designed and developed. As far as I know, those three were not granted amateur radio licenses and that fact should be irrelevant when speaking of the whole of electronics technology.

Vacuum tube technology made radio communications PRACTICAL. Practical in the sense that spectrum-hogging, inefficient damped-wave oscillation ('spark') was no longer needed. Practical in that the insensitive 'crystal set' was displaced by a vacuum tube based receiver that could listen to signals a mere microvolt at the antenna. But, however extraordinary such developments were, tube technology was displaced by solid-state technology. Vacuum tube POWER AMPLIFIERS are becoming a thing of the past. Despite the 'greatness' of some of its design practitioners, it is becoming (if not already here) a relic technology. Emotional upset over that is understandable but that is something I will neither accept blame for, nor attempt to cure in mindsets rooted in the PAST technological eras. About the only thing that vacuum tube power amplifiers can shine about is their present-day, relatively-inexpensive (when compared to longer-lived solid-state types) costs on MF through low VHF. That part of the EM spectrum is generally taken as 'the only place' for ham radio by so many hobbyists. [the internationally-allocated EM spectrum extends from 9 KHz on up to 300 GHz and HF with its 'ham bands' is a tiny, tiny part of that whole spectrum range]
............

"Actually I find your post quite amusing-----------"

No sweat to me, old-timer, I find yours HILARIOUS. :-) It is quite 'standard' in the ham-speak of these venues, of choosing sides and general bragging rights and being put-out by some folks' postings and the denigration of others (without having any personal qualifications to do so).

Since getting interested in electronics technology in 1947 I've observed, first-hand, a truly multiple-plateau-jumping evolution in technology (including 'radio' which is considered a subset of the whole world of electronics). I've been IN part of electronics as well as a consumer who has enjoyed all the advancements anyone could have. I got INTO HF radio communications full time in 1953 (55 years ago) tuning many a high-power vacuum tube power amplifier in a large HF radio communications station. Now, I don't consider myself any kind of 'expert' on tube power amplifiers, certainly not 'gettering' of vacuums within them. However, I've listened and learned from the old-timers (of then) and simply passed on my observations...and done as they say.

No one professional IN vacuum tube power amplifier design could have possibly acquired experience on ALL that were available for MF-HF in their lifetime. The number of licensed radio amateurs who were ALSO engaged in professional work on their design are very, very few in number. I say fine on those who have done so but I do not place them on sacred plateaus of electronics genius because of knowledge of or practical work on making 'clean vacuums' in such tube interiors. Vacuum tube circuitry involves MUCH MORE than just high power amplification. If we are to look at (and possibly salute) ALL vacuum tubes, including a few which also have certain gasses within their vacuum, then we will find that RF power amplification is a tiny part of that whole.

Electronics display technology has already evolved into LED-LCD-Plasma-MEMs that does not require vacuum environments. Most of the sensors and detectors of low-wavelength infra-red to deep ultra-violet have evolved into many and various semiconductor types; the image orthicon and vidicon 'camera tubes' have been displaced by multiple CCDs on a chip and have become consumer item products operable by unlicensed, very-amateur consumers. TWTs (Traveling Wave amplifier Tubes) of moderate RF power output continue to be mainstays of very wideband commsats but the broadcast transmitters of LF through VHF are being designed and made with modular, 'hot-plug' replaceable solid-state amplifiers, displacing their vacuum-based older functional counterparts. Modern 'radio' communications no longer has to contend with the vagaries of the ionosphere for 'DX.' Indeed, DX now extends millions of miles to outer planets of our solar system. Using solid-state 'radio' technology.

So, Ron, if you want to get all hot and bothered over tube technology and its 'experts,' feel free. It might be a bitter pill to swallow for retired pharmacists but change and evolution is going on all around you. <shrug> You need to look at the WHOLE instead of the hole of limited application.

73, Len AF6AY
 
RE: Plate Color Follies  
by K6LHA on March 19, 2008 Mail this to a friend!
NI0C commented on March 19, 2008"

"AF6AY expressed concern "that heated-up anode is also going to produce wasted heat (largely in IR frequencies not the RF Hetzes going to the antenna)."

"Len, in tube amplifiers such as those using the 3-500Z, that wasted heat is actually pretty small compared to the energy sent to the antenna. Might as well use that heat energy to help extend the life of the tube."

Was I addressing the '3-500Z?' I don't think so. I was commenting on OLDER power amplifier tubes that I've tuned up, namely the 833 triode.
...........

"Check out the efficiency of an Ameritron AL-80B amplifer, for instance. As I recall, it is on the order of 70%."

You fix me up with a shield room and some more RF testing equipment and I will play 'ARRL Lab' in 'checking it out.' After I finish installing my SmallIR vertical in the back yard, that is. [see how easy it is to name-drop in these venues? lots of others do that, so I might as well do that, too! :-) ]

Late this afternoon I happened to be INSIDE the Burbank, CA, HRO (it's on Magnolia with abominable parking, not like the one they had a bit over a year ago in a mini-mall). I picked up one of their catalogs on exiting but I haven't memorized it cover to cover. Since I'm not interested in Being a radio station or having all that POWER on HF, I must have MISSED 'checking that one out.' Mea culpa. Mea culpa.

Is that Ameritron amp a LINEAR? If so, 'splain how it gets "70% efficiency." Good old Jimmy (N2EY) has always stated that ONLY Class-C amplifiers have that kind of efficiency. Class-C is definitely NOT 'linear.'

Hey, if efficiency is 70% and an amp is rated at 1000 Watts, then 30% or 300 Watts is WASTED as excess HEAT. <shrug> I don't have air conditioning specifically for my 'shack,' only the whole house. 300 Watts is more heat than is wasted by all of my small collection of amateur radio equipment sitting on the home office desk. [it is all solid-state]

I'm all for efficiency, but I'm not going to go nuts about the subject. Some in here LIVE for that kind of thing. :-)

Gee, isn't it just so much great fun poking at the 'newbies' for not following the 'leaders' and their Absolute Advice (AA) in here? :-) Sort of an amateur radio '12 step program.' :-)

73, Len AF6AY
 
RE: Plate Color Facts  
by W8JII on March 19, 2008 Mail this to a friend!
Interesting post Len. You're the one that by your own admisson stated you had limited qualifications concerning Glass hi power tubes. I stated the simple fact that Tom was infinitely more qualified than you on the subject. You then go on to question my qualifications. Len you have no idea what my qualifications are. You might be surprised.....73, Ron
 
RE: Plate Color Facts  
by K6LHA on March 19, 2008 Mail this to a friend!
W8JII tried to mix a reply potion on March 19, 2008:

"Interesting post Len. You're the one that by your own admisson stated you had limited qualifications concerning Glass hi power tubes."

At HF. :-) For DESIGN OF VACUUM TUBES. To make a quotable denigration more formidable for later use, I will admit NEVER DESIGNING A SINGLE VACUUM TUBE IN MY LIFE. There! That ought to be good for a put-down you can save for later on your hard disk. :-)

High-power tube CIRCUITS, YES, just NOT the TUBES THEMSELVES. :-)

BTW, how many vacuum tubes have YOU designed? :-)

"I stated the simple fact that Tom was infinitely more qualified than you on the subject."

'Infinitely?' Since I've never ever designed a vacuum tube, that MIGHT apply. So, how many vacuum tubes has N8JI designed and made? In NONE, then you are incorrect.

"You then go on to question my qualifications."

I didn't strap you down and do any water-boarding on you, did I? Considering I've been a professional in electronics (which concerns 'radio' since it is a subset of electronics) for 56 years, YES, I will question retired pharmacists on their electronics expertise in CIRCUIT AND SYSTEM DESIGN OF ELECTRONICS.
<shrug>

"Len you have no idea what my qualifications are. You might be surprised."

PLAGIARISM ALERT!

That's the sort of NULL reply that good old Jimmy (N2EY) uses, has used for a long time in 'discussion' venues about amateur radio. :-)

Says NOTHING, but IMPLIES a lot, most of which is plain old vaporware. Think of it as a placebo to ease the minds of test subjects in medication trials. :-)

If YOU have some qualification in any sort of circuit or system design, then please state them. Just don't try that old middle-school non-debate trick of IMPLICATION, okay. I'm not impressed by mere implication. I've got a resume' (somewhere, sitting in a drawer, don't need one anymore), corporate experience working for electronics firms, formal education in the subject...and years of working out design problems with hands-on experience. If you can top that, fine, but the old "you would be surprised at how much..." phrase doesn't cut it, doesn't come close.
:-)

Okay, so where is all the 'discussion' about VACUUM TUBES OTHER THAN POWER AMPLIFIERS? I still think vacuum tubes are nifty things for a lot of purposes. I still think that semiconductors, particularly ICs, are much niftier. I don't recall using ANY power tube (other than thyratrons and Nixies) which GLOWED. The only semiconductor that glowed red for me happened many years ago, accidentally, when a small zener got WAY too much in the way of electrons and positively GLOWED. But only briefly, then went totally open. :-)

Hey, there ya go! Another KEEPER for personal denigration use later on! I am so obliging!

Old tyme ham extras NEVER make mistakes. They just IMPLY their way all over the place. :-) Gotta love some of these venues...

73, Len AF6AY

 
RE: Plate Color Follies  
by NI0C on March 20, 2008 Mail this to a friend!
Addressing AF6AY's quibbling:

"Was I addressing the '3-500Z?' I don't think so. I was commenting on OLDER power amplifier tubes that I've tuned up, namely the 833 triode."


No, but W8JI was. He designed the AL-80B, which uses the 3-500Z tube that has the properties he described.



" "Check out the efficiency of an Ameritron AL-80B amplifer, for instance. As I recall, it is on the order of 70%."

You fix me up with a shield room and some more RF testing equipment and I will play 'ARRL Lab' in 'checking it out.' After I finish installing my SmallIR vertical in the back yard, that is. [see how easy it is to name-drop in these venues? lots of others do that, so I might as well do that, too! :-) ] "



I wasn't name dropping-- I merely cited an example I was familiar with-- the Ameritron AL-80B (I've owned one for ten years). And you really don't need a shield room to check out the efficiency-- just a good RF power meter to measure the output power, plus meters to measure the power line voltage and current.



"Since I'm not interested in Being a radio station or having all that POWER on HF, I must have MISSED 'checking that one out.' Mea culpa. Mea culpa."



The FCC allows the use of up to 1500 watts on most amateur bands. I'm not apologizing for employing roughly half the legal limit when conditions warrant it.


"Is that Ameritron amp a LINEAR? If so, 'splain how it gets "70% efficiency." Good old Jimmy (N2EY) has always stated that ONLY Class-C amplifiers have that kind of efficiency. Class-C is definitely NOT 'linear.'

Hey, if efficiency is 70% and an amp is rated at 1000 Watts, then 30% or 300 Watts is WASTED as excess HEAT. <shrug> I don't have air conditioning specifically for my 'shack,' only the whole house. 300 Watts is more heat than is wasted by all of my small collection of amateur radio equipment sitting on the home office desk. [it is all solid-state] "



According to the AL-80B manual, the 3-500Z tube is used in a class AB2 grounded grid ciruit, and the efficiency is approximately 65% (I said earlier "on the order of 70%.").

As far as heat goes, your calculations are close. Using the 65% number with 1KW output yields 538 watts of wasted power. But that's the peak power lost during transmission-- average power lost during transmitting would be about half that, or 270 watts; while during standby mode the amplifier only draws 1A from a 120V line (120 watts).



"Gee, isn't it just so much great fun poking at the 'newbies' for not following the 'leaders' and their Absolute Advice (AA) in here? :-) Sort of an amateur radio '12 step program.' :-)"



I certainly wasn't poking fun at you. I was merely emphasizing W8JI's point about certain vacuum tubes using plate dissipation to help improve the life of the seals in the tube, that's all.

If you wanted to get into a discussion comparing tube amplifiers versus solid-state amplifiers, we could do that. I would simply point out that tube amplifiers still have certain advantages over the solid-state-- namely, low cost and generally greater tolerance for output mismatches. The solid state amplifiers might be slightly more efficient in terms of heat loss.


73,
Chuck NI0C
 
RE: Plate Color Follies  
by W4LGH on March 20, 2008 Mail this to a friend!
If I recall correctly, I believe GE had the registered trademark on "Compactron". It was sort of the early day of "IC's" as far as tubes were concerned, meaning there were several tubes in one bottle. I believe the 6GF7 was a Compctron, that was used as the vert blanker, vert odc, and the vert output.

There arer people out there who have made their own tubes, a good example is on YouTube. Shows the entire process, then one tube in his receiver, and one in his transmitter. Pretty neat to watch his process from start to finish, and then see it work in a circuit.

73 de W4LGH - Alan
http://www,w4lgh.com
 
RE: Plate Color Facts  
by N2EY on March 20, 2008 Mail this to a friend!
NI0C writes:

"..but W8JI was. He designed the AL-80B, which uses the 3-500Z tube that has the properties he described."

W8JI has designed other amps as well, and is very knowledgeable on the subject. Look at his earlier posts in this thread - he is correct in every detail.

NI0C: "According to the AL-80B manual, the 3-500Z tube is used in a class AB2 grounded grid ciruit, and the efficiency is approximately 65% (I said earlier "on the order of 70%.")."

65% is theoretically possible in AB2. Class C amplifiers can do even better, (75%) but are not linear.

Comparable HF linear amplifiers using solid-state devices have not achieved that order of efficiency. They typically run about 50-55%. They also cost more.

NI0C: "Using the 65% number with 1KW output yields 538 watts of wasted power. But that's the peak power lost during transmission-- average power lost during transmitting would be about half that, or 270 watts; while during standby mode the amplifier only draws 1A from a 120V line (120 watts)."

So the actual heat dissipation, averaged over time, is about 130 watts (half the time transmitting, half the time receiving).

NI0C: "I was merely emphasizing W8JI's point about certain vacuum tubes using plate dissipation to help improve the life of the seals in the tube, that's all."

What actually happens is that tubes like the 3-500Z use high-temperature getter materials on the anode of the tube to keep a high vacuum. These materials, such as zirconium and tantalum, do not getter effectively at low temperatures. They are *designed* to operate
showing color, typically cherry-red.

This isn't a new thing. 833s have tantalum anodes for this very reason. 833As have zirconium-coated anodes for this reason too. They are designed to operate at up to orange-red color on the plate.

Those are the facts, which W8JI and others have correctly stated, and which are backed up by manufacturer's data.

NI0C: "If you wanted to get into a discussion comparing tube amplifiers versus solid-state amplifiers, we could do that. I would simply point out that tube amplifiers still have certain advantages over the solid-state-- namely, low cost and generally greater tolerance for output mismatches."

Correct on all counts.

NI0C: "The solid state amplifiers might be slightly more efficient in terms of heat loss."

Actually they are not. Look at any HF amateur transceiver with solidstate finals, and compute the DC input required to get 100 watts RF output. Typically it's about 18 amps at 13.8 volts - 248 watts.

73 de Jim, N2EY
 
RE: Solid State vs. Hollow State HF Linears &  
by N2EY on March 20, 2008 Mail this to a friend!
Here's a comparison of two current HF linear amplifiers for hams:

The Ameritron AL-80B uses a single 3-500ZG and is rated 1000 watts RF output. It can be powered by a 120 volt outlet (needs 15 A), so the maximum primary power requirement is 1800 W (15 A at 120 VAC) to produce 1000 W of usable RF output.

The Yaesu VL1000 is rated also 1000 watts RF output. It can be powered by a 120 volt outlet but can only run 500 W at that level. For the full 1000 W output, the VL1000 needs 240 V at 14 A, so the maximum primary power requirement is 3360 W to produce 1000 W of RF.

Part of this difference is the different efficiencies of the power supplies. However, the specifications say that the VL1000 amplifier requires 2100 watts input to produce 1000 W of usable RF output.

The VL1000 has no tuning controls and can be set up to automatically change bands, while the AL-80B requires manual band selection and tuneup of the output circuit.

Which amplifier do you think generates more "waste" heat in actual operation?

Universal Radio advertises the AL-80B at $1360. The VL1000 price is $4000.

It's great to have such choices.

73 de Jim, N2EY
 
RE: Plate Color Facts  
by K8MN on March 20, 2008 Mail this to a friend!
Len:
"You have a long habit of disagreeing with others (with some exception of other morsemen). Most folks would put you down as just plain disagreeable. <shrug>"

I submit that you have no idea of how most folks feel about me, Len. I don't know most folks and neither do you.

K8MN:
"W8JI gave you some information which you've chosen to ignore. He's an engineer with lots of high power linear amplifier design experience under his belt."


Len:
"You are NOT an engineer nor have you any experience in designing high power RF amplifiers (linear or non-linear)."

You're right in that I'm not an engineer. You're wrong about my never having designed any high power RF amps.
I assuredly have done so and continue to do so.

"You should not attempt chastising others' technical advice until you've advanced beyond just the collecting of old vacuum tubes."

You've had numerous experienced folks give you factual advice on the matter. They've quoted from manufacturers of high power tubes. You chose to get pissy and to argue.

Len:
"I AM an engineer in electronics design but have not worked with linear RF power amplifiers (only non-linear) and have not designed or manufactured any vacuum tubes. "

Well, there you go. You have limited experience in what is being discussed.

Len:
"As to "manufacturers making mistakes in their documentation," YES, SOMETIMES THEY DO. That is why 'errata' sheets are published and distributed as soon as a document is discovered to contain a mistake."

Surely if a mistake was made, the manufacturer would surely, after the material was published, have issued an errata sheet during a couple or three decades. When several manufacturers state the same thing and none have published errata sheets, that says Len Anderson is wrong.


Len"
"Live with that."

Oh, I think I could live with errata sheets, Len.
None have been issued contradicting what you've been told about color on the plates of high power transmitting tubes.

Len:
"I've had to for a half century in order to keep a paycheck coming regularly (unlike some government workers)."

Was your point that government workers aren't paid on a regular basis or that you had to live with errata sheets in order to be paid?

Len:
"You might want to check the TOC of QST sometime and take note of a-now-almost-regular occurrance of CORRECTIONS which may be 3 to 4 months old. [ARRL is a manufacturer of publications, not vacuum tubes or electronic hardware] Periodicals of the electronics trade ['controlled circulation' types one can get free if one is in the business] have the same problems. MISTAKES HAPPEN."

It's been decades since that data on high power transmitting tubes was published. Shouldn't the errata sheet have shown up by now? Now I sold Eimac and RCA high transmitting tubes to government, broadcasters, industry and radio amateurs for five or so years. I had a trunk full of catalogs, application notes and data sheets. You'd think that if Eimac or RCA made an error, we'd have gotten errata sheets or corrected publications. That didn't take place.


Len:
"Alan remarked 'Nothing in life works out as it is written in a textbook.' That is a METAPHORICAL statement, an observation, perhaps a satirical comment.

If it was such, it was wrong.

Len:
"I've been openly chastised in amateur radio forums (by yourself, certainly) for 'not doing things as I was supposed to do them.' [there's lots more in my human experience side, non-radio, but that isn't for this forum]:"

You've only had a year in which to be wrong in amateur radio, Len. So far, you're doing a pretty good job.

Len:
"The intended subject of this article forum was VACUUM TUBES. Now, it is a safe bet that FEW in here have ACTUALLY MADE THEIR OWN VACUUM TUBES or even MADE THEM AS MANUFACTURERS. I haven't."

I'm glad you refreshed my memory, Len. When we drifted off toward CMOS devices and such, I almost forgot.
So you haven't made tubes, have limited experience in using high power transmitting tubes and haven't sold them. That's good enough for me and it explains your lack of knowledge on the subject.

Len:
"...vacuum tubes are becoming OBSOLETE. They are used now only in niche applications in all of electronics."

We radio amateurs happen to be involved in one of those niche applications for high power transmitting tubes.
If vacuum tubes for high power RF amplifiers are becoming obsolete, why are they outselling solid state amps by a factor of about 9:1?

Len:
"To get into disagreeable internecine warfare - just for the sake of arguing (or proving what a great and glorious person one is) - certainly for dragging over old personality conflicts from other, previous venues - is nonsensical. It is 'counterproductive.'"

Then I'm darned if I can understand just why you are attempting to engage in such things. You put forth mistaken views. N2EY corrected you. W8JI corrected you. W8JII corrected you. I corrected you. Who's the guy showing a lack of self control and more than a little mulishness? It appears to be you.


Len:
"I've done very LITTLE design or building of vacuum tube circuits since around 1980, a period of just a bit over a quarter century."


Have you designed, built or regularly used high power transmitting tubes at all in that time?

Len:
"I KNOW - in general - how they work (including some that aren't used in US amateur radio) and all I can relate is some observations and actual, life experience in USING some high power vacuum tubes."

Let me run it down for you, Len: A number of folks here appear to have quite a bit of experience in building, designing, operating amplifiers using high power transmitting tubes. Some of 'em have quoted manufacturers data (on which no errata sheets were issued). You've still argued with them. What's the deal?

Len:
"Some in here are terribly offended by that (at least in words), trying to push some personal agenda of theirs. Why? Vacuum tubes are going away in electronics technology. It is inevitable. Yes, they launched PRACTICAL radio communications, no denying that, but that doesn't mean they will 'always be with us' or that we should devoutly revere their existance forever more."

Maybe you didn't understand. If something is still in wide use and is still manufactured and that something is more efficient than the "modern" way of doing it, that something isn't obsolete.

Dave K8MN
 
RE: Plate Color Follies  
by K6LHA on March 21, 2008 Mail this to a friend!
W4LGH posted on 20 Mar 08:

"If I recall correctly, I believe GE had the registered trademark on "Compactron". It was sort of the early day of "IC's" as far as tubes were concerned, meaning there were several tubes in one bottle. I believe the 6GF7 was a Compctron, that was used as the vert blanker, vert odc, and the vert output."

You might be right, but by the simple process of my posting anything to you will excite good old (youknowwho) into some sort of link-writing 'correction' flurry of postings. :-)

Those 'latter-day tubes' needed sockets with more pins than 9 (usually). Not a favorite of some designers of any sort of production electronics. I used one in an HV pulse output BVceo/BVcbo (Sat) test set module (Birtcher 10L) in the early 1960s...only because of the guaranteed voltage ratings and it being short enough to fit the plug-in module internal height. The 'dishpan' style (probably pioneered by Emerson in the mid-1950s) would take any sort of tube height so TV set designers didn't worry much about such dimension limits.
..........

"There arer people out there who have made their own tubes, a good example is on YouTube. Shows the entire process, then one tube in his receiver, and one in his transmitter. Pretty neat to watch his process from start to finish, and then see it work in a circuit."

Now THAT is interesting...actually MAKING one's own tubes. A bit too deep for what I would want to do as a hobbyist but (in my opinion) a shade MORE important than using already-made vacuum tubes (valves, ror, lampes).

Kind of ironic on where you say it was posted: YouTube. :-)

In private correspondence, Hans Summers has mentioned wanting to try his hand at making his own valves (G0UPL). Hans is a busy hobbyist concentrating on small QRP stuff, not afraid of trying out ANY technique.

Haven't looked there yet. Still have only dial-up over POTS. Wife and I are undecided on whether or not we will get one of the locally-available high-speed Internet services. There are several in this Los Angeles area where we live.

73, Len AF6AY
 
RE: Plate Color Follies  
by K6LHA on March 21, 2008 Mail this to a friend!
NI0C got his anodes hot and posted on 20 Mar 08:

"Addressing AF6AY's quibbling:"

[AF6AY] "Was I addressing the '3-500Z?' I don't think so. I was commenting on OLDER power amplifier tubes that I've tuned up, namely the 833 triode."

"No, but W8JI was. He designed the AL-80B, which uses the 3-500Z tube that has the properties he described."

OK, but I was NOT addressing the 3-500Z, so YOU are the quibbler. :-)
..............

"I wasn't name dropping-- I merely cited an example I was familiar with-- the Ameritron AL-80B (I've owned one for ten years). And you really don't need a shield room to check out the efficiency-- just a good RF power meter to measure the output power, plus meters to measure the power line voltage and current."

No dummy load? No controlled load impedance conditions? NOT good metrological practices, NI0C.

Well, I erred in NOT including a SCREEN ROOM. Mark me down as electronically 'spoiled,' always having a full SHIELD ROOM as my disposal. Mea culpa. True, a SCREEN or SHIELD room is not absolutely necessary but it is common industrial practice and insures that any outgoing RF stays IN the shielded area and that extermal RF stays OUT of the shielded area.

I realize that exhaulted RF designers (aka 'names') never ever emit stray RF, sort of like their waste products have no detectable odor. But having a shielded area to test in is still industry practice.
.............

"The FCC allows the use of up to 1500 watts on most amateur bands."

Now, now, don't get testy. Since I passed all my three tests on 25 Feb 07 (with 95% correct, 6 errors out of 120 total questions), I AM aquainted with FCC regulations in regard to the US amateur radio service. :-)

That sort of 'correction notice' is the kind of thing that good old Jimmy (N2EY) would post (and has many times elsewhere). :-)


"I'm not apologizing for employing roughly half the legal limit when conditions warrant it."

I've never implied otherwise. The FCC merely recommends using only as much power as is considered necessary to establish a radio contact. You were not spanked. Whatever floats your boat is fine by me. <shrug>
.............

"According to the AL-80B manual, the 3-500Z tube is used in a class AB2 grounded grid ciruit, and the efficiency is approximately 65% (I said earlier "on the order of 70%.")."

That's nice.

"As far as heat goes, your calculations are close. Using the 65% number with 1KW output yields 538 watts of wasted power. But that's the peak power lost during transmission-- average power lost during transmitting would be about half that, or 270 watts; while during standby mode the amplifier only draws 1A from a 120V line (120 watts)."

OK, 'my calculations are close' but something you wrote is 'on the order of...' and therefore 'better?' :-)

I'm not a big fan of 'efficiency' and was just tossing around a few items. Mostly to try to hook Miccolis...and I GOT him again! :-) It's almost too easy, but has become Grande Sport after a decade. :-)
.............

"I certainly wasn't poking fun at you."

Not directly, but I sense you were TRYING to do that. Many long-tymme amateur extras LOVE to do that. :-)

"I was merely emphasizing W8JI's point about certain vacuum tubes using plate dissipation to help improve the life of the seals in the tube, that's all."

Now, now, all readers can see what you were trying to say. No 'interpretation' or 'clarification statement' is necessary. :-)

It's fairly clear from reading most of these e-ham venues that Certain Names Are To Be Considered Foremost Authorities And Never Doubted. OK, are we 'ordinary folk' to be considered as serfs, vassals, and genuflect in their presence?

Where I come from in electronics, EVERYONE is fair game for commentary, 'Name' or no. I've been the one 'in the rack' for Design Reviews at work and also one of the 'torquemadas' turning the thumbscrews of 'victims.' It's all part of the SAME game in the workplace. Obviously it is NOT the 'same game' in amateur radio venues were Names and PR count more than honest appraisals of technical merit...and the Names have free rein on villifying those not respectful enough of their highnesses.

Hay, I made a personal comment on roughly one-third of the three dozen HF high power vacuum tube amplifiers used for HF communications a half century ago...where I was one of many (four shifts of operators) who QSYed each one at least twice in 24 hours. On a LIMITED number of tube types used then, where the anodes could be directly viewed, I observed NO discernable anode glow. Several 'Names' came on with 'I must be WRONG,' 'I must be mistaken,' 'I must be <fill in the blanks with other nastygrams>' and so forth. All these Names said that It Was A Good Thing, that glow. I questioned that 'good thing.'

I'm not sure EXACTLY sure what Eric was trying to say in starting this whole article, but I seriously doubt it was to be a knock-down, drag-out debate grande on POWER AMPLIFIERS. In my opinion, vacuum tubes are nifty things. They made modern radio PRACTICAL for communications. Also in my opinion, transistors and ICs and all solid-state stuff is NIFTIER than tubes. Those are my OPINIONS and personal, hands-on observations. If those disagree with opinions of Names and they sense a detraction of their exhaulted status, then TS. It's not my function in life to give them emotional sustenance. I'm just a HOBBYIST in an avocation that involves electronics...and one who began when the odor of heated selenium rectifiers was commonplace in 'radio.' [thanks be to God for creating those who created the silicon rectifier]

There's PLENTY of OTHER circuit applications for vacuum tubes other than POWER AMPLIFIERS.
Those would fit the original concept (?) of this article. And they would probably be more interesting to the general group of readers of this article. What has happened is the usual 'takeover' of a certain group who want to change the (apparent) intent to publicize their own pet things...anywhichwaytheycan. That too is my opinion. It is NOT up for debate.

73, Len AF6AY

 
RE: Plate Color Follies Cause Theater To Stay Open  
by K6LHA on March 21, 2008 Mail this to a friend!
N2EY wrote (for posterity purposes) on 20 Mar 08:

[NI0C]"..but W8JI was. He designed the AL-80B, which uses the 3-500Z tube that has the properties he described."

"W8JI has designed other amps as well, and is very knowledgeable on the subject. Look at his earlier posts in this thread - he is correct in every detail."

You have done a COMPLETE ('in every detail') design review of the AL-80B? What are YOUR qualifications? What have YOU designed in the way of high power vacuum tube amplifiers?

Yes, yes, 'we would be surprised at what you've done.' Yawn. Please omit the NULL replies you usually put forth.
..........

"65% is theoretically possible in AB2. Class C amplifiers can do even better, (75%) but are not linear."

Is it theoretically possible for good old Jimmy (N2EY) to have actually designed a vacuum tube high power RF amplifier? If he has, WHERE is it?

With all your emphasis on EFFICIENCY, exactly WHAT do you do with your efficiency SAVINGS?

How have you ACCURATELY MEASURED all of YOUR 'efficiencies'?
.............

"Comparable HF linear amplifiers using solid-state devices have not achieved that order of efficiency. They typically run about 50-55%. They also cost more."

Judging your statements made over the past decade, it would seem that anything for radio purposes costing more that $10 is way too much. :-) :-)

Keep checking those dumpsters. Maybe in ten years or so you can find an old solid-state HF power amplifier. Then you can 'convert' it to the 'more efficient' vacuum tube version. :-)
.............

"This isn't a new thing. 833s have tantalum anodes for this very reason. 833As have zirconium-coated anodes for this reason too. They are designed to operate at up to orange-red color on the plate."

Please tell us HOW MANY 833s (of any suffix) YOU have tuned up and observed (the anodes of) at around 1 KW RF output? For that matter, ANY high power tube amplifier at HF...
.............

"Those are the facts, which W8JI and others have correctly stated, and which are backed up by manufacturer's data."

Sunnuvagun! All along I thought the vacuum tube manufacturers had the data as the BASIS for designs and others (who actually, really designed) power amplifiers 'backed them up.' Thank you for giving us the straight skinny on the ORDER of things.

So, please tell us about YOUR experiences with getters in tube vacuums...like what kind of metalurgy techniques YOU use and the equipment with which you make all those tubes...and then what kind of tube life measurements you use. We can all benefit from such vast knowledge and direct experience with high power vacuum tube RF amplifiers.
.............

"Correct on all counts."

Well, there ya go! We have the WORD from another Foremost Authority.

:-)
 
RE: Plate Color Facts  
by K6LHA on March 21, 2008 Mail this to a friend!
K8MN got disagreeable on 21 Mar 08 and stated thusly:

"I submit that you have no idea of how most folks feel about me, Len."

Sensitivity to what others feel is a key item in cordial interaction with others.

<shrug> This article is NOT about social interaction with others, it is about VACUUM TUBES.

I personally think vacuum tubes are wonderful devices for electronics. I'm also of the opinion that solid-state devices are even more wonderful. <shrug>
...........

"You're right in that I'm not an engineer."

OHMYGAWD! Ring the bells, sound the trumpets! Davey actually AGREED that something I wrote was FACTUAL! [is this the start of your Reformation?]
...........

"You're wrong about my never having designed any high power RF amps.
I assuredly have done so and continue to do so."

Yes, I'm sure "I would be surprised at all the things you've done." [but never explained beyond generalities and ambiguous statements] :-)
...........

"You've had numerous experienced folks give you factual advice on the matter."

Long before anyone had any Internet access, I was getting FACTUAL DATA from both vacuum tube and semiconductor designers-manufacturers and applying those to a wide variety of circuit designs...both for a regular salary and for my own hobby pursuits.

Well before that I had worked regularly at a major Army HF communications station in operation of HIGH POWER HF transmitters. Long ago, yes, but the ONLY high power output stage active devices were vacuum tubes. Only two types of those 3 dozen (approximately, the number increased slightly in three years) transmitters had visible, observable anode structures: The 833 used in BC-339s and whatever was used in the Western Electric 4 KW PEP LD-T2 SSB (12 KHz bandwidth format). I did not note down the tube types in the Western Electric transmitters, either pre-WWII or post-WWII designs. I stated (correctly) that I did NOT observe any 'anode glow' in those observable-anode transmitters.

Now, being on duty for 8 hours a shift, 9 days of each 12-day cycle, gave me an opportunity to observe everything in that radio transmitting station for two years. Had there been ANY visible signs of anodes glowing, they WOULD have been noted and remembered. The ONLY case where 'anode glow' might have happened was in one transmitter (judged to have been improperly neutralized during a QSY but others of more knowledge and higher rank than I) to the point where the glass softened enough to break the vacuum. No one on that other shift had seen that 'anode glow' so I have no idea if it actually glowed. I have NO reason to exaggerate or otherwise embellish that observation...nor of my Army assignment (which I had absolutely no control over).

"You chose to get pissy and to argue."

Now, now, "is that anyway to talk to others?" :-)

Where did I 'disagree with all others' on this subject? I just don't agree with SOME of them wholeheartedly. Anywhere else that is not a treasonable offense. However, in here it IS if there is no wholehearted agreement with Names and the Foremost Authority Elite. <shrug>
............

"You have limited experience in what is being discussed."

Now, now, "is that anyway to talk to others?" :-)

Oh, my, "what is being discussed!" Yes, apparently the WHOLE article is about POWER AMPLIFIERS?!? Of course it is, the Names and the FA Elite have spoken.

I got the impression that Eric's original article subject was a 'salute' to ALL vacuum tubes, not just RF power amplifiers (for HF). I'll salute that.

I've worked IN the design of lots of different vacuum tube and semiconductor circuits since first achieving such design responsibility in 1960. It was NOT centered on HF power amplifiers or even products JUST for radio amateurs...just for the military, government, industrial, or consumer markets...including Research and Development projects in the mix. That's over four decades of you call 'limited experience.'

Hay, go honk yourself, Davey. You are being your general disagreeable self again, looking down your nose at all us 'inferiors' who can't possibly be as Good As You (think you are).
.............

"Maybe you didn't understand."

You Elitists seem to have great difficulty understanding the rest of us hobbyists. <shrug>
............

"If something is still in wide use and is still manufactured and that something is more efficient than the "modern" way of doing it, that something isn't obsolete."

Why don't we just rephrase your Pronouncement as: "If the Elite use something then it will never be obsolete (because it will always be The Best)." :-)
............

Wow, make one little observation about 'lack of anode glow' (in power amplifier tubes) and the nuclear piles of the Names and the Elite go critical! My Geiger counter is overwhelmed by all the radiation! :-)

"Tension, apprehension, and dissention have begun." - Alfred Bester in his novel "The Demolished Man."
 
RE: Plate Color Follies  
by K8MN on March 23, 2008 Mail this to a friend!
NI0C:
"As far as heat goes, your calculations are close. Using the 65% number with 1KW output yields 538 watts of wasted power. But that's the peak power lost during transmission-- average power lost during transmitting would be about half that, or 270 watts; while during standby mode the amplifier only draws 1A from a 120V line (120 watts)."

Len:
"I'm not a big fan of 'efficiency' and was just tossing around a few items. Mostly to try to hook Miccolis...and I GOT him again! :-) It's almost too easy, but has become Grande Sport after a decade. :-)"

You're not a fan of efficiency? That's a rather peculiar statement, Len, unless it was made in order to rationalize the fact that solid state amps aren't as efficient as vacuum tube amps.

This angling thing you have going--am I to understand that it consists of you posting inaccurate or non-factual information and that when someone corrects that erroneous information, he has somehow been 'caught' by you? I can't imagine that you derive pleasure by looking foolish.

NI0C:
"I certainly wasn't poking fun at you."

Len:
"Not directly, but I sense you were TRYING to do that. Many long-tymme amateur extras LOVE to do that. :-)"

There are reasons for that and you've been supplying a number of examples in this thread.

Len (on W8JI):
"It's fairly clear from reading most of these e-ham venues that Certain Names Are To Be Considered Foremost Authorities And Never Doubted. OK, are we 'ordinary folk' to be considered as serfs, vassals, and genuflect in their presence?"

Certain folks *are* authorities on a number of subjects. When someone who is an authority writes on one of those subjects and his statements are backed by hard data, it'd be rather foolish for someone who has limited experience so begin arguing from a position of ignorance. Nobody here referred to you as a serf or vassal or requested that you genuflect. That's part of a complex you've exhibited elsewhere. It long precedes your entry into amateur radio.

Len (further on W8JI):
"Where I come from in electronics, EVERYONE is fair game for commentary, 'Name' or no. I've been the one 'in the rack' for Design Reviews at work and also one of the 'torquemadas' turning the thumbscrews of 'victims.' It's all part of the SAME game in the workplace."

This isn't the workplace and you aren't on a design team here, Len. W8JI has decades of experience in designing high power RF amps. You aren't his rater or reviewer. You can play at being Torquemada, but don't expect folks to welcome those actions.

Len (yet more on W8JI):
"Obviously it is NOT the 'same game' in amateur radio venues were Names and PR count more than honest appraisals of technical merit...and the Names have free rein on villifying those not respectful enough of their highnesses."

Perhaps you've missed it: Tom has been around for a long time. His expertise is well known. You've not been vilified, though I could understand after reading your insulting posts, why you might be. Long time radio amateurs (those who've been in the game for longer than a year) might take exception to your manner or style.

Len:
"Hay, I made a personal comment on roughly one-third of the three dozen HF high power vacuum tube amplifiers used for HF communications a half century ago...where I was one of many (four shifts of operators) who QSYed each one at least twice in 24 hours. On a LIMITED number of tube types used then, where the anodes could be directly viewed, I observed NO discernable anode glow. Several 'Names' came on with 'I must be WRONG,' 'I must be mistaken,' 'I must be <fill in the blanks with other nastygrams>' and so forth. All these Names said that It Was A Good Thing, that glow. I questioned that 'good thing.'"

I was one who suggested that you might not remember, after half a century, whether the tubes' plates were glowing or not. If you're quite certain that they weren't, then they weren't being run very hard.

You did more than "question", Len. You became abusive and argued the point long after documentation supporting the statements of others, was produced.


Len:
"I'm not sure EXACTLY sure what Eric was trying to say in starting this whole article, but I seriously doubt it was to be a knock-down, drag-out debate grande on POWER AMPLIFIERS."

You instigated the knock down, drag out portion of the debate.

Len:
"In my opinion, vacuum tubes are nifty things. They made modern radio PRACTICAL for communications. Also in my opinion, transistors and ICs and all solid-state stuff is NIFTIER than tubes."

Fine, Len. Why not save that stuff for a thread concerning transistors and IC's?

Len:
"Those are my OPINIONS and personal, hands-on observations. If those disagree with opinions of Names and they sense a detraction of their exhaulted status, then TS."

You see, Len, there's your typical response to the views of others. You have a problem which lies deeper than your relative lack of knowledge concerning high power transmitting tubes.

Len:
"It's not my function in life to give them emotional sustenance. I'm just a HOBBYIST in an avocation that involves electronics...and one who began when the odor of heated selenium rectifiers was commonplace in 'radio.' [thanks be to God for creating those who created the silicon rectifier]"

What is your function in life, Len? Is it to be insulting toward others? Is it to try to make it appear that you know more than any mere radio amateur?

Len:
"There's PLENTY of OTHER circuit applications for vacuum tubes other than POWER AMPLIFIERS.
Those would fit the original concept (?) of this article. And they would probably be more interesting to the general group of readers of this article."

Nothing on God's green Earth has prevented you from posting something concerning those other vacuum tube circuits in this thread. What you've chosen to do is to become insulting with a number of people who seem to know a good bit more about transmitting tubes than you.

Len:
"What has happened is the usual 'takeover' of a certain group who want to change the (apparent) intent to publicize their own pet things...anywhichwaytheycan. That too is my opinion. It is NOT up for debate."

Like it or not, Leonard, *all* of your opinions are up for debate. Your opinions on the discussion above, were not well documented.

Dave K8MN

73, Len AF6AY
 
RE: Plate Color Follies Cause Theater To Stay Open  
by K8MN on March 23, 2008 Mail this to a friend!
N2EY:
"W8JI has designed other amps as well, and is very knowledgeable on the subject. Look at his earlier posts in this thread - he is correct in every detail."

Len:
"You have done a COMPLETE ('in every detail') design review of the AL-80B?"

I don't see where W8JI issued statements here regarding the design of the AL-80B.

Len:
"What are YOUR qualifications? What have YOU designed in the way of high power vacuum tube amplifiers?"

N2EY is a degreed electrical engineer.

Len:
"Yes, yes, 'we would be surprised at what you've done.' Yawn. Please omit the NULL replies you usually put forth."

There's your insulting behavior again, Len.

N2EY:
"65% is theoretically possible in AB2. Class C amplifiers can do even better, (75%) but are not linear."

Len:
"Is it theoretically possible for good old Jimmy (N2EY) to have actually designed a vacuum tube high power RF amplifier? If he has, WHERE is it?"

Why are you so insulting, Len? Has old Lenny designed or built (by himself) such an amp? If so, where is it?
Is old Lenny a degreed electrical engineer?

[more insults from Leonard snipped]

N2EY:
"Those are the facts, which W8JI and others have correctly stated, and which are backed up by manufacturer's data."

Len:
"So, please tell us about YOUR experiences with getters in tube vacuums...like what kind of metalurgy techniques YOU use and the equipment with which you make all those tubes...and then what kind of tube life measurements you use. We can all benefit from such vast knowledge and direct experience with high power vacuum tube RF amplifiers."

Jim didn't claim to have made vacuum tubes. You've previously stated that you haven't made vacuum tubes.
How would Jim's making of a vacuum tube relate to your erroneous position on gettering in high power transmitting tubes? You certainly appear to be a candidate for learning from Jim and Tom. You'd first need to turn off your transmitter and turn on the receiver, old timer.

Len:
Well, there ya go! We have the WORD from another Foremost Authority."

Well, you got accurate information from another someone whose knowledge of the topic exceeds your own.

Dave K8MN
 
RE: Plate Color Facts  
by K8MN on March 23, 2008 Mail this to a friend!
K8MN:
"I submit that you have no idea of how most folks feel about me, Len."

Len:
"Sensitivity to what others feel is a key item in cordial interaction with others."

That appears to be something of a 'do as I say, not as I do' predicament for you, Len.


Len:
"<shrug> This article is NOT about social interaction with others, it is about VACUUM TUBES."

Then why did you feel it pertinent to the discussion to introduce the topic of how others feel about me?

Len:
"I personally think vacuum tubes are wonderful devices for electronics. I'm also of the opinion that solid-state devices are even more wonderful. <shrug>"

You're free to write an article on solid state devices and to start a new thread concerning those devices.

K8MN:
"You're right in that I'm not an engineer."

Len:
"OHMYGAWD! Ring the bells, sound the trumpets! Davey actually AGREED that something I wrote was FACTUAL! [is this the start of your Reformation?]"

I wouldn't count on it being some sort of renaissance, Len. After all, I've never claimed to be an electrical engineer. Are you a degreed engineer and would that alone be enough to overcome erroneous information you've supplied here?

K8MN:
"You're wrong about my never having designed any high power RF amps.
I assuredly have done so and continue to do so."

Len:
"Yes, I'm sure 'I would be surprised at all the things you've done.' [but never explained beyond generalities and ambiguous statements] :-)

You've not put forth any books, manuals, web sites or other documentation for your incorrect stance on the gettering of high power transmitting tubes. In other words, you've never explained beyond generalization and ambiguous statements. :-)

K8MN
"You've had numerous experienced folks give you factual advice on the matter."

Len:
"Long before anyone had any Internet access, I was getting FACTUAL DATA from both vacuum tube and semiconductor designers-manufacturers and applying those to a wide variety of circuit designs...both for a regular salary and for my own hobby pursuits."

Whaddya know! We were both able to do that. I guess Jim and Tom and anyone else working in electronics and involved in amateur radio got their information the same way.

Len:
"Well before that I had worked regularly at a major Army HF communications station in operation of HIGH POWER HF transmitters...I stated (correctly) that I did NOT observe any 'anode glow' in those observable-anode transmitters."

Fine, Len. You've put forth your views on the situation as you remember it. If that's the case, the tubes were not being run very hard--not anywhere near their CCS or ICAS max.

Len:
"Had there been ANY visible signs of anodes glowing, they WOULD have been noted and remembered..."

They might have been noted; they might have been remembered. They might have been neither.

K8MN
"You chose to get pissy and to argue."

Len:
"Now, now, "is that anyway to talk to others?" :-)"

It was an accurate observation of your behavior here.

Len:
"Where did I 'disagree with all others' on this subject? I just don't agree with SOME of them wholeheartedly..."

It is interesting that those you disagreed with were the only people with accurate information. The one fellow you agreed with was in error.

K8MN:
"You have limited experience in what is being discussed."

Len:
"Now, now, "is that anyway to talk to others?" :-)"

You've admitted to such and your views indicate your lack of experience.

Len:
"Oh, my, "what is being discussed!" Yes, apparently the WHOLE article is about POWER AMPLIFIERS?!? Of course it is, the Names and the FA Elite have spoken."

Yes, Len, the discussion was about power amplifies. It is in that area that you began to be pissy and insulting while setting forth your erroneous views.

Len:
"I got the impression that Eric's original article subject was a 'salute' to ALL vacuum tubes, not just RF power amplifiers (for HF). I'll salute that."

Other vacuum tubes were discussed here. The differences in gettering techniques was brought up.

Len:
"I've worked IN the design of lots of different vacuum tube and semiconductor circuits since first achieving such design responsibility in 1960. It was NOT centered on HF power amplifiers or even products JUST for radio amateurs...just for the military, government, industrial, or consumer markets...including Research and Development projects in the mix. That's over four decades of you call 'limited experience.'"

That's wonderful for you, Len. That it was "NOT centered on HF power amplifiers" is evident. That didn't stop you from arguing about something on which you appear to have been ignorant.

Len:
"Hay, go honk yourself, Davey. You are being your general disagreeable self again, looking down your nose at all us 'inferiors' who can't possibly be as Good As You (think you are)."

I think you need to take a good, hard look at who is being disagreeable, Leonard. I made no comments regarding about how good you are. My comments addressed something which you didn't know. You should have a feeling of accomplishment now. You know something which you didn't know just a few days ago.

K8MN
"If something is still in wide use and is still manufactured and that something is more efficient than the "modern" way of doing it, that something isn't obsolete."


Len:
"Why don't we just rephrase your Pronouncement as: 'If the Elite use something then it will never be obsolete (because it will always be The Best).' :-)"

Because that wouldn't be what I intended to convey.
If that's your view, express it as such. Don't attempt to attribute it to me.


Len:
"Wow, make one little observation about 'lack of anode glow' (in power amplifier tubes) and the nuclear piles of the Names and the Elite go critical! My Geiger counter is overwhelmed by all the radiation! :-)"

Except that you made more than one little incorrect observation and you threw in some unpleasant attitude which you continue to exhibit. Maybe you'll figure it out someday.

Len:
"'Tension, apprehension, and dissention have begun.' - Alfred Bester in his novel 'The Demolished Man'."

In this situation, you created the tension, must have felt the apprehension and initiated the dissent.
I have no trouble in believing that you're feeling a little demolished, man.

Dave K8MN
 
RE: Plate Color Facts  
by NI0C on March 24, 2008 Mail this to a friend!
A couple of months after I received my degree in electrical engineering, I learned the most important lesson of my career.

That lesson was, simply, that I could learn from anyone-- that everyone has something to teach me if I only look hard enough for it.

So Len, I just wonder why you can't just say thanks for the lesson you learned here regarding tube anodes running red hot instead of throwing up walls of words at people in this forum.

73,
Chuck NI0C
 
RE: Plate Color Facts  
by K6LHA on March 24, 2008 Mail this to a friend!
NI0C lectured on 24 Mar 08:

"A couple of months after I received my degree in electrical engineering, I learned the most important lesson of my career."

"That lesson was, simply, that I could learn from anyone-- that everyone has something to teach me if I only look hard enough for it."

Yes, I'm sure that is true since I DO exist with that implicit dictum. But, I've only had electronic engineering design responsibility since about 1960 and then only in work for commercial or government projects, not that of amateur radio products. My degree came much later, well after I'd already done successful design tasks.

NI0C: "So Len, I just wonder why you can't just say thanks for the lesson you learned here regarding tube anodes running red hot instead of throwing up walls of words at people in this forum."

I just wonder why You cannot accept My words? My total comments were on only two types of power vacuum tubes, an 833 (of forgotten suffix) in a 1 KW HF CW transmitter and a forgotten power RF tube in a WE LD-T2 driver and final running 4 KW PEP on HF. Those were the only types that had visible anodes among the 36 to 41 transmitters at ADA transmitter site in years 1953 to 1956. Had I seen any anodes running with visible red glow, I would have noted that in memory and reported same. I do not recall any such conditions nor do approximately 400 color slides I took of that Signal Corps installation show any glowing anodes. Obviously the number of power amplifier tubes were limited in number and it was long ago. Eastman Kodachrome doesn't lie even if its emulsion suffers reticulation over a half century of storage.

All throughout my professional and avocational life I've tried to operate active devices according to manufacturer's specifications. Other than display tubes and thyratrons (which do glow) I've not used any power vacuum tubes that were of the type mentioned in the 'wall of words' put up by those demanding I apologize and accept (carte blanche) any statements from Foremost Authorities other than ACTUAL PA designers. [said FAs not being able to describe Their 'designs' in any specifics, only as "we would be surprised at what they've done" :-) ]

What you've got to understand is that Miccolis and Heil (N2EY and K8MN) both have some personal conflict with anyone who has argued or disputed their statements on other venues, principally on newsgroup rec.radio.amateur.policy for over eight years. That was, in the main, on the 'Code War' being waged between 1993 and 2007 regarding the US amateur radio morse code test elimination or retention for any US amateur radio license. Both of those have been (to put it mildly) militant about their pro-code-test opinions and have not hestitated to put down or demean the persons who took an anti-code-test position. That includes my voluntary US Army military service of '52-'56...and also the USAF career of one Brian Burke, then and still a US amateur radio licensee (N0IMD), plus others. All of that is archived now on Google and can be observed by anyone who wishes to look through hundreds of pages of posted messages. They are both doing here what they've done in the past on RRAP.

At this point in Eric's article life, I'm assured that the 'regulars' here think this is ONLY about power amplifier vacuum tubes and no other types of vacuum tubes. Further, the 'authorities' seem (I say conditionally) SEEM to demand all kinds of thanks for their information. Problem is that it does NOT seem to be reciprocal. I got INTO electronics when vacuum tubes were the only practical active devices available. I appreciate them. However, others seem to become very upset at not praising their glorious qualities. They get upset when I mention solid-state counterparts and think that I 'hate' tubes. Not so.

In my practical viewpoint on electronics engineering and operation, the 'thanks' one gets is operation of the equipment as designed. Anything more is quibbling over emotions of others. Way back in time a (then) old-timer in radio (pro and amateur) made a statement that I will always remember: "Electrons, fields, and waves operate by their laws, unaffected by human pleas, entreaties, or cuss words." I might add to the latter only the claims of certain Foremost Authorities who have not designed/engineered any products for sale to the amateur radio market. :-)

Try to keep a balanced outlook on things, old-timer...and a sense of humor.

73, Len AF6AY

 
RE: Plate Color Facts  
by K6LHA on March 24, 2008 Mail this to a friend!
Correction on my previous posting: The 'Code War' existed from 1998 (via NPRM 98-143) to December 2006 when the FCC released the Memorandum Report and Order defining the elimination of code testing on 23 February 2007. Mea culpa.

The 'Code War' had existed prior to 1990 but did not heat up until NPRM 98-143 was released.

833s existed prior to 1953. :-)

73, Len AF6AY
 
RE: Plate Color Facts  
by K8MN on March 26, 2008 Mail this to a friend!
NI0C lectured on 24 Mar 08:

Len:
"Yes, I'm sure that is true since I DO exist with that implicit dictum. But, I've only had electronic engineering design responsibility since about 1960 and then only in work for commercial or government projects, not that of amateur radio products. My degree came much later, well after I'd already done successful design tasks."

You do have a degree in electrical engineering, Len?

NI0C: "So Len, I just wonder why you can't just say thanks for the lesson you learned here regarding tube anodes running red hot instead of throwing up walls of words at people in this forum."

Len:
"I just wonder why You cannot accept My words? My total comments were on only two types of power vacuum tubes, an 833 (of forgotten suffix) in a 1 KW HF CW transmitter and a forgotten power RF tube in a WE LD-T2 driver and final running 4 KW PEP on HF. Those were the only types that had visible anodes among the 36 to 41 transmitters at ADA transmitter site in years 1953 to 1956. Had I seen any anodes running with visible red glow, I would have noted that in memory and reported same. I do not recall any such conditions nor do approximately 400 color slides I took of that Signal Corps installation show any glowing anodes. Obviously the number of power amplifier tubes were limited in number and it was long ago. Eastman Kodachrome doesn't lie even if its emulsion suffers reticulation over a half century of storage."

So what about your comments regarding gettering in high power transmitting tubes? Were those just throw away lines? What about the insulting behavior directed toward W8JI, N2EY, NI0C and myself? Were those throw away lines and not something related to your being corrected on your mistaken ideas?

Len:
"All throughout my professional and avocational life I've tried to operate active devices according to manufacturer's specifications."

So what you wrote about manufacturers making mistakes and issuing errata sheets, even when no such sheets were issued after some decades--that's just throw away stuff too?

Len:
"Other than display tubes and thyratrons (which do glow) I've not used any power vacuum tubes that were of the type mentioned in the 'wall of words' put up by those demanding I apologize and accept (carte blanche) any statements from Foremost Authorities other than ACTUAL PA designers. [said FAs not being able to describe Their 'designs' in any specifics, only as "we would be surprised at what they've done" :-) ]"

Well, you could have done a little research there at the home technical library you've spoken of. You could have done the same on the internet. You could have taken the word of Tom Rauch W8JI, but you didn't seem to know who he was. Apparently, you were so deep in your rant that it was too late for you to back out gracefully.

Len:
"What you've got to understand is that Miccolis and Heil (N2EY and K8MN) both have some personal conflict with anyone who has argued or disputed their statements on other venues, principally on newsgroup rec.radio.amateur.policy for over eight years."

That's both a falsehood ("with anyone who has argued...") and irrelevant to the discussion at hand.
If you're wrong about something, you're wrong.
Admit it and go on about your life.

Len:
"That was, in the main, on the 'Code War' being waged between 1993 and 2007 regarding the US amateur radio morse code test elimination or retention for any US amateur radio license. Both of those have been (to put it mildly) militant about their pro-code-test opinions and have not hestitated to put down or demean the persons who took an anti-code-test position."

I don't believe I ever heard of your prior to late 1996 or early 1997, Len. Again, the matter is irrelevant to the discussion at hand, but if you're going to bring it up, why not discuss your tactics? Were you militant?
Have you ever demeaned anyone? You know this is a trick question because you began doing it here in this discussion.

Len:
"That includes my voluntary US Army military service of '52-'56...and also the USAF career of one Brian Burke, then and still a US amateur radio licensee (N0IMD), plus others. All of that is archived now on Google and can be observed by anyone who wishes to look through hundreds of pages of posted messages. They are both doing here what they've done in the past on RRAP."

Again, Leonard, that stuff is irrelevant to this discussion, but since you've brought it up, what was said about your Army service? What have you said about military service and N2EY? What have you written about my military service and State Department employment?

Len:
"At this point in Eric's article life, I'm assured that the 'regulars' here think this is ONLY about power amplifier vacuum tubes and no other types of vacuum tubes."

It is your view that no one here can read an article and following the ensuing discussion thread?

Len:
"Further, the 'authorities' seem (I say conditionally) SEEM to demand all kinds of thanks for their information. Problem is that it does NOT seem to be reciprocal."

Where did such a demand "seem" to have been made, Len?
Who exactly "seemed" to ask for thanks? Why did you think that thanks was owed you, and for what?

Len:
"I got INTO electronics when vacuum tubes were the only practical active devices available. I appreciate them. However, others seem to become very upset at not praising their glorious qualities."

I don't give a whit whether you praise vacuum tubes or not. Just don't put forth erroneous information on the gettering of high power transmitting tubes. If you don't know something, why not ask questions or keep mum until you find out a bit about it?

Len:
"They get upset when I mention solid-state counterparts and think that I 'hate' tubes. Not so."

The thread is not about solid state devices, Len. If you'd like to discuss them, post an article. Have at it. I don't care whether you like vacuum tubes, just that you post accurate information.

Len:
"In my practical viewpoint on electronics engineering and operation, the 'thanks' one gets is operation of the equipment as designed."

That's rather odd. I think most engineers get their thanks in the form of a paycheck.

Len:
"Anything more is quibbling over emotions of others."

Then why are you quibbling? You've already been told how the gettering is done in high power tubes. Be happy that someone runs 'em as designed.

Len:
"Way back in time a (then) old-timer in radio (pro and amateur) made a statement that I will always remember: "Electrons, fields, and waves operate by their laws, unaffected by human pleas, entreaties, or cuss words." I might add to the latter only the claims of certain Foremost Authorities who have not designed/engineered any products for sale to the amateur radio market. :-)"

That's make a really swell tale when you design/engineer products for the amateur radio market.
In the mean time, you've taken issue with one fellow here who has a long history in the design/engineering of products sold in the amateur radio market. He and a number of others posting here know a good bit more about what was being discussed than you.

Len:
"Try to keep a balanced outlook on things, old-timer...and a sense of humor."

Why not make that your personal credo, Leonard?
You could paste it at the top of your computer monitor.

Dave K8MN


 
RE: K8MN's Anodes Constantly Running Red-Hot :-)  
by K6LHA on March 28, 2008 Mail this to a friend!
Sigh...the denigrations, denunciations, and demeaning accusations from K8MN go on and on and on for years...anywhere I post...:-(

It is unfortunate that the 'discussions' have concentrated on RF power amplifiers made from vacuum tubes. There are, and have been, a number of clever, noteworthy, innovating vacuum tube designs produced for all sorts of circuit applications in the past 7 or so decades. Those COULD have been subjects of enlightening discussion that combines the high nostalgia content of old-timers' recollections and the constantly advancing technology of electronics. That (unfortunately) did not happen. Instead, there has been the usual "I am your leader" kind of boasting coupled with some sort of "need" to honor-respect-revere a very very few who have produced amateur radio products in certain applications relative to radio, not to mention the back-biting of those with long-running personality conflicts that conflictors cannot shake off.

For myself, I present no apologies for what I've written so far in this article. I do not have a lifetime of experience with ham radio...but, I DO have all of my adult lifetime as experience in professional electronics and radio that BEGAN with high-power HF transmitters on a larger scale than nearly all (publicized) radio hams have done. A very few in here (most notably K8MN) are openly resentful of that. In truth, I had absolutely no control of where I was assigned in my voluntary military service. I DID have control over doing the best service I could and learned much about HF communications around the world in the 1950s. Many of those techniques of communications of the 1950s are still being done by radio amateurs, some of which insist and insist that the OLD ways are the "best" ways.

In the last 6 decades of radio's existance, there have been multiple plateau-leaps of technological advancement. I've witnessed those and marvel at the expansion of modes and modulations and ways to perform new functions in a much smaller space with much less power demand of operating. Many in here do not seem to appreciate those advancements and prefer to overly emphasize all those old methods as the 'only' way to do things and constantly venerate all those old ways. Indeed, a few of the latter have become obsessed with only those old ways that, not coincidentally, where how They began so long ago. I would rather celebrate the present and look forward to the next developments which are sure to be improvements over what exists now.

Vacuum tubes made radio PRACTICAL. That should be a wonder in itself. But, it is not the 'end' of technology nor a limitation on possible improvements.
Instead, in here, we've all been subjected to 'the usual' personality conflicts where there exists some sort of virtual 'battle' for warlordship by some.

Amateur radio remains a hobby pursuit, a personal avocation (without monetary compensation) out of a personal interest in radio communications. It isn't a political arena nor is there any General Election where one and only one will 'win national leadership' on the basis of emotions. Nor is this forum some sort of 'judgement at Nuremberg' where self-styled torment-driven 'prosecuters' wish to have certain hobbyists banned, hanged, and otherwise kept out of sight.

If one's RF power amplifier plates glow red...and that is stated on the tube manufacturers' data, then fine. But, NOT ALL RF power amplifier plates exhibit such a glow. Some have NO visible plate structures. To get totally bent out of shape that anyone objects to visible red-hot anodes is rather immature to my mind. That sort of conflict openly expressed is more indicative of OTHER things, not any cause for Word War over amateur radio technology.

AF6AY
 
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