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eHam Forums => Amplifiers => Topic started by: AG6K on October 22, 2011, 04:28:30 PM



Title: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 22, 2011, 04:28:30 PM
Background radiation came to my attention after a friend in Ojai gave me a Geiger counter.  When I was on 40m in the daytime chatting with friends I'd turn it on to see what was going on in the background in this corner of the universe.  My 1959 high-school graduation wrist-watch with a glow in the dark radium dial was a good source source of radiation.   Most of the time the Geiger counter would indicate a low count but occasionally there would be a burst that would send the count soaring.   Later I read that our sun emits x-rays and gamma-rays - plus supernovas emit large bursts of gamma-rays and that there about 60 supernovas per year.
  A Geiger-tube is basically a gas-filled chamber with HV on two electrodes with not quite enough volts on them to ionize the gas and cause conduction.  Thus, when an x-ray or gamma ray photon sails through the Geiger tube and strikes a gas atom, it can add enough extra energy to knock an electron loose, thereby causing conduction - which is then counted on the digital display.   This started me wondering whether or not an x-ray of gamma-ray photon could knock an electron loose inside a 3-500Z or 572B and cause conduction to take place? 
  Does this sound reasonable or not reasonable?  tnx
Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: N6JP on October 22, 2011, 06:42:46 PM
Well I don't know about affecting a tube, but I remember various families of digital logic being sold way back in the late 60's and 70's that were radiation hardened for use in outer space.  A ordinary logic chip was subject to all sorts of problems when it was bombarded by radiation.  They would change logic states and such, and crash computers and/or the devices they were installed inside. 

I remember an ordinary TTL chip that costs around  .25 cents ran around 5-10 bucks if it were radiation hardened.  Unbelievable the extra cost involved to harden the logic chips.  I can only imagine what it could do to a tube being used in a critical application.  I'm not sure how one would harden a tube?

Jer n6jp


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: W8JI on October 22, 2011, 07:56:41 PM
.   This started me wondering whether or not an x-ray of gamma-ray photon could knock an electron loose inside a 3-500Z or 572B and cause conduction to take place? 
  Does this sound reasonable or not reasonable?  tnx
Rich, ag6k

Years ago I remember reading your proposals, where horrible arcs were started by a photon or gamma ray striking a tube biased-off on standby, and the gamma burst making the antenna relay arc when the tube was thrown violently into conduction by the x-ray.

I often think of your photon-bombardment-causing-relay-contact-arc and catastrophic HV failure theory when I turn the light on in my family room. I keep waiting for the neon bulb near the dog food bowl to explode, and kill an innocent puppy with shards of glass or molten metal, but nothing happens. :-)

That's really a very bizarre theory, that even argues against itself. For the tube to avalanche, it would have to be worse than a Geiger tube. It would have to be worse than a neon bulb.  I wouldn't spend much money shielding a tube that gassy from photons, unless it was in the warp drives on the USS Enterprise.

I also shine flashlights in my amplifiers on the tubes, and so far none have blown up.

73 Tom


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 22, 2011, 10:12:04 PM
Quote
Well I don't know about affecting a tube, but I remember various families of digital logic being sold way back in the late 60's and 70's that were radiation hardened for use in outer space.  A ordinary logic chip was subject to all sorts of problems when it was bombarded by radiation.  They would change logic states and such, and crash computers and/or the devices they were installed inside.

I remember an ordinary TTL chip that costs around  .25 cents ran around 5-10 bucks if it were radiation hardened.  Unbelievable the extra cost involved to harden the logic chips.  I can only imagine what it could do to a tube being used in a critical application.  I'm not sure how one would harden a tube?

Jer n6jp

  Interesting Jer.  I have motion detectors on this property and sometimes they go off when there's nothing coming up the driveway.  Perhaps it's an errant photon from who knows where ?   Since gamma-rays can penetrate lead, I don't think there's a practical way to keep them out.  Probably the best way to protect a tube from damage is a glitch-R to limit peak discharge-I from the filter C?
Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: N3JBH on October 22, 2011, 10:23:09 PM
Actually Tom your statement is bizarre, There would not be shards of glass or molten metal from the neon bulb. that is just plain silliness on your part speaking there. The heat generated by the neon gases would cause a rapid instantaneous combustion that actually send molten glass  to be expelled from the bulb with both the force and destructive power of a high powered shape charge, Oh the poor puppy  :(   Jeff


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: KB4QAA on October 23, 2011, 04:14:18 AM
There is a semi formal paper that was published fifteen or twenty years ago discussing cosmic radiation and its effect on semiconductors in personal computers.  It provided estimates of the chance of an individual being affected.   The numbers were small, but possible.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: G3RZP on October 23, 2011, 05:26:00 AM
Quite a lot has been published about semi conductors and radiation. The effects are very dependent on the process and the geometry: at Plessey Semiconductors, we had some logarithmic amplifier ICs in a bipolar process. These were irradiated to such an extent the white alumina substrate turned brown, and yet the change in performance of the three dual amplifier chips couldn't be measured.

But considering the vast number of vacuum tubes of one sort or another - TWTs, magnetrons, klystrodes as well as 'conventional' transmitting tubes in daily use, if it was an effect, it would appear far more frequently than the odd flashover.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: KA5N on October 23, 2011, 05:28:55 AM
I think it is all due to etherial drift which seems to have veered this Forum off course in
recent weeks.  I can't wait until it gets back on track.

Allen


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: M0HCN on October 23, 2011, 08:51:15 AM
The GM tubes have a ***very*** fine wire used for the anode, so there is a very high electric field in the vicinity.

Thus an electron released at the cathode by the photoelectric effect or just a beta wondering into the tube at low energy will have a high probability of being accelerated to an energy sufficient to trigger an avalanche in the tube. Incidentally this is why GM tubes are poor for spectrographic studies, the pulse height is largely independent of the energy of the particle.

A 3-500Z or whatever by contrast has a heated cathode that runs (normally) in a permanent cloud of electrons, with the grid screening them from reaching the anode. There is nothing like the electric field strength and nothing like enough gas (except in some modern tubes :( ) to cause avalanche breakdown. 

Consider a electron being knocked off the grid by a cosmic ray, well given the grid capacitance and the size of the charge on the electron you can work out the change in voltage on the grid (hint is is small). The same applies to an electron knocked off a gas molecule as long as there is insufficient gas and electric field strength to cause an avalanche discharge (Which is a tube design consideration).

Tube breakdown in a sufficiently gassy tube might be triggered by a cosmic ray I suppose, but realistically that tube would fail in short order anyway if it is that gassy..
 
I don't really buy it as a significant effect.

Regards, Dan.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 23, 2011, 09:01:50 AM
Quote
Years ago I remember reading your proposals, where horrible arcs were started by a photon or gamma ray striking a tube biased-off on standby, and the gamma burst making the antenna relay arc when the tube was thrown violently into conduction by the x-ray.

I often think of your photon-bombardment-causing-relay-contact-arc and catastrophic HV failure theory when I turn the light on in my family room. I keep waiting for the neon bulb near the dog food bowl to explode, and kill an innocent puppy with shards of glass or molten metal, but nothing happens. :-)

That's really a very bizarre theory, that even argues against itself. For the tube to avalanche, it would have to be worse than a Geiger tube. It would have to be worse than a neon bulb.  I wouldn't spend much money shielding a tube that gassy from photons, unless it was in the warp drives on the USS Enterprise.

I also shine flashlights in my amplifiers on the tubes, and so far none have blown up.

73 Tom

  bizarre


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 23, 2011, 09:48:14 AM
Quote
The GM tubes have a ***very*** fine wire used for the anode, so there is a very high electric field in the vicinity.

Thus an electron released at the cathode by the photoelectric effect or just a beta wondering into the tube at low energy will have a high probability of being accelerated to an energy sufficient to trigger an avalanche in the tube. Incidentally this is why GM tubes are poor for spectrographic studies, the pulse height is largely independent of the energy of the particle.

A 3-500Z or whatever by contrast has a heated cathode that runs (normally) in a permanent cloud of electrons, with the grid screening them from reaching the anode. There is nothing like the electric field strength and nothing like enough gas (except in some modern tubes Sad ) to cause avalanche breakdown.

Consider a electron being knocked off the grid by a cosmic ray, well given the grid capacitance and the size of the charge on the electron you can work out the change in voltage on the grid (hint is is small). The same applies to an electron knocked off a gas molecule as long as there is insufficient gas and electric field strength to cause an avalanche discharge (Which is a tube design consideration).

Tube breakdown in a sufficiently gassy tube might be triggered by a cosmic ray I suppose,

  Not tube breakdown/flashover, just conduction.

Quote
but realistically that tube would fail in short order anyway if it is that gassy..

  I was not thinking of a high energy photon only striking a gas atom in a tube Dan, I was thinking about it striking any atom in a tube and knocking one or more electrons loose -- thereby causing the tube to briefly conduct due to the several kilovolts present.  When a biased off transmitting tube even briefly conducts there is enough potential to arc the NO contacts on the Tx/Rx bias relay - which could cause major mischief.   The reason I started this thread is because two days ag I received a telephone from an Ham in Idaho whose 8166/4-1000A amplifier  had an event when it was in Rx / biased off.   Rich, ag6k
 
Quote
I don't really buy it as a significant effect.

Regards, Dan.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 23, 2011, 10:00:24 AM
Quote
Quite a lot has been published about semi conductors and radiation. The effects are very dependent on the process and the geometry: at Plessey Semiconductors, we had some logarithmic amplifier ICs in a bipolar process. These were irradiated to such an extent the white alumina substrate turned brown, and yet the change in performance of the three dual amplifier chips couldn't be measured.

But considering the vast number of vacuum tubes of one sort or another - TWTs, magnetrons, klystrodes as well as 'conventional' transmitting tubes in daily use, if it was an effect, it would appear far more frequently than the odd flashover.

  I am not talking about a blitzy flashover, I 'm talking about momentary conduction of a tube that is biased off.  I have occasionally been getting reports of this since the first QST article on parasites appeared in Fall 1988. The last such report was from Idaho on the 20th of this month.  Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 23, 2011, 10:14:32 AM
Quote
There is a semi formal paper that was published fifteen or twenty years ago discussing cosmic radiation and its effect on semiconductors in personal computers.  It provided estimates of the chance of an individual being affected.   The numbers were small, but possible.

  My Toyota Prius has three computers.  Occasionally when I try to accelerate hard the computer-controlled throttle backs off and  acceleration stops.   The fix is to pull over, shut it off and relaunch.  As I understand it, some Prius owners occasionally have more serious computer controlled accelerator problems.  Nissan had similar problems with their computers but they came up with a clever workaround that takes the brakes out of anti-lock mode whenever the accelerator is advanced.  This allows the driver to stop the car even if the throttle is wide open.  Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: M0HCN on October 23, 2011, 10:38:44 AM
I was thinking about it striking any atom in a tube and knocking one or more electrons loose -- thereby causing the tube to briefly conduct due to the several kilovolts present.  
Work the numbers, gate capacitance, charge on an electron... delta V on the gate.

Lets assume a 1pf gate/cathode capacitance (more makes the effect smaller), then knocking an electron off and having it accelerate to a large distance will change the grid voltage by delta V = delta Q /  C = 10^-19 / 10^-12 = 10^-7 V  (Working to orders of magnitude).
It takes 10^7 electrons to change the bias by a volt given a completely open circuit grid @ 1pf...... The only way you are getting that is if the tube avalanches, and if there is enough gas for that you have worse problems (Or you have a hunk of Cs137 on the shelf behind the amp in which case you also have worse problems).
Quote
 The reason I started this thread is because two days ag I received a telephone from an Ham in Idaho whose 8166/4-1000A amplifier  had an event when it was in Rx / biased off.
Interesting, but I would be looking elsewhere.

Regards, Dan.



Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: W8JI on October 23, 2011, 12:49:32 PM
AG6K  says:
Quote
  The reason I started this thread is because two days ag I received a telephone from an Ham in Idaho whose 8166/4-1000A amplifier  had an event when it was in Rx / biased off.

Quote
Interesting, but I would be looking elsewhere.
Regards, Dan.

The common cause of a faults on standby is a gassy tube, although sometimes it can be a HV fault outside the tube. I've seen dozens of cases where a tube will arc on standby. None of it is anything more than a simple tube fault.



Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 23, 2011, 01:25:19 PM
Quote
AG6K  says:
Quote
  The reason I started this thread is because two days ag I received a telephone from an Ham in Idaho whose 8166/4-1000A amplifier  had an event when it was in Rx / biased off.

Quote from: 2E0CHE on Today at 10:38:44 AM
Quote
Interesting, but I would be looking elsewhere.
Regards, Dan.

The common cause of a faults on standby is a gassy tube, although sometimes it can be a HV fault outside the tube. I've seen dozens of cases where a tube will arc on standby. None of it is anything more than a simple tube fault.

  The 8166 is not gassy.
Rich


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 23, 2011, 01:35:20 PM
Quote
Quote from: AG6K on Today at 09:48:14 AM
I was thinking about it striking any atom in a tube and knocking one or more electrons loose -- thereby causing the tube to briefly conduct due to the several kilovolts present. 
Work the numbers, gate capacitance, charge on an electron... delta V on the gate.

  4-1000As have no gate.

Quote
Lets assume a 1pf gate/cathode capacitance (more makes the effect smaller), then knocking an electron off and having it accelerate to a large distance will change the grid voltage by delta V = delta Q /  C = 10^-19 / 10^-12 = 10^-7 V  (Working to orders of magnitude).
It takes 10^7 electrons to change the bias by a volt given a completely open circuit grid @ 1pf...... The only way you are getting that is if the tube avalanches, and if there is enough gas for that you have worse problems (Or you have a hunk of Cs137 on the shelf behind the amp in which case you also have worse problems).

Quote
The reason I started this thread is because two days ago I received a telephone call from an Ham in Idaho whose 8166/4-1000A amplifier  had an event when it was in Rx / biased off.
Interesting, but I would be looking elsewhere.

Regards, Dan.

  Where?


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: M0HCN on October 23, 2011, 02:02:20 PM
4-1000As have no gate.
Ok so I have been doing too much with fets lately....
The math still applies to the grid just the same as it did to the fet gate.

Faulty tube/socket/insulation failure/bias supply fault, something of that type would be my guess.

When fault finding assume the simple faults until you really do need to introduce weird physics (the second type of fault are **RARE**), 99.99%  of the time even the weird ones turn out to have a (with hindsight) trivial cause.

Also, it is often a bad idea to take user reports at face value, "Nothing has changed" then after a week of headscratching it turns out that "Nothing" includes a new PTT cable or upgrading the software or whatever. Been there, the judge ruled it justifiable homicide...... 

Regards, Dan.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 24, 2011, 04:35:09 AM
Quote
AG6K  says:
Quote
  The reason I started this thread is because two days ag I received a telephone from an Ham in Idaho whose 8166/4-1000A amplifier  had an event when it was in Rx / biased off.

Quote from: 2E0CHE on Yesterday at 10:38:44 AM
Quote
Interesting, but I would be looking elsewhere.
Regards, Dan.

Tom Rauch:  The common cause of a faults on standby is a gassy tube, although sometimes it can be a HV fault outside the tube. I've seen dozens of cases where a tube will arc on standby. None of it is anything more than a simple tube fault.

  Tom R.:  The 8166/4-1000A is not gassy. The owner of the 8166/4-1000A amplifier told me he had an external arc because at the he was looking in the direction of the blue flash and he heard a loud bang.  An arc inside a tube does not go bang, it goes tink.  There was no damage to the bias components.  The owner told me what he thought it was but I know you aren't having any of that Tom.  cheers
Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: W8JI on October 24, 2011, 07:22:51 AM
  Tom R.:  The 8166/4-1000A is not gassy. The owner of the 8166/4-1000A amplifier told me he had an external arc because at the he was looking in the direction of the blue flash and he heard a loud bang.  An arc inside a tube does not go bang, it goes tink.  There was no damage to the bias components.  The owner told me what he thought it was but I know you aren't having any of that Tom.  cheers
Rich, ag6k


That's just your take on it. None of that in any way indicates the tube was not gassy.



Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 24, 2011, 08:55:17 AM
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RE: Background Radiation - Could It Be a Vexation ?
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Quote from: AG6K on Today at 04:35:09 AM
  Tom R.:  The 8166/4-1000A is not gassy. The owner of the 8166/4-1000A amplifier told me he had an external arc because at the he was looking in the direction of the blue flash and he heard a loud bang.  An arc inside a tube does not go bang, it goes tink.  There was no damage to the bias components.  The owner told me what he thought it was but I know you aren't having any of that Tom.  cheers
Rich, ag6k


That's just your take on it. None of that in any way indicates the tube was not gassy.

  The owner told he subsequently checked the tube and it was not gassy.   Would an anode-to-gnded grid arc  inside a gassy tube make a bang Tom ?
Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: M0HCN on October 24, 2011, 09:13:16 AM
Not directly, but I could see magnetorestriction in the wiring and possibly even the power transformer making a bang as the current pulse sets up fields between conductors.

I have actually heard this effect in pulsed power applications, the intake room had a sort of ghostly impossible to locate ticking sound coming from everywhere as the wiring in the conduits reacted to fast risetime pulses.

Regards, Dan.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: W8JI on October 24, 2011, 09:18:34 AM
  The owner told he subsequently checked the tube and it was not gassy. 
 


So what? My wife tells me numerology works. People say things, claim things, and think things all the time that are not factual.


Quote
Would an anode-to-gnded grid arc  inside a gassy tube make a bang Tom ?
Rich, ag6k

Yes, if coupled to an outside system it does. It absolutely happens all the time.

When we produced a 3CX3000F7 amplifier new tubes would fault all the time on power up. They would always make a big bang as resistors and unintentional air gaps would arc, and wires jump around during the fault. One big bang, and the tubes would be clear for life.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AH6RR on October 24, 2011, 10:03:23 AM
I have come to the conclusion that Rich was very good friends with Timothy Leary back in the 60's


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 24, 2011, 12:16:28 PM
Quote
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RE: Background Radiation - Could It Be a Vexation ?
« Reply #23 on: Today at 10:03:23 AM »
   
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I have come to the conclusion that Rich was very good friends with Timothy Leary back in the 60's

  YWhat was his callsign?  .  Do you believe that an arc inside a vacuum tubes makes a big bang? 


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: W8JI on October 24, 2011, 01:24:14 PM
  YWhat was his callsign? 


AC1D

Quote
Do you believe that an arc inside a vacuum tubes makes a big bang? 


I do, because I've seen and heard it on many occasions.

Apparently many others do, also.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 24, 2011, 06:19:34 PM
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Quote from: AG6K on Today at 12:16:28 PM
  What was his callsign?
.

AC1D

Quote
Do you believe that an arc inside a vacuum tubes makes a big bang?


I do, because I've seen and heard it on many occasions.

  I remember in high school physics when the instructor put an electric alarm bell in a bell jar, started the current through it and began pumping the air out.   At first the class could hear the bell plainly but as the vacuum  increased the sound level decreased.  When the pressure in the jar was <1mm of Hg the sound was barely there. 
  ••  "You can fool some of the people some of the time,  but you can't fool all of the people all of the time "
-  Abraham Lincoln

Quote
Apparently many others do, also.

  Apparently are others who think it's possible to make stuff up and win a science debate. 
Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 24, 2011, 06:25:14 PM
Quote
Quote
Would an anode-to-gnded grid arc  inside a gassy tube make a bang Tom ?
Rich, ag6k

Tom R.  -- Yes, if coupled to an outside system it does. It absolutely happens all the time.

  Tom's "System" prestidigitation again.

Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AH6RR on October 24, 2011, 07:42:21 PM
To funny Tom that is about right and I thought it was W60LSD since he was on the left coast.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: N3OX on October 24, 2011, 08:36:48 PM
I have actually heard this effect in pulsed power applications, the intake room had a sort of ghostly impossible to locate ticking sound coming from everywhere as the wiring in the conduits reacted to fast risetime pulses.

I have a split ferrite core on a stepper motor controller for one of my antenna switches that ticks when I change bands ;D


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: ND6P on October 25, 2011, 03:36:50 AM
Install a flux capacitor.  Then you can run the amp on banana peels without fear of radiation-induced electron-slippage.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: W8JI on October 25, 2011, 05:02:12 AM
Quote
Quote
Would an anode-to-gnded grid arc  inside a gassy tube make a bang Tom ?
Rich, ag6k

Quote
Tom R.  -- Yes, if coupled to an outside system it does. It absolutely happens all the time.



  Tom's "System" prestidigitation again.

Rich, ag6k

That's right. It is the system.

The 20-200 ampere kick makes all sorts of things move around and make noise, including external arcs.

For your idea to work, the entire amplifier and power supply would have to be floating in a vacuum without any mechanical sound paths to the outside. Even the tube elements would have to be floating with no external mechanical connections that conduct sound.

Most tube elements are also rigidly mounted. Go back to school and look at how the bell was mounted.

ALL of that contributes to noise, no matter how much we want to pretend it does not.

73 Tom


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 25, 2011, 05:18:49 AM
Quote
Quote
Quote
Would an anode-to-gnded grid arc  inside a gassy tube make a bang Tom ?
Rich, ag6k

Quote
Tom R.  -- Yes, if coupled to an outside system it does. It absolutely happens all the time.


Quote from: AG6K on Yesterday at 06:25:14 PM

  Tom's "System" prestidigitation again.

Rich, ag6k

That's right. It is the system.

  The tube is not gassy.

Quote
The 20-200 ampere kick makes all sorts of things move around and make noise, including external arcs.

For your idea to work, the entire amplifier and power supply would have to be floating in a vacuum without any mechanical sound paths to the outside. Even the tube elements would have to be floating with no external mechanical connections that conduct sound

  What sound does a vacuum cap make when it arcs ?  Rich, ag6k

.
Quote
Most tube elements are also rigidly mounted. Go back to school and look at how the bell was mounted.

ALL of that contributes to noise, no matter how much we want to pretend it does not.

73 Tom


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: W8JI on October 25, 2011, 05:27:30 AM
Rich,

You logic is simply terrible in analogies you use.

I suggest you discharge a 20 uF capacitor charged to 3000 volts into the vacuum capacitor and tell us what noise you hear.

The small "tink" you hear WITHOUT the energy storage of a filter capacitor is because the vacuum cap only has a few hundred pF charged.

Try connecting your high pot to an oil filled in parallel with the vacuum cap. Later, add a choke and wiring, a relay gap, and other components and then tell us about the noise level.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 25, 2011, 06:09:15 AM
Quote
W8JI

   
RE: Background Radiation - Could It Be a Vexation ?
« Reply #33 on: Today at 05:27:30 AM »
   
Rich,

You logic is simply terrible in analogies you use.
Tom Rauch

  I test air-variable capacitors with the same high-pot I test vacuum-variable capacitors with.  The crack an air-variable makes when it flashes OVER is at least 30db above  the tink a vacuum capacitor makes when it flashes over.

"You can fool some of the people some of the time but you can't fool all of the people all of the time". -- Abraham Lincoln

Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: W8JI on October 25, 2011, 07:04:17 AM
Re-read what I wrote, and do the experiment.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 25, 2011, 07:56:38 AM
Quote
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RE: Background Radiation - Could It Be a Vexation ?
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Re-read what I wrote, and do the experiment.

  _____
Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: G3RZP on October 25, 2011, 08:18:17 AM
I am a bit lost here. A UV photon enters the tube, knocks of an electron conduction happens and we hear a loud bang. The argument is that if the discharge is in a vacuum, there is only a faint 'tink'. Ergo, if there is a loud bang, it cannot be in the vacuum. Therefore something else must have made the noise, and if there is that much energy discharged, show signs of it. What does?

If the tube flashes over and can be heared as a loud bang, one would expect tube damage, and then Rocky Point effect becomes a probability. But so far the argument seems to be that there's a bang caused by conduction in the tube, but a flashover in the tube can't be heard.

Some contradiction in the original argument here.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 25, 2011, 09:22:36 AM
Quote
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RE: Background Radiation - Could It Be a Vexation ?
« Reply #37 on: Today at 08:18:17 AM »
   
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I am a bit lost here. A UV photon
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enters the tube, knocks of an electron conduction happens and we hear a loud bang.

  more likely a gamma-ray photon or maybe a cosmic-ray photon

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The argument is that if the discharge is in a vacuum, there is only a faint 'tink'.
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  my position:  there wass no arc inside the tube - only sudden but temporary conduction caused by the bumping of electrons. The sudden flow of I through the VHF parasitic resonance in the anode circuit of the 4-1000A/8166 caused it to ring at the  freq. of the parasitic resonance.  Since some of this VHF energy is fed back by the 4-1000A's internal feedback C, regeneration apparently took place.  However, since the 20m tank circuit is a LPF, there was no way for the VHF energy to reach the load.  As a result, the energy ran amuck and an arc to gnd resulted.  This is a common occurrence in stock SB-220s when they intermittently osc. c. 112MHz.   

Ergo, if there is a loud bang, it cannot be in the vacuum.


  agreed Peter.   However, my experiences with T.R. suggest that he will never back down on his position that arcs in a vacuum make a big bang. 

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Therefore something else must have made the noise, and if there is that much energy discharged, show signs of it. What does?

  A 25uF filter C with 2-ohms of ESR that is charged to 5000v has little trouble delivering enough peak-P to make a somewhat stentorian bang through a 15-ohm glitch-R. 

I
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f the tube flashes over and can be heared as a loud bang, one would expect tube damage, and then Rocky Point effect becomes a probability. But so far the argument seems to be that there's a bang caused by conduction in the tube, but a flashover in the tube can't be heard.

Some contradiction in the original argument here.

  Correct Peter, and therein is the (un-admittable) flaw in the expert's agenda.
cheers
Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AH6RR on October 25, 2011, 10:45:41 AM
Dang where's my Ni-Chrome cap?


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 25, 2011, 11:09:56 AM
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RE: Background Radiation - Could It Be a Vexation ?
« Reply #39 on: Today at 10:45:41 AM »
   
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Dang where's my Ni-Chrome cap?

  There is no benefit in using resistance-wire in a VHF suppressor other than to reduce the dissipative burden in the suppressor's R at 28-29 MHz.   
Rich, ag6k



Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: G3RZP on October 25, 2011, 12:02:17 PM
>Correct Peter, and therein is the (un-admittable) flaw in the expert's agenda<


No, Rich, a basic contradiction in the arguments you offer. To be brutally honest, as usual in your arguments.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: W8JI on October 25, 2011, 01:11:27 PM
Rich invented a new clearly impossible theory, that a photon would make a healthy tube conduct, that tube arcs never can cause a big bang.................because someone reportedly told him a tube without gas arced on standby and made a big bang.

Getting to this point took pages of replies.

Was it worth it?


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: KA5N on October 25, 2011, 01:25:04 PM
Rich invented a new clearly impossible theory, that a photon would make a healthy tube conduct, that tube arcs never can cause a big bang.................because someone reportedly told him a tube without gas arced on standby and made a big bang.
Getting to this point took pages of replies.
Was it worth it?

No it was not worth it.   Tom I saw a post by you the other day telling someone to
avoid arguing with people who won't listen.  Please take your own advice and stop
stirring the pot.
This forum has been a waste for several weeks lately.  Please.
Allen




Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: W8JI on October 25, 2011, 01:45:26 PM
Rich invented a new clearly impossible theory, that a photon would make a healthy tube conduct, that tube arcs never can cause a big bang.................because someone reportedly told him a tube without gas arced on standby and made a big bang.
Getting to this point took pages of replies.
Was it worth it?

No it was not worth it.   Tom I saw a post by you the other day telling someone to
avoid arguing with people who won't listen.  Please take your own advice and stop
stirring the pot.
This forum has been a waste for several weeks lately.  Please.
Allen




That's probably good advice. I agree the forum sure went downhill a week or two ago. It is mostly becoming useless noise.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AF6LJ on October 26, 2011, 12:45:41 PM
Getting back to the original discussion which I have been following with considerable interest.....

Large currents ether suddenly established or suddenly reduced to zero do move things, sometimes really big things. An arc in a vacuum will only make sound as the result of the mechanical force of the arc being conducted through the solid objects that make their way to the outside. What I can't buy into is on this planet with an abundance of life that there would be enough cosmic or any other radiation to cause any vacuum tube to arc internally. Stop and think about the number of not only electrons you have to dislodge but the number of ions free or otherwise that have to be created. A cloud of electrons by themselves won't cause the arc.
As soon as those electrons are dislodged they will be sucked up by the anode to be just another bit of noise in the system.

Here is a question for everyone;
How do we know that unexplainable arc (bang) isn't caused by VOCs (volatile Organic Compounds) in the air?




Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: W8JI on October 26, 2011, 01:51:31 PM
Here is a question for everyone;
How do we know that unexplainable arc (bang) isn't caused by VOCs (volatile Organic Compounds) in the air?




We all know, or should know, it isn't radiation. That is physically impossible. We are left with things that cause a HV to ground fault.

I have tubes here that repeatedly will make a "big bang" because, when they fault, things inside the amp will jump around from the surge, relay contacts will arc, capacitors and chokes will make noise, and even the tubes will make a bang.

As a series resistance is added to the supply to limit fault current, the noise is greatly reduced.

There isn't anything magical or mysterious about this. Even the tube noise is not that strange. The anode in some tubes IS the outside of the tube, and in other tubes it connects through a large support stem. There are also supporting structures that anchor the elements in place.

Not only that, the noise can be replicated over and over again with some defective tubes. 50-200 amps as a 3000-6000 volt line pulls to ground moves many things, and can easily creates multiple external arc paths.


73 Tom



Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 26, 2011, 03:02:55 PM
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AF6LJ
Susan A. Robins
   
RE: Background Radiation - Could It Be a Vexation ?
« Reply #48 on: Today at 12:45:41 PM »
   
Getting back to the original discussion which I have been following with considerable interest.....

Large currents ether suddenly established or suddenly reduced to zero do move things, sometimes really big things. An arc in a vacuum will only make sound as the result of the mechanical force of the arc being conducted through the solid objects that make their way to the outside
.

  Correctamundo

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What I can't buy into is on this planet with an abundance of life that there would be enough cosmic or any other radiation to cause any vacuum tube to arc internally.

  Agreed Susan.  The tube does not arc when electrons are knocked loose by fleeting a high-energy photon, the tube simply conducts briefly.   The sudden flow of current pulses the current through the anode's parasitic parallel-resonance formed by the 4-1000A's 7pF anode-C, the lead L, the L/R VHF suppressor's L,  C-tune to gnd and back to the gnded-grids.  In a typical 4-1000A amplifier this resonance is typically near 85MHz. depending on layout.  Much in the same way that a spark transmitter generated RF, the I-pulse rings the parasitic resonance  and generates a VHF damped wave. .  If conditions are right, due to the feedback path in the 4-1000. it is sometimes possible for regeneration of the VHF signal to take place.  Since the 4-1000A's tank L is essentially a VHF RFC, the VHF energy being produced has no where to go so it runs amok before the L, possibly causing arcing, and big bangs. 

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Stop and think about the number of not only electrons you have to dislodge but the number of ions free or otherwise that have to be created. A cloud of electrons by themselves won't cause the arc.
As soon as those electrons are dislodged they will be sucked up by the anode to be just another bit of noise in the system.

  sound analysis. 

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Here is a question for everyone;
How do we know that unexplainable arc (bang) isn't caused by VOCs (volatile Organic Compounds) in the air?

    Volatile organic compounds that are often found in Ham radio stations - such as Jack Daniels - are insulators when in vapor form.
  A good clue as to the cause of the arc is the measured R of the VHF parasitic suppressor resistor: -- I.E., if the R has greatly increased and there is no sign of heat damage on the outside, odds are that the damage was due to brief burst of VHF energy.   If the suppressor R is okay, maybe the arc and big bang was due to fruit flies or moths?

cheers Susan
Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 26, 2011, 03:31:33 PM
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Quote from: AF6LJ, Susan A.  Today at 12:45:41 PM
Here is a question for everyone;
How do we know that unexplainable arc (bang) isn't caused by VOCs (volatile Organic Compounds) in the air?

Quote
We all know, or should know, it isn't radiation.

  Correct Mr. Rauch.  The only result of freeing electrons in the vicinity of +HV on the anode is a very brief flow of I in a tube that had been biased off.   If there happens to be a VHF  resonant circuit in the path of that pulse of current, does it seem possible that the circuit will ring and produce damped-wave VHF energy?255

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That is physically impossible. We are left with things that cause a HV to ground fault.

I have tubes here that repeatedly will make a "big bang" because, when they fault, things inside the amp will jump around from the surge, relay contacts will arc, capacitors and chokes will make noise, and even the tubes will make a bang.

  If this was true then our physics class would have heard the alarm bell ringing loudly in the vacuum inside the bell jar. -- and we did not.   .  .  It's probably not good tor one's reputation to make stuff up in hopes of saving one's bacon.   

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As a series resistance is added to the supply to limit fault current, the noise is greatly reduced.

There isn't anything magical or mysterious about this./quote]

  I know, it's what I have been saying since Oct. 1988.

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[Even the tube noise is not that strange. The anode in some tubes IS the outside of the tube, and in other tubes it connects through a large support stem. There are also supporting structures that anchor the elements in place.

Not only that, the noise can be replicated over and over again with some defective tubes. 50-200 amps as a 3000-6000 volt line pulls to ground moves many things, and can easily creates multiple external arc paths

  The hydra grows more heads.  -  Rich, ag6k.

.
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73 Tom


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: G3TXQ on October 27, 2011, 12:38:47 AM
Rich,

I've been trying to follow this long-running thread, but it's now proving almost impossible because of your inability to structure responses. I'm totally confused as to who-said-what when I read your quotes.

Any chance you could get someone to give you a short lesson in how to do it properly?

Steve G3TXQ


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 27, 2011, 02:16:36 AM
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Rich,

I've been trying to follow this long-running thread, but it's now proving almost impossible because of your inability to structure responses. I'm totally confused as to who-said-what when I read your quotes.

Any chance you could get someone to give you a short lesson in how to do it properly?

Steve G3TXQ

  I've had lotsa help Steve.  Since clicking the Quote button seems to semi-consistently put everything in blue, I stopped using it.  Currently I copy the text I wish to reply to, click REPLY, click the Insert Quote button and paste in the text I am replying to.  I start my replies with the bitten-apple character - which is shift-option k on an Apple computer.  I put insert quote marks before and after each of my replies.   Any suggestions?  tnx
Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: G3TXQ on October 27, 2011, 02:22:39 AM
Any suggestions?

Yes - use the Preview option to check that it looks OK before submitting; and always ensure that your comments appear outside any quoted section - that way it's clear what is the new contribution to the discussion.

73,
Steve G3TXQ


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AF6LJ on October 27, 2011, 09:33:04 AM

    Volatile organic compounds that are often found in Ham radio stations - such as Jack Daniels - are insulators when in vapor form.
  A good clue as to the cause of the arc is the measured R of the VHF parasitic suppressor resistor: -- I.E., if the R has greatly increased and there is no sign of heat damage on the outside, odds are that the damage was due to brief burst of VHF energy.   If the suppressor R is okay, maybe the arc and big bang was due to fruit flies or moths?

cheers Susan
Rich, ag6k

The JD experiment maybe worth trying.

If there is an arc that cannot be explained by some issue with the design of the amplifier itself and cannot be repeated consistently then ether the environment the amplifier is operating in is the cause or some electrical transient exists on the AC mains feeding the amplifier.

I once worked for a company that made microprocessor vending machines, every once and a while a machine would crash and the watch dog timer would take it out of service. Two months later the cause was traced down to a dirty motor in the plant which generated a spike on the circuit shared with final test. Aggressive primary filtering cured the problem.

In electronics there are no unexplainable, random faults; there are simply conditions and causes that are overlooked. 


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 27, 2011, 10:37:40 AM
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The JD experiment maybe worth trying.

  chortle.

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If there is an arc that cannot be explained by some issue with the design of the amplifier itself and cannot be repeated consistently then ether the environment the amplifier is operating in is the cause or some electrical transient exists on the AC mains feeding the amplifier.

  which assumes there is no such thing as background radiation.   However, I know that the next time I drive my Prius it's possible that the computer which controls the gas engine throttle may have an anomaly and I will have to pullover and reboot.  Forrest Gump was right about feces Susan

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I once worked for a company that made microprocessor vending machines, every once and a while a machine would crash and the watch dog timer would take it out of service. Two months later the cause was traced down to a dirty motor in the plant which generated a spike on the circuit shared with final test. Aggressive primary filtering cured the problem.

In electronics there are no unexplainable, random faults; there are simply conditions and causes that are overlooked. 

  assuming there are no photons more energetic than UV.
Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AF6LJ on October 27, 2011, 11:34:53 AM

If there is an arc that cannot be explained by some issue with the design of the amplifier itself and cannot be repeated consistently then ether the environment the amplifier is operating in is the cause or some electrical transient exists on the AC mains feeding the amplifier.
Quote
  which assumes there is no such thing as background radiation.   However, I know that the next time I drive my Prius it's possible that the computer which controls the gas engine throttle may have an anomaly and I will have to pullover and reboot.  Forrest Gump was right about feces Susan

Actually you won't have to pullover and reboot, the computer's watchdog timer will reboot for you.
Background radiation is a fact of life what we are debating is the amount of energy in the background radiation that makes it way though the atmosphere without loosing some or all of that potential to then make it's way through the building housing the amplifier then through the cabinet through a layer of ceramic (or glass) and still have enough energy to free up enough ions to cause an arc.
(sorry for the run on sentence.)

We do experience on a semi-regular basis cosmic ray bursts. In the Internet age such an occurrence as you described could be linked to such a radiation burst if that was indeed the cause. Neutrinos pass though this planet and everything on it daily and are so small the are not disruptive. It is believed this planet has experienced cosmic ray bursts that may be responsible for at least one mass extinction.

I can't quite buy into this theory without some data showing a link between background radiation and a failure mode like this.

Quote
I once worked for a company that made microprocessor vending machines, every once and a while a machine would crash and the watch dog timer would take it out of service. Two months later the cause was traced down to a dirty motor in the plant which generated a spike on the circuit shared with final test. Aggressive primary filtering cured the problem.

In electronics there are no unexplainable, random faults; there are simply conditions and causes that are overlooked. 
  assuming there are no photons more energetic than UV.
Rich, ag6k

I don't have any problem with the existence of high energy photons. One of my best friends has a degree in nuclear engineering. when we are not talking about our pets, cloths, houseplants boyfriends or the rest of that stuff we do talk about science and technology related topics.

I have to say that being a woman who is immersed in computer technology your theory would hold much more water had I seen unexplainable crashes in my PCs. They simply don't behave that way. The computer I am currently using runs Windows XP, the motherboard is twelve years old and the number of times this computer has crashed I can count on one hand, all of which had documentable causes. Of the four computers in this house not a single one has just crashed.

It would be reasonable to expect given a large enough solar or extra-solar event bathing this planet in high energy photons and other forms of ionizing radiation that electronic equipment not sufficiently shielded would incur soft or hard failure.

With that said, thank God for Watch Dog Timers and sensible engineering practice.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 27, 2011, 07:45:34 PM
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Quote from: AG6K on Today at 10:37:40 AM

Quote
Susan:  If there is an arc that cannot be explained by some issue with the design of the amplifier itself and cannot be repeated consistently then ether the environment the amplifier is operating in is the cause or some electrical transient exists on the AC mains feeding the amplifier.

Quote  which assumes there is no such thing as background radiation.   However, I know that the next time I drive my Prius it's possible that the computer which controls the gas engine throttle may have an anomaly and I will have to pullover and reboot.  Forrest Gump was right about feces Susan


Quote
Actually you won't have to pullover and reboot, the computer's watchdog timer will reboot for you.

•  Actually I have to pull the Prius  over, shut down and reboot. 


Quote
Background radiation is a fact of life what we are debating is the amount of energy in the background radiation that makes it way though the atmosphere without loosing some or all of that potential to then make it's way through the building housing the amplifier then through the cabinet through a layer of ceramic (or glass) and still have enough energy to free up enough ions to cause an arc.
(sorry for the run on sentence.)]

•   Backup.  High-energy photons such as gamma and cosmic rays do not cause an arc, they can knock electrons loose inside the electron tube.  The footloose electrons are attracted by  the positive HV on the anode - thereby causing a brief flow of current.  This pulse of current rings the anode's VHF self resonance, the internal feedback-C feeds back some of the VHF energy and if there is enough VHF amplifying ability, regeneration takes place.  Because VHF can not pass throuh a Low Pass output matching network, the VHF energy runs amok and fireworks happen. 

[quoteWe do experience on a semi-regular basis cosmic ray bursts. In the Internet age such an occurrence as you described could be linked to such a radiation burst if that was indeed the cause. Neutrinos pass though this planet and everything on it daily and are so small the are not disruptive. It is believed this planet has experienced cosmic ray bursts that may be responsible for at least one mass extinction.

I can't quite buy into this theory without some data showing a link between background radiation and a failure mode like this
Quote
.

•  Are the Northern lights / aurora borealis and Southern lights / aurora australis a Norse myth?

Quote
I don't have any problem with the existence of high energy photons. One of my best friends has a degree in nuclear engineering. when we are not talking about our pets, cloths, houseplants boyfriends or the rest of that stuff we do talk about science and technology related topics.

I have to say that being a woman who is immersed in computer technology your theory would hold much more water had I seen unexplainable crashes in my PCs. They simply don't behave that way. The computer I am currently using runs Windows XP, the motherboard is twelve years old and the number of times this computer has crashed I can count on one hand, all of which had documentable causes. Of the four computers in this house not a single one has just crashed.

It would be reasonable to expect given a large enough solar or extra-solar event bathing this planet in high energy photons and other forms of ionizing radiation that electronic equipment not sufficiently shielded would incur soft or hard failure.

•  How does one shield against against gamma and cosmic rays ?  Rich, ag6k

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With that said, thank God for Watch Dog Timers and sensible engineering practice.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: QRP4U2 on October 27, 2011, 09:21:21 PM
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whether or not an x-ray of gamma-ray photon could knock an electron loose inside a 3-500Z or 572B and cause conduction to take place?  

I think you would need an intense burst of photons at just the correct frequency to do that. Plus, the metal surfaces being irradiated need to be highly polished, and tube plates are not.

Photoelectric Effect: The electron energy 1/2mV^2 has to equal (hXFp - W), where the work function of the metal is W and Fp is the frequency of the photon, and h is Plancks constant. So for an electron to move away from the plate, an intense burst of radiation at just the right frequncy would have to occur, and overcome the cathode to anode potential, which is postive and would have much greater energy than the photoelectron. So this scenario is highly improbable.

Geiger-Mueller Effect: In a Geiger counter, just the right kind of gas is needed to cause an avalance effect under a high potential.

Apples and oranges.

Phil - AC0OB


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AF6LJ on October 27, 2011, 09:40:54 PM
Quote
Quote from: AG6K on Today at 10:37:40 AM

Quote
Susan:  If there is an arc that cannot be explained by some issue with the design of the amplifier itself and cannot be repeated consistently then ether the environment the amplifier is operating in is the cause or some electrical transient exists on the AC mains feeding the amplifier.

Quote  which assumes there is no such thing as background radiation.   However, I know that the next time I drive my Prius it's possible that the computer which controls the gas engine throttle may have an anomaly and I will have to pullover and reboot.  Forrest Gump was right about feces Susan


Quote
Actually you won't have to pullover and reboot, the computer's watchdog timer will reboot for you.

•  Actually I have to pull the Prius  over, shut down and reboot. 
So you are telling me the computer in your car crashes?
Never heard of a Prius doing this, I take it the dealer has had the car and I must assume they can't fix it.
Well that makes two examples of bad Japanese engendering I have seen in the last two weeks.
At least I can fix the faulty voltage regulator design in my FTDX-400.
That's one car I won't be caught riding in. 

Quote
Background radiation is a fact of life what we are debating is the amount of energy in the background radiation that makes it way though the atmosphere without loosing some or all of that potential to then make it's way through the building housing the amplifier then through the cabinet through a layer of ceramic (or glass) and still have enough energy to free up enough ions to cause an arc.
(sorry for the run on sentence.)]
Quote
•   Backup.  High-energy photons such as gamma and cosmic rays do not cause an arc, they can knock electrons loose inside the electron tube.  The footloose electrons are attracted by  the positive HV on the anode - thereby causing a brief flow of current.  This pulse of current rings the anode's VHF self resonance, the internal feedback-C feeds back some of the VHF energy and if there is enough VHF amplifying ability, regeneration takes place.  Because VHF can not pass throuh a Low Pass output matching network, the VHF energy runs amok and fireworks happen. 

With all due respect how many electrons do you believe are dislodged when this event occurs?
Secondly if an amplifier design is that close to self oscillation at any frequency the engineer should be fired.  I would love to see just one documented case of this happening. I'm sorry I can't buy into this the number of things that would have to go wrong and the amount high energy photons that would have present are very hard to believe. If you have documentation you can point me to I would love to see it.

Quote
We do experience on a semi-regular basis cosmic ray bursts. In the Internet age such an occurrence as you described could be linked to such a radiation burst if that was indeed the cause. Neutrinos pass though this planet and everything on it daily and are so small the are not disruptive. It is believed this planet has experienced cosmic ray bursts that may be responsible for at least one mass extinction.

I can't quite buy into this theory without some data showing a link between background radiation and a failure mode like this
Quote
.

•  Are the Northern lights / aurora borealis and Southern lights / aurora australis a Norse myth?
No and I know that because I have seen it first hand.
I also know those high energy particles are attracted to the poles by the Earth's magnetic field. the only time you see that stuff south of the forty-fifth parallel is when something really big hits us like the CME back in July of 1974 when I was living in central Oregon.

Quote
I don't have any problem with the existence of high energy photons. One of my best friends has a degree in nuclear engineering. when we are not talking about our pets, cloths, houseplants boyfriends or the rest of that stuff we do talk about science and technology related topics.

I have to say that being a woman who is immersed in computer technology your theory would hold much more water had I seen unexplainable crashes in my PCs. They simply don't behave that way. The computer I am currently using runs Windows XP, the motherboard is twelve years old and the number of times this computer has crashed I can count on one hand, all of which had documentable causes. Of the four computers in this house not a single one has just crashed.

It would be reasonable to expect given a large enough solar or extra-solar event bathing this planet in high energy photons and other forms of ionizing radiation that electronic equipment not sufficiently shielded would incur soft or hard failure.

•  How does one shield against against gamma and cosmic rays ?  Rich, ag6k

Quote
With that said, thank God for Watch Dog Timers and sensible engineering practice.
[/quote]

The Earth's atmosphere does block some gamma and cosmic rays. So does concrete and steel.
How much are you talking about?
How many high energy photons does it take to dislodge enough electron to create 40ma of current in the anode of a transmitting tube?

Can you post a link to any papers on this?
I honestly don't see this happening.
If you have an amplifier that is that close to instability simply turning it on would cause this to happen and it would be repeatable and the engineering deficiency could be corrected.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 28, 2011, 03:34:22 AM
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AF6LJ
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Posts: 13


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RE: Background Radiation - Could It Be a Vexation ?
« Reply #57 on: Yesterday at 09:40:54 PM »
   
Reply with quoteQuote
Quote from: AG6K on Yesterday at 07:45:34 PM
Quote
Quote from: AG6K on Today at 10:37:40 AM

Quote
Susan:  If there is an arc that cannot be explained by some issue with the design of the amplifier itself and cannot be repeated consistently then ether the environment the amplifier is operating in is the cause or some electrical transient exists on the AC mains feeding the amplifier.

Quote  which assumes there is no such thing as background radiation.   However, I know that the next time I drive my Prius it's possible that the computer which controls the gas engine throttle may have an anomaly and I will have to pullover and reboot.  Forrest Gump was right about feces Susan


Quote
Actually you won't have to pullover and reboot, the computer's watchdog timer will reboot for you.

•  Actually I have to pull the Prius  over, shut down and reboot.

Quote
So you are telling me the computer in your car crashes?

  yes


Quote
Never heard of a Prius doing this, I take it the dealer has had the car and I must assume they can't fix it.

  it's been in twice for this.  However, it does it seldom, the fix is simple when it happens, and the Prius averages c. 52mpg. 

... ... ...

Quote
Background radiation is a fact of life what we are debating is the amount of energy in the background radiation that makes it way though the atmosphere without loosing some or all of that potential to then make it's way through the building housing the amplifier then through the cabinet through a layer of ceramic (or glass) and still have enough energy to free up enough ions to cause an arc.
(sorry for the run on sentence.)]
Quote
•   Backup.  High-energy photons such as gamma and cosmic rays do not cause an arc, they can knock electrons loose inside the electron tube.  The footloose electrons are attracted by  the positive HV on the anode - thereby causing a brief flow of current.  This pulse of current rings the anode's VHF self resonance, the internal feedback-C feeds back some of the VHF energy and if there is enough VHF amplifying ability, regeneration takes place.  Because VHF can not pass throuh a Low Pass output matching network, the VHF energy runs amok and fireworks happen.

Quote
With all due respect how many electrons do you believe are dislodged when this event occurs?

  I don't know.

Quote
Secondly if an amplifier design is that close to self oscillation at any frequency the engineer should be fired.  I would love to see just one documented case of this happening.

  If you have access to a spectrum analyzer, a tuning pulser, and a SB-220 or similar amplifier, you can observe the damped wave ringing in the anodes' VHF parasitic resonance (c. 110MHz for a SB-220).  This is signal that that initiates regeneration.  . 

Quote
I'm sorry I can't buy into this the number of things that would have to go wrong and the amount high energy photons that would have present are very hard to believe. If you have documentation you can point me to I would love to see it.

  I didn't believe it until I looked through a 75x microscope and saw a sea of gold meltballs inside a kaput 8874. 

Quote
We do experience on a semi-regular basis cosmic ray bursts. In the Internet age such an occurrence as you described could be linked to such a radiation burst if that was indeed the cause. Neutrinos pass though this planet and everything on it daily and are so small the are not disruptive. It is believed this planet has experienced cosmic ray bursts that may be responsible for at least one mass extinction.[/quote]

  So I've heard but I'm not quite old enough to have seen that one.

Quote
I can't quite buy into this theory without some data showing a link between background radiation and a failure mode like this
Quote

  The arc that makes the big bang is not a direct result of high energy photons knocking electrons around inside an electron tube, it's the sudden conduction of current through the VHF parasitic resonance that creates the damped wave VHF signal that regenerates and causes the arc in air that causes the big bang. - note - in a SB-220 this arc typically takes place between the anode heat radiator cap on V-2 and the perforated cover. 
.

Quote
•  Are the Northern lights / aurora borealis and Southern lights / aurora australis a Norse myth?

Quote
No and I know that because I have seen it first hand.
I also know those high energy particles are attracted to the poles by the Earth's magnetic field. the only time you see that stuff south of the forty-fifth parallel is when something really big hits us like the CME back in July of 1974 when I was living in central Oregon.
...... ...

Quote
It would be reasonable to expect given a large enough solar or extra-solar event bathing this planet in high energy photons and other forms of ionizing radiation that electronic equipment not sufficiently shielded would incur soft or hard failure.
[quote•  How does one shield against against gamma and cosmic rays ?  Rich, ag6k]

... ...

Quote
The Earth's atmosphere does block some gamma and cosmic rays. So does concrete and steel.

  Gamma-rays penetrate steel and lead.  Cosmic-rays penetrate this planet.


Quote
How much are you talking about?
How many high energy photons does it take to dislodge enough electron to create 40ma of current in the anode of a transmitting tube?

 I don't know.

Quote
Can you post a link to any papers on this?
I honestly don't see this happening.

  http://www.somis.org/8877-gs2.JPEG

 
Quote
If you have an amplifier that is that close to instability simply turning it on would cause this to happen and it would be repeatable and the engineering deficiency could be corrected.

  The trouble with intermittent VHF parasitic oscillations is that they are not very repeatable.  .  .  The TL-922 has a reputation for occasionally producing a big bang when its ZSAC drops to zero.  At first I thought this was impossible.  However, its the change in I that rings a resonant circuit, so it matters not whether the current went from zero to 180mA or it went from 180mA to 0nA,  either way there is going to briefly be a damped wave 120MHz signal in the 922's anode circuit.  Since there is c. 4300-ohms of XC between the out and in of the 3-500Zs at this freq. regeneration is probably not impossible.
Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 28, 2011, 04:20:40 AM
Quote
Quote
whether or not an x-ray of gamma-ray photon could knock an electron loose inside a 3-500Z or 572B and cause conduction to take place? 

Quote
I think you would need an intense burst of photons at just the correct frequency to do that. Plus, the metal surfaces being irradiated need to be highly polished, and tube plates are not.

  How could the exact frequency of a gamma-ray have anything to do with causing conduction Phil?

... ... ...

Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: W8JI on October 28, 2011, 04:42:20 AM
  The trouble with intermittent VHF parasitic oscillations is that they are not very repeatable.  .  .  The TL-922 has a reputation for occasionally producing a big bang when its ZSAC drops to zero.  At first I thought this was impossible.  However, its the change in I that rings a resonant circuit, so it matters not whether the current went from zero to 180mA or it went from 180mA to 0nA,  either way there is going to briefly be a damped wave 120MHz signal in the 922's anode circuit.  Since there is c. 4300-ohms of XC between the out and in of the 3-500Zs at this freq. regeneration is probably not impossible.
Rich, ag6k

They are only not repeatable for you. That's probably because you blame almost every problem on either a "parasitic", or some bizarre thing like a high energy photon.

For almost everyone else in the world, things can be tested, measured, and confirmed and also follow logical physical behavior.

73 Tom


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: W9PMZ on October 28, 2011, 05:33:31 AM
As a test engineer who is responsible for the production
of cellular PAs, or for that matter anything else,
to suggest a fix for a problem without having
a failure mode analysis with solid evidence and
resolution I would probably not be employed.

Over the past 30 years I have never had a problem
that did not create repeatable results when the requisite
conditions have been met.

I am obviously not as qualified in tube PA
design as some of the contributors herein,
but I do know that if there is a problem it
can be found and found to be repeatable
when you have found the correct circumstance.

Just my 2 cents...

Regards,

Carl -W9PMZ


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 28, 2011, 07:43:23 AM
Quote
Quote from: AG6K on Today at 03:34:22 AM
  The trouble with intermittent VHF parasitic oscillations is that they are not very repeatable.  .  .  The TL-922 has a reputation for occasionally producing a big bang when its ZSAC drops to zero.  At first I thought this was impossible.  However, its the change in I that rings a resonant circuit, so it matters not whether the current went from zero to 180mA or it went from 180mA to 0nA,  either way there is going to briefly be a damped wave 120MHz signal in the 922's anode circuit.  Since there is c. 4300-ohms of XC between the out and in of the 3-500Zs at this freq. regeneration is probably not impossible.
Rich, ag6k


Quote
Tom Rauch: They are only not repeatable for you. That's probably because you blame almost every problem on either a "parasitic", or some bizarre thing like a high energy photon.

  Tom R. has never seen an aurora?

Quote
For almost everyone else in the world, things can be tested, measured, and confirmed and also follow logical physical behavior.

73 Tom

  I've measured the R of VHF suppressor resistors that were paralleled with 8mm Ag-plated Cu strap, and the R had more than tripled after a big bang.  Does it make sense that HF energy could haave done this damage?
Rich, ag6k. 



Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 28, 2011, 08:25:21 AM
Quote
Carl, W9PHZ:  As a test engineer who is responsible for the production
of cellular PAs, or for that matter anything else,
to suggest a fix for a problem without having
a failure mode analysis with solid evidence and
resolution I would probably not be employed

  Two Hams who have access to spectrum analyzers have tested SB-220s and found that when they are  keyed between Tx and standby with a pulser they produce damped wave energy pulses at c. 110MHz near their anodes.   Nobody who understands spark transmitters should be surprised by this.  On the 3-500Z's tech data sheet it's rated for max input in "Amplifier and Oscillator Service" up to 110MHz.

Quote
Over the past 30 years I have never had a problem
that did not create repeatable results when the requisite
conditions have been met.

I am obviously not as qualified in tube PA
design as some of the contributors herein,
but I do know that if there is a problem it
can be found and found to be repeatable
when you have found the correct circumstance.

  Toyota has  not announced that they found a solution to their rare full-on acceleration problem in vehicles with ABS.  Nissan used to have the same problem but their fix was to disable ABS whenever the throttle was open.  This allows the brakes to lock the wheels and stop the vehicle even at full-throttle.  For owners of  Toyota vehicles with ABS that  experience full-on throttle, the fix is to place the transmission in Neutral, pull over, stop the vehicle, shut it off, and restart.
- note -  Audi GMBH initially had the same problem when they started using ABS on vehicles with computer-controlled throttles.  CBS' 60-Minutes had a segment on it.    Rich, ag6k

Quote
Just my 2 cents...

Regards,

Carl -W9PMZ


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: QRP4U2 on October 28, 2011, 10:34:37 AM
I was referring only to the photoelectric effect for the PE formula given, not to the ionization of gas as in a GC.

Quote
How could the exact frequency of a gamma-ray have anything to do with causing conduction Phil?



Because the work function W of the metal has to be overcome by the photon energy in order to give the electron enough energy to travel, as per the equation.

http://physics.about.com/od/quantumphysics/a/photoelectric_2.htm

http://hyperphysics.phy-astr.gsu.edu/hbase/mod1.html

Phil - AC0OB


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: QRP4U2 on October 28, 2011, 10:53:12 AM
Quote
If there is an arc that cannot be explained by some issue with the design of the amplifier itself and cannot be repeated consistently then ether the environment the amplifier is operating in is the cause or some electrical transient exists on the AC mains feeding the amplifier.


Exactly. We have no need to relegate a macro-physical occurrence to some esoteric quantum mechanical theory.

I have seen an accumulation of dust whiskers on a high voltage part of the circuit, such as the final's RF choke or filter cap before the RF choke, cause a momentary arc. Occasional vacuuming cured the problem.  :D

An HV arc outside a tube is similar to lightning; aside from the HV potential it has two other characteristics, light and sound. Light is generated because of the ionization of the gases in the arc channel and the sound is the compression wave from the heating of the ionization channel.

The compression wave may bounce around inside the cabinet and sound worse than it really is.  

This thread has really gotten away from the original question.

Rich, recommend trying one topic at a time and focusing on it, rather than fixating on parasitic oscillations.  :)


Phil


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AF9J on October 29, 2011, 05:22:51 PM
Wow!  Some of these posts were hard to read!  ;D

Just my brief, 2 cents worth - Rich, I gather that you think a gamma ray or other high energy photon, hit the tube element, and knocked free an electron, causing an avalanche effect, and a discharge in the tube?  Sorry but the nuclear physics, and quantum mechanics I had for my degree in Nuclear Engineering disagrees with this theory.  For starters the atmosphere is thick enough to attenuate most gamma rays and x-rays (forget about UV - not enough energy in it to do the dirty work).  The cross section (which is a definition for the probability) for collision of gamma rays and X-rays with the materials in a tube, is rather small. So, they really don't have a marked effect on materials, until the flux of them is pretty high.  Could the effect you're postulating, occur with the the low flux levels of gamma rays and x-rays we experience from background radiation?  Sure, BUT, the probability is so low, as to effectively be zero.

I think you'd better look at a another cause.

73,
Ellen - AF9J   


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 30, 2011, 05:20:05 AM
Quote
AF9J
   
RE: Background Radiation - Could It Be a Vexation ?
« Reply #66 on: Yesterday at 05:22:51 PM »
   
Wow!  Some of these posts were hard to read!  Grin

Just my brief, 2 cents worth - Rich, I gather that you think a gamma ray or other high energy photon, hit the tube element, and knocked free an electron, causing an avalanche effect, and a discharge in the tube?
  NO.  One more time:  The loosed electrons cause the the tube to briefly conduct.  This pulse of anode-I rings the VHF resonant circuit in the anode whereupon it generats a damped wave VHF signal in the same way that a spark transmitter generated RF.  The feedback-C inside the amplifying device feeds some of the VHF signal back to the input where it can be amplified.  If  VHF gain is high enough, regeneration takes place and a lager amount of VHF energy appears at the anode.  If this energy can not reach the load, it can run amok and cause arcing at the Tune-C or the bandswitch.  This is why the Tune-C in factory-stock SB-220s and TL-922s often has arc-marks. 
- note - the purpose of a VHF suppressor is to reduce VHF amplification to reduce the chance of VHF oscillation.   

Quote
> Sorry but the nuclear physics, and quantum mechanics I had for my degree in Nuclear Engineering disagrees with this theory.

.[/quote]
  Good, it should not agree because you did not understand what I wrote.

 
Quote
For starters the atmosphere is thick enough to attenuate most gamma rays and x-rays (forget about UV - not enough energy in it to do the dirty work).  The cross section (which is a definition for the probability) for collision of gamma rays and X-rays with the materials in a tube, is rather small. So, they really don't have a marked effect on materials,


  So something is wrong with my Geiger-Muller counter?
cheers Ellen.  Rich, ag6k

Quote
until the flux of them is pretty high.  Could the effect you're postulating, occur with the the low flux levels of gamma rays and x-rays we experience from background radiation?  Sure, BUT, the probability is so low, as to effectively be zero.

I think you'd better look at a another cause.

73,
Ellen - AF9J   


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: W8JI on October 30, 2011, 08:54:41 AM
So now he is apparently claiming:

1.) a tube in cut-off conducts enough to overcome bias from a photon event

2.) this event (that everyone knows is impossible) rings a parasitic circuit

3.) The parasitic causes a vacuum tube that saturates at a few amps to suddenly draw dozens or hundreds of amperes, something it cannot do with emission current no matter what the grid bias

4.) the parasitic is the cause, and not gas, and the parasitic in a tube on standby was trigged by the "photon event"

5.) the compelling evidence this can happen is a Prius automobile's computer system sometimes quits while he is driving 

Did I miss anything?


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AF9J on October 30, 2011, 09:04:03 AM
Rich, you're forgetting that a Geiger counter has a gas that will avalanche conduct, much more readily than the (mostly vacuum) that a power tube has.  Also, the collision probability is so low for a gamma ray or x-ray, I don't think you can even count on it 99.99999% of the time.  As it is, for a vacuum tube, you'd probably need hundreds of electrons being released, to have even something close to an avalanche effect in a vacuum tube - not the two, three or four that a typical gamma ray would knock free.  Besides, the collision cross sections of reaction are pretty low.  They're not like the cross sections for low energy neutrons into U235 or PU239.  They're orders of magnitude lower. It's one of the reasons why flux levels and exposure times, for a SPECIFIC AREA of material (not all over it), are what determine when gamma rays become an issue with a material.  Exposure time of a tube to background radiation is one thing, but can you guarantee that the same spot on a tube element, will get hammered with enough random gamma rays, to dump enough electrons at a specific time, to create an avalanche effect?  No.

And Tom, no, you didn't miss Rich's latest postulation.   ;)


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 30, 2011, 09:41:04 AM
Quote
W8JI, Tom Rauch
   
RE: Background Radiation - Could It Be a Vexation ?
« Reply #68 on: Today at 08:54:41 AM »
   
Reply with quoteQuote
So now he is apparently claiming:

1.) a tube in cut-off conducts enough to overcome bias from a photon event

  the bias V is still there but electrons get knocked loose when high-energy photons collide with atoms inside the envelope.  This causes electrons to flow if the anode +HV is present. 

Quote
2.) this event (that everyone knows is impossible) rings a parasitic circuit

  I doubt that everyone thinks it impossible that electrons can be knocked loose.

Quote
3.) The parasitic causes a vacuum tube that saturates at a few amps to suddenly draw dozens or hundreds of amperes, something it cannot do with emission current no matter what the grid bias

  Not hundreds of amperes.  TL-922s are known to be able to have a big bang event that damages its VHF parasitic suppressor resistors when the idle current drops from c. 180mA to zero.

Quote
4.) the parasitic is the cause, and not gas, and the parasitic in a tube on standby was trigged by the "photon event"/quote]

  I used to think it impossible but now I'm convinced that a tube can albeit rarely oscillate on standby or do so as it switches from normal ZSAC to standby,  The missing piece of the puzzle was how was the tube able to draw enough current to blow the 1A grid-gnd RFCs when the bias relay contacts are open.  The answer to that is when the tube conducts, the relay contact gap arcs, and since a metal vapor arc has only about 15v-drop.  This still leaves several kV to do mischief.

Quote
[5.) the compelling evidence this can happen is a Prius automobile's computer system sometimes quits while he is driving

  The computer does not quit in the Prius, it gets confused and will not allow the vehicle accelerate at the usual rate - but the vehicle continues on.

Quote
Did I miss anything?

  Mmmmm .  .  .  pretty much everything.  Did you see the aurora in Georgia Tom?
Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: G3RZP on October 30, 2011, 09:53:09 AM
One of the old MIL STD Handbooks (might have been 217) had some data on reliability of tubes under irradiation. Since they were irradiating with neutrons in very large speeds and densities, (which would be more likely to knock electrons out) with tubes under power and got very long lives, it seems more than unlikely.

In any case, to make the parasitic circuit ring with any amplitude, it will need a pretty large current pulse even with a Q of 10. That is not even a few electrons.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AF6LJ on October 30, 2011, 10:07:10 AM
Okay a little perspective here.

If the tube is cut off no current is going to flow if a few thousand electrons are somehow, some way knocked loose. Would this be enough to overcome the bias if the tube is cut off twice or three times past cutoff.?
No it wouldn't. That resonant circuit could have a Q of 5000 and if there isn't enough electrons to cause current to flow, no Ringy-dingy no regeneration, no big bang caused by background radiation or anything else for that matter.

Rich;
If the tube is cut off, it's cut off there must be electrons flowing from cathode to anode for there to be any kind of oscillation.

To address something you brought up several posts back; I have no doubt 90-100MHZ spurs are seen on a spectrum analyzer when you send a series of dits or use a pulser to drive the exciter; the real question is how far below the PEP output of the fundamental are those spurs?

Back in the day I tuned S and L band emitter driven transistor amplifiers, it was extremely difficult to build an amplifier that didn't have some resonant component in the output or input that existed along with the matching networks. You just don't want them to have a very high Q.

And as a bit of trivia;
From what I remember one ampere second is 6.2 x 1023 electrons per second. I could be off by a couple of orders of magnitude however you get the idea you have to knock off a lot of electrons to raise the anode current in a tube, even to raise the tube's anode current by one femto amp. 1 x 10-15 amperes.

One more thing while I am getting ready to head out to the dog show....

Rich;
If by some means electrons get knocked off it's doubtful if there would be any current flowing since for an instant the anode would be more positive than the instant before but since the distance those electrons would have traveled would be so short no plate current would flow as a result of this action. Electrons are in motion all the time in that anode the few that would had been freed would simply add to the random motion of the guzillons of electrons that were in motion at that instant.

Okay see Y'all later off to the dog show.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: KA5N on October 30, 2011, 10:09:44 AM
If you are fearful of background radiation then just line your shack with lead.
Ought to do the job, and it will match your aluminum foil hat.

Allen


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 30, 2011, 01:32:45 PM
Quote
G3RZP
RE: Background Radiation - Could It Be a Vexation ?
« Reply #71 on: Today at 09:53:09 AM »
   
Reply with quoteQuote
One of the old MIL STD Handbooks (might have been 217) had some data on reliability of tubes under irradiation. Since they were irradiating with neutrons in very large speeds and densities, (which would be more likely to knock electrons out) with tubes under power and got very long lives, it seems more than unlikely.

  This thread is not about tube life vs. neutron bombardment.
Rich, ag6k


Quote
In any case, to make the parasitic circuit ring with any amplitude, it will need a pretty large current pulse even with a Q of 10. That is not even a few electrons.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 30, 2011, 02:15:40 PM
Quote
AF6LJ
Member

RE: Background Radiation - Could It Be a Vexation ?
« Reply #72 on: Today at 10:07:10 AM »
   
Reply with quoteQuote
Okay a little perspective here.

If the tube is cut off no current is going to flow if a few thousand electrons are somehow, some way knocked loose. Would this be enough to overcome the bias if the tube is cut off twice or three times past cutoff.?  No it wouldn't.

  Would the presence of bias V disapppear the bumped loose electrons?


Quote
That resonant circuit could have a Q of 5000 and if there isn't enough electrons to cause current to flow, no Ringy-dingy no regeneration, no big bang caused by background radiation or anything else for that matter.

Rich;
If the tube is cut off, it's cut off there must be electrons flowing from cathode to anode for there to be any kind of oscillation.

  The electrons that are bumped loose could come from anything inside the envelope.

Quote
To address something you brought up several posts back; I have no doubt 90-100MHZ spurs are seen on a spectrum analyzer when you send a series of dits or use a pulser to drive the exciter; the real question is how far below the PEP output of the fundamental are those spurs?

  During the test the RF input and output is shorted and the pulser keys the T/R relay so that ZSAC go off and on repeatedly.   The spectrum analyzer probe is placed a couple of inches from the anodes.


Quote
Back in the day I tuned S and L band emitter driven transistor amplifiers, it was extremely difficult to build an amplifier that didn't have some resonant component in the output or input that existed along with the matching networks. You just don't want them to have a very high Q.

 This is what General Electric's G.W. Fyler told us in 1935. 
Conclusions

"In the elimination of parasites from a transrmitter, the circuits should be kept as simple as possib1e to prevent complex resonance condition.. Radio frequency choke coils and shuntfeed circuits should be kept at a minimum. Wide band neutralization circuits are desirable. The grids of vacuum tubes should be effectIvely by-passed capacitively to the cathode through a capacity, and inductance added next to the plates of the tubes to eliminate shortwave parasites. If necessary, the plate or grid parasitic circuits should be damped with resistance. Inductively coupled rather than capacitively coupled Input and output circuits should be used wherever possible. The mechanical layout of a shortwave transmitter should be well planned with short lesds and compact tank circuits to keep the current where it is supposed to be and to minimize stray coupling between circuits."

G. W. Fyler September, 1935

Quote
And as a bit of trivia;
From what I remember one ampere second is 6.2 x 1023 electrons per second. I could be off by a couple of orders of magnitude however you get the idea you have to knock off a lot of electrons to raise the anode current in a tube, even to raise the tube's anode current by one femto amp. 1 x 10-15 amperes.

  If the tube has VHF amplifying ability, then what?

Quote
... ... ...
Rich;
If by some means electrons get knocked off it's doubtful if there would be any current flowing since for an instant the anode would be more positive than the instant before but since the distance those electrons would have traveled would be so short no plate current would flow as a result of this action.

  So  electrons that come from the 3-500Z's Th-W filament are attracted by the + several kV on the anode - and anode current flows, but electrons that get knocked off of say Mo atoms in the grid wires are not attracted by the + several kV -  so no current flows and no ringy dingy results?
cheers
• Rich, ag6k

Quote
Electrons are in motion all the time in that anode the few that would had been freed would simply add to the random motion of the guzillons of electrons that were in motion at that instant.

Okay see Y'all later off to the dog show.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 30, 2011, 02:27:04 PM
Quote
AF9J
   
RE: Background Radiation - Could It Be a Vexation ?
« Reply #69 on: Today at 09:04:03 AM »
   
Reply with quoteQuote
Rich, you're forgetting that a Geiger counter has a gas that will avalanche conduct, much more readily than the (mostly vacuum) that a power tube has.

  the power tube does not avalanche or arc internally.   
Who said it did ?
•  Rich, ag6k


 
Quote
...


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: G3RZP on October 30, 2011, 02:31:23 PM
But the amount of electrons that could be produced by a collision is too small to initiate the effects claimed. If heavy neutron bombardment can't do it, a cosmic ray won't!

Really, Rich, you should take to writing science fiction or science fantasy. It would probably pay better, too.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 30, 2011, 02:39:01 PM
Quote
G3RZP, Peter C.

RE: Background Radiation - Could It Be a Vexation ?
« Reply #71 on: Today at 09:53:09 AM »
   
Reply with quoteQuote
One of the old MIL STD Handbooks (might have been 217) had some data on reliability of tubes under irradiation. Since they were irradiating with neutrons in very large speeds and densities, (which would be more likely to knock electrons out) with tubes under power and got very long lives, it seems more than unlikely.

In any case, to make the parasitic circuit ring with any amplitude, it will need a pretty large current pulse even with a Q of 10. That is not even a few electrons.

  Peter:  What if the electron tube has a  modest amount of amplification at the VHF parasitic -resonance in its anode circuit?
•  Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: N4MPM on October 30, 2011, 03:08:48 PM
This is beginning to resemble the story about Pig wrestling. :P ::) :o


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: W8JI on October 30, 2011, 04:24:21 PM
This is beginning to resemble the story about Pig wrestling. :P ::) :o

The rational, logical, educational value of this forum took a big hit a few weeks ago. It's almost like the Twilight Zone now.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AF6LJ on October 30, 2011, 05:27:09 PM
Quote

  the power tube does not avalanche or arc internally.   
Who said it did ?
•  Rich, ag6k

See your very first posts in this thread Rich for the answer to this.






The fork came up clean a day or so ago, I think this thread is done.

Have a nice day everyone and thanks for the interesting exchange. Oh and.. We left with a dog and came home with a Champion for anyone who cares :)



Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 30, 2011, 06:04:42 PM
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AF6LJ
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RE: Background Radiation - Could It Be a Vexation ?
« Reply #81 on: Today at 05:27:09 PM »
   
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Quote

  the power tube does not avalanche or arc internally.   
Who said it did ?
•  Rich, ag6k

See your very first posts in this thread Rich for the answer to this.

  My position has always been that an arc which makes a big bang can not be  inside a vacuum tube.
Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 30, 2011, 06:07:23 PM
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RE: Background Radiation - Could It Be a Vexation ?
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Quote from: N4MPM on Today at 03:08:48 PM
This is beginning to resemble the story about Pig wrestling. Tongue Roll Eyes Shocked

The rational, logical, educational value of this forum took a big hit a few weeks ago. It's almost like the Twilight Zone now.

  Tom R.:  Did you see the aurora in Georgia?
Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: W8JI on October 30, 2011, 11:35:29 PM
Have a nice day everyone and thanks for the interesting exchange. Oh and.. We left with a dog and came home with a Champion for anyone who cares :)



At least there is something useful and of interest in this thread.

What kind of dog? We raise what we are gifted. People dump their unwanted dogs on our road, because it is a very rural dirt road. I have cameras now that record license numbers. Once in a while a photon blurs the license number, it almost looks like dust but I know it can't ever be the most obvious. :-)

 


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AF6LJ on October 31, 2011, 05:25:51 AM
Have a nice day everyone and thanks for the interesting exchange. Oh and.. We left with a dog and came home with a Champion for anyone who cares :)



At least there is something useful and of interest in this thread.

What kind of dog? We raise what we are gifted. People dump their unwanted dogs on our road, because it is a very rural dirt road. I have cameras now that record license numbers. Once in a while a photon blurs the license number, it almost looks like dust but I know it can't ever be the most obvious. :-)

 

Chesapeake Bay Retrievers, my roommate has two.
One spayed bitch that isn't show quality, and her boy who just made breed conformation.

We now return you to our regularly scheduled thread.  


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: N2EY on October 31, 2011, 05:56:35 AM
To answer the title question:

No, it couldn't.



Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 31, 2011, 07:21:20 AM
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AG6K
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RE: Background Radiation - Could It Be a Vexation ?
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AF6LJ
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RE: Background Radiation - Could It Be a Vexation ?
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Okay a little perspective here.

If the tube is cut off no current is going to flow if a few thousand electrons are somehow, some way knocked loose. Would this be enough to overcome the bias if the tube is cut off twice or three times past cutoff.?  No it wouldn't.

  Would the presence of bias V disapppear the bumped loose electrons?


Quote
That resonant circuit could have a Q of 5000 and if there isn't enough electrons to cause current to flow, no Ringy-dingy no regeneration, no big bang caused by background radiation or anything else for that matter.

Rich;
If the tube is cut off, it's cut off there must be electrons flowing from cathode to anode for there to be any kind of oscillation.

  The electrons that are bumped loose could come from anything inside the envelope.

Quote
To address something you brought up several posts back; I have no doubt 90-100MHZ spurs are seen on a spectrum analyzer when you send a series of dits or use a pulser to drive the exciter; the real question is how far below the PEP output of the fundamental are those spurs?

  During the test the RF input and output is shorted and the pulser keys the T/R relay so that ZSAC go off and on repeatedly.   The spectrum analyzer probe is placed a couple of inches from the anodes.


Quote
Back in the day I tuned S and L band emitter driven transistor amplifiers, it was extremely difficult to build an amplifier that didn't have some resonant component in the output or input that existed along with the matching networks. You just don't want them to have a very high Q.

 This is what General Electric's G.W. Fyler told us in 1935.
Conclusions

"In the elimination of parasites from a transrmitter, the circuits should be kept as simple as possib1e to prevent complex resonance condition.. Radio frequency choke coils and shuntfeed circuits should be kept at a minimum. Wide band neutralization circuits are desirable. The grids of vacuum tubes should be effectIvely by-passed capacitively to the cathode through a capacity, and inductance added next to the plates of the tubes to eliminate shortwave parasites. If necessary, the plate or grid parasitic circuits should be damped with resistance. Inductively coupled rather than capacitively coupled Input and output circuits should be used wherever possible. The mechanical layout of a shortwave transmitter should be well planned with short lesds and compact tank circuits to keep the current where it is supposed to be and to minimize stray coupling between circuits."

G. W. Fyler September, 1935

Quote
And as a bit of trivia;
From what I remember one ampere second is 6.2 x 1023 electrons per second. I could be off by a couple of orders of magnitude however you get the idea you have to knock off a lot of electrons to raise the anode current in a tube, even to raise the tube's anode current by one femto amp. 1 x 10-15 amperes.

  If the tube has VHF amplifying ability, then what?

Quote
... ... ...
Rich;
If by some means electrons get knocked off it's doubtful if there would be any current flowing since for an instant the anode would be more positive than the instant before but since the distance those electrons would have traveled would be so short no plate current would flow as a result of this action.

  So  electrons that come from the 3-500Z's Th-W filament are attracted by the + several kV on the anode - and anode current flows, but electrons that get knocked off of say Mo atoms in the grid wires are not attracted by the + several kV -  so no current flows and no ringy dingy results?
cheers
• Rich, ag6k

Quote
Electrons are in motion all the time in that anode the few that would had been freed would simply add to the random motion of the guzillons of electrons that were in motion at that instant.

Okay see Y'all later off to the dog show.
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RE: Background Radiation - Could It Be a Vexation ?
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RE: Background Radiation - Could It Be a Vexation ?
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Rich, you're forgetting that a Geiger counter has a gas that will avalanche conduct, much more readily than the (mostly vacuum) that a power tube has.

  the power tube does not avalanche or arc internally.   
Who said it did ?
•  Rich, ag6k


 
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RE: Background Radiation - Could It Be a Vexation ?
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But the amount of electrons that could be produced by a collision is too small to initiate the effects claimed. If heavy neutron bombardment can't do it, a cosmic ray won't!

Really, Rich, you should take to writing science fiction or science fantasy. It would probably pay better, too.
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RE: Background Radiation - Could It Be a Vexation ?
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One of the old MIL STD Handbooks (might have been 217) had some data on reliability of tubes under irradiation. Since they were irradiating with neutrons in very large speeds and densities, (which would be more likely to knock electrons out) with tubes under power and got very long lives, it seems more than unlikely.

In any case, to make the parasitic circuit ring with any amplitude, it will need a pretty large current pulse even with a Q of 10. That is not even a few electrons.

  Peter:  What if the electron tube has a  modest amount of amplification at the VHF parasitic -resonance in its anode circuit?
•  Rich, ag6k
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RE: Background Radiation - Could It Be a Vexation ?
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This is beginning to resemble the story about Pig wrestling. Tongue Roll Eyes Shocked

  It's a story about wrestling with the truth about high-energy photons ability to bust loose electrons.  The laugher is that the recent ionized N2 (red) aurora seen in the State of Georgia - where the Doubting Thomas lives - is estimated to have had a current of >1,000,000 Amperes - or 6.24 x 10^24 electrons.
Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 31, 2011, 07:37:14 AM
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  the power tube does not avalanche or arc internally.   
Who said it did ?
•  Rich, ag6k

See your very first posts in this thread Rich for the answer to this.

  I looked and I saw no place where I said an arc was inside the tube.   How about posting a quote?  tnx
  I have never autopsied a tube that was gassy/glowed blue with HV -  that had an arc mark on the anode - but I've seen lots of arced bandswitches and pitted Tune-C plates in amps that had a history of big bangs.

Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 31, 2011, 07:44:28 AM
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RE: Background Radiation - Could It Be a Vexation ?
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Quote from: AF6LJ on Yesterday at 05:27:09 PM
Have a nice day everyone and thanks for the interesting exchange. Oh and.. We left with a dog and came home with a Champion for anyone who cares Smiley



At least there is something useful and of interest in this thread.

What kind of dog? We raise what we are gifted. People dump their unwanted dogs on our road, because it is a very rural dirt road. I have cameras now that record license numbers. Once in a while a photon blurs the license number, it almost looks like dust but I know it can't ever be the most obvious. :-)

 
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RE: Background Radiation - Could It Be a Vexation ?
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Quote from: W8JI on Yesterday at 11:35:29 PM
Quote from: AF6LJ on Yesterday at 05:27:09 PM
Have a nice day everyone and thanks for the interesting exchange. Oh and.. We left with a dog and came home with a Champion for anyone who cares Smiley



At least there is something useful and of interest in this thread.

What kind of dog? We raise what we are gifted. People dump their unwanted dogs on our road, because it is a very rural dirt road. I have cameras now that record license numbers. Once in a while a photon blurs the license number, it almost looks like dust but I know it can't ever be the most obvious. :-)

 

Chesapeake Bay Retrievers, my roommate has two.
One spayed bitch that isn't show quality, and her boy who just made breed conformation.

We now return you to our regularly scheduled thread. 

   the lingering smell of red herring?

Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: QRP4U2 on October 31, 2011, 10:38:15 AM
Rich,

Regarding Auroras:

Now you're talking about another entirely different mechanism: the collision of energetic charged particles from the Sun with atoms in the thermosphere that interact with the Earth's magnetic field.

 Phil - AC0OB


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 31, 2011, 11:58:09 AM
   
RE: Background Radiation - Could It Be a Vexation ?
« Reply #90 on: Today at 10:38:15 AM »
   
Rich,

Regarding Auroras:

Now you're talking about another entirely different mechanism: the collision of energetic charged particles from the Sun with atoms in the thermosphere that interact with the Earth's magnetic field.

 Phil - AC0OB
[/quote]

  Charged particles contribute to auroras, but. higher energy photons of EM radiation also contribute to auroras because they can also bump  electrons into a higher orbit, and when these  electrons fall back into a lower orbit  they emit photons at a specific wavelength - such as red for N2, UV for Hg,  and blue for O2.  Higher energy photons cause conduction in Geiger-Muller tubes, and they can cause momentary  current flow in vacuum tubes. 
Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: M0HCN on October 31, 2011, 01:56:44 PM
But nowhere near enough to be in any way significant without gas to provide for avalanche breakdown......

Do the math already, this is not hard to demonstrate, dV=dQ/C, grid capacitance and the charge on the electron, work it from there, not hard. This is high school level physics, not exactly university level stuff (I wish this forum software supported LaTEX markup).

Hell getting a non avalanche breakdown tube to work as a particle detector takes MAJOR effort with the preamplifier and that is with a tube designed for proportional counting, look at the pain folks have getting helium three neutron detector tubes to work without excess noise.

You really need to look to ordinary physics here, think forces between current carrying conductors, magnetorestriction, that kind of stuff, not weird shit happening in the switching device (Be it conventional tube, spark gap, thyratron or large solid state switch), bangs in high energy electronics are not always the result of a arc occurring where it can be directly seen or heard.

Regards, Dan.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 31, 2011, 02:34:59 PM
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2E0CHE
   
RE: Background Radiation - Could It Be a Vexation ?
« Reply #92 on: Today at 01:56:44 PM »
   
But nowhere near enough to be in any way significant without gas to provide for avalanche breakdown.... ... ... ..

  One more time:  Hello,   There is no breakdown or arc inside the tube.  The tube briefly conducts, rings the anode-circuit's parasitic VHF resonance, which makes a damped wave VHF signal - which is than amplified and re-amplified until things largely run amok because VHF energy can not pass through the LowPass Pi-tank to reach the load.
Rich, ag6k

...


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AF6LJ on October 31, 2011, 03:06:53 PM
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2E0CHE
   
RE: Background Radiation - Could It Be a Vexation ?
« Reply #92 on: Today at 01:56:44 PM »
   
But nowhere near enough to be in any way significant without gas to provide for avalanche breakdown.... ... ... ..

  One more time:  Hello,   There is no breakdown or arc inside the tube.  The tube briefly conducts, rings the anode-circuit's parasitic VHF resonance, which makes a damped wave VHF signal - which is than amplified and re-amplified until things largely run amok because VHF energy can not pass through the LowPass Pi-tank to reach the load.
Rich, ag6k

...

This can't happen if the amplifier is sitting idle, it can't even happen in a properly designed amplifier.
There isn't going to be enough electrons dislodged by some cosmic ray, or high energy photon.

If this could even happen, how do you think we would have made it to the moon and back as many times as we did?

There is nowhere on the net I can find any documentation for this ever occurring.
Nobody has written any papers on this.

Your Geiger tube does it because there is a large bias on the electrodes and the gas inside is at a rather low pressure.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: W8JI on October 31, 2011, 04:40:04 PM
Summary of AG6K's tube arc proof in a 4-1000 amplifier:

1.) There is aurora

2.)  Gas filled HV Geiger-Muller tubes occasionally have a few microampere "tic" when exposed to room radiation

3.) A Prius computer occasionally locks up

4.) Someone said a spectrum analyzer shows a 100MHz pulse when an SB220's relay is rapidly keyed off and on with shorted input and output ports and a probe inches from the anode

5.) A bell does not ring in a vacuum

6.) Sue's dog is a red herring

 


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 31, 2011, 05:15:22 PM
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RE: Background Radiation - Could It Be a Vexation ?
« Reply #95 on: Today at 04:40:04 PM »
   
Summary of AG6K's tube arc proof in a 4-1000 amplifier:

1.) There is aurora

2.)  Gas filled HV Geiger-Muller tubes occasionally have a few microampere "tic" when exposed to room radiation

3.) A Prius computer occasionally locks up

4.) Someone said a spectrum analyzer shows a 100MHz pulse when an SB220's relay is rapidly keyed off and on with shorted input and output ports and a probe inches from the anode

5.) A bell does not ring in a vacuum

6.) Sue's dog is a red herring

  where's the proof  that I said the tube arced?


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on October 31, 2011, 05:37:21 PM
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AF6LJ
Susan
   
RE: Background Radiation - Could It Be a Vexation ?
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2E0CHE
   
RE: Background Radiation - Could It Be a Vexation ?
« Reply #92 on: Today at 01:56:44 PM »
   
But nowhere near enough to be in any way significant without gas to provide for avalanche breakdown.... ... ... ..

  One more time:  Hello,   There is no breakdown or arc inside the tube.  The tube briefly conducts, rings the anode-circuit's parasitic VHF resonance, which makes a damped wave VHF signal - which is than amplified and re-amplified until things largely run amok because VHF energy can not pass through the LowPass Pi-tank to reach the load.
Rich, ag6k

...
This can't happen if the amplifier is sitting idle,


  so electrons can Not be knocked loose from a Mo grid when there is HV present and the amp is in standby?

 
Quote
it can't even happen in a properly designed amplifier[/quote

 chortle.  This is what one of our "recognized amplifier experts" told me about VHF parasites but he could not explain what was proper and what was not. 

Quote
There isn't going to be enough electrons dislodged by some cosmic ray, or high energy photon

  why not?

.
Quote
If this could even happen, how do you think we would have made it to the moon and back as many times as we did?

  Because there were no whopper solar flares or any gamma-ray bursts from a supernova during any moon mission.

Quote
There is nowhere on the net I can find any documentation for this ever occurring.
Nobody has written any papers on this.

Your Geiger tube does it because there is a large bias on the electrodes

  My Geiger-Muller tube runs on 900vdc.  Said 4-1000A runs on 5000vdc.

Quote
and the gas inside is at a rather low pressure.

  can electrons only be knocked loose from gasses?
Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AF6LJ on October 31, 2011, 09:19:01 PM
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AF6LJ
Susan
   
RE: Background Radiation - Could It Be a Vexation ?
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Quote from: AG6K on Today at 02:34:59 PM
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2E0CHE
   
RE: Background Radiation - Could It Be a Vexation ?
« Reply #92 on: Today at 01:56:44 PM »
   
But nowhere near enough to be in any way significant without gas to provide for avalanche breakdown.... ... ... ..

  One more time:  Hello,   There is no breakdown or arc inside the tube.  The tube briefly conducts, rings the anode-circuit's parasitic VHF resonance, which makes a damped wave VHF signal - which is than amplified and re-amplified until things largely run amok because VHF energy can not pass through the LowPass Pi-tank to reach the load.
Rich, ag6k

...
This can't happen if the amplifier is sitting idle,


  so electrons can Not be knocked loose from a Mo grid when there is HV present and the amp is in standby?

Not by such a small and low energy source.
Sorry Rich it's not happening, it's not happening with a copper anode and it's certainly not happening with glass or ceramic insulator material.
If it ever does you and I won't be alive to see it.


From where did you learn physics?
 


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on November 01, 2011, 02:09:37 AM
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Quote from: AG6K on Yesterday at 05:37:21 PM
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AF6LJ
Susan
   
RE: Background Radiation - Could It Be a Vexation ?
« Reply #94 on: Today at 03:06:53 PM »
   
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Quote from: AG6K on Today at 02:34:59 PM
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2E0CHE
   
RE: Background Radiation - Could It Be a Vexation ?
« Reply #92 on: Today at 01:56:44 PM »
   
Quote
But nowhere near enough to be in any way significant without gas to provide for avalanche breakdown.... ... ... ..

Quote
  One more time:  Hello,   There is no breakdown or arc inside the tube.  The tube briefly conducts, rings the anode-circuit's parasitic VHF resonance, which makes a damped wave VHF signal - which is than amplified and re-amplified until things largely run amok because VHF energy can not pass through the LowPass Pi-tank to reach the load.
Rich, ag6k
...
Quote
This can't happen if the amplifier is sitting idle,


Quote
  so electrons can Not be knocked loose from a Mo grid when there is HV present and the amp is in standby?


Quote
Not by such a small and low energy source.

  what is the source Susan?

Quote
Sorry Rich it's not happening, it's not happening with a copper anode and it's certainly not happening with glass or ceramic insulator material.

  so the electrons in some elements are stuck better than the electrons in other elements?  Hmmmm.  Very interesting.

Quote
If it ever does you and I won't be alive to see it.

Quote
From where did you learn physics?

  When running low on ammo, attack the CV. 

cheers Susan
Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: G3RZP on November 01, 2011, 04:52:06 AM
If the tube is biased off, how can it have any gain to amplify the VHF signal pulse? Ergo, unless the pulse has suffisient energy to cause the damage, the tube can't amplify enough to do it.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AF6LJ on November 01, 2011, 06:21:15 AM
If the tube is biased off, how can it have any gain to amplify the VHF signal pulse? Ergo, unless the pulse has suffisient energy to cause the damage, the tube can't amplify enough to do it.

I think what Rich is failing to understand is there must be a complete circuit for current to flow regardless of energy of the external source (photons, gamma rays X-Rays etc.).

Question for Rich;
How much energy is required to knock electrons loose from Glass?
How much energy is needed to knock electrons loose from Copper?
And finally have you ever seen glass ionize from cosmic rays or any other high energy radiation?

Lastly;
I was not attacking your CV I just asked a question, Please don't take it personally. My own CV isn't anything to brag about. I'll freely admit my knowledge of high energy physics comes from books and simplified discussions on the subject.



Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on November 01, 2011, 07:46:40 AM

RE: Background Radiation - Could It Be a Vexation ?
« Reply #100 on: Today at 04:52:06 AM »
   
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If the tube is biased off, how can it have any gain to amplify the VHF signal pulse? Ergo, unless the pulse has suffisient energy to cause the damage, the tube can't amplify enough to do it.

  No current is required to overcome the cutoff bias-V and cause anode-I to flow.  When anode-I flows, thanks to the feedback-C, the tube can amplify and re-amplify the damped-wave signal . When the tube conducts, the cathode bias relay contacts can arc, major current can then flow, followed by the fireworks show.
Rich, ag6k   


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: M0HCN on November 01, 2011, 07:54:17 AM
Well you can knock electrons loose from all those materials, the key phrase is 'work function', but so what, a few dozen, or even a few hundred electrons is an utterly negligible amount of current in this context, and even when accelerated across a few KV, does not amount to a meaningful amount of energy compared to that stored in the tank circuit in normal operation (or even that in the VHF resonance in normal operation).

The grid has capacitance, ergo current MUST flow to change the grid voltage, dV=dQ/C. I have already demonstrated that the grid capacitance is large enough to make the charge on any reasonable number of photoelectrons that could be freed utterly irrelevant.

Further in standby the tube is biased well off, the grid would have to become quite a lot more positive to allow gain, and would have to stay there for long enough for oscillation to build up. If the amp was unstable at VHF it would show in normal transmit mode way before the instability got sufficiently severe (I don't think it could) to show with the tube based off.

I am out of here.

73 Dan.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: G3RZP on November 01, 2011, 09:07:10 AM
So we have a very small current that now manages to get enough energy to turn the tube on and produce an arc?

Sorry, Rich, this is mere fantasy. The evidence just doesn't hold up.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on November 01, 2011, 09:34:05 AM
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G3RZP
RE: Background Radiation - Could It Be a Vexation ?
« Reply #104 on: Today at 09:07:10 AM »
   
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So we have a very small current that now manages to get enough energy to turn the tube on and produce an arc?

  The tube does not arc Peter, the tube briefly conducts. The pulse of I rings the VHF-resonant circuit between the anode-C and the Tune-C producing a damped wave VHF signal that gets fed back to the input and amplified provided that the tube has sufficient VHF-gain.  Sometimes fireworks ensue - but Not inside the electron tube.   
Rich, ag6k

Quote
Sorry, Rich, this is mere fantasy. The evidence just doesn't hold up.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: G3RZP on November 01, 2011, 12:33:36 PM
But Rich, you started with the tube cut off. So how does it have gain? The few electrons aren't enough of a current pulse so it NEVER turns on.

Which is why I say this theory is no better than fantasy.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on November 01, 2011, 03:42:28 PM
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G3RZP

RE: Background Radiation - Could It Be a Vexation ?
« Reply #106 on: Today at 12:33:36 PM »
   
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But Rich, you started with the tube cut off. So how does it have gain?

  by I-flow.

 
Quote
The few electrons aren't enough of a current pulse so it NEVER turns on

  How do you know how many electrons were liberated by high energy photons colliding with atoms inside the tube Peter ?

.
Quote
Which is why I say this theory is no better than fantasy.

  If it's undiluted fantasy why do 3-500Zs and 3-400Zs often prove have bent filament helicies after a big bang, and why do parasitic suppressor resistors change value by several x after a big bang - and without showing any sign of overheating?
Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: M0HCN on November 01, 2011, 04:10:29 PM
Rich, what are the voltage ratings on those anti parasitic resistors?

Having a resistor go high when hit with a voltage transient many times its rating is not exactly unheard of,  and for that matter, these things usually have maximum pulse energy ratings that may have little to do with bulk thermal effects. Look at all the bleeder resistors that turn out to be open all too often for another example of the effect of exceeding resistor voltage ratings.

Bent filament structures sound like magnetic fields to me, which I would read as a tube solidly into conduction (Think gassy), not the sort of thing a few e- (which is all you are going to get from a gamma photon) could cause. 

A sufficiently fast glitch event can produce LOTS of dI/dT which means lots of volts across those resistors, no surprise they suffer, this is not normal operation, and lots of amps flowing in the electrode structure will produce significant magnetic forces that I could entirely see bending electrode structures.

If YOU want to propose an extraordinary mechanism for something, it behoves YOU to show that the math works, which so far you have singularly failed to do. Just an orders of magnitude calculation would do.

Regards, Dan.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: W7SMJ on November 01, 2011, 04:12:57 PM
AG6K, why not borrow an x-ray machine and bombard your amp of choice while it is idle?  Would that not prove or disprove your theory?

73,
Scott


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on November 01, 2011, 10:00:07 PM
Quote
W7SMJ

RE: Background Radiation - Could It Be a Vexation ?
« Reply #109 on: Today at 04:12:57 PM »
   
AG6K, why not borrow an x-ray machine and bombard your amp of choice while it is idle?  Would that not prove or disprove your theory?

73,
Scott

  An x-ray machine may or may not do an encore Scott since I have no idea of what type of high-energy radiation caused the 4-1000A amplifier in Idaho to conduct and have the event.  If it was a gamma-ray that caused current-flow, then an x-ray machine will not prove anything.  If it was a cosmic-ray that caused the 4-1000A to conduct, then renting a gamma-ray generator would be $$ in the crapper. 
  I don't need to play the blame game with skeptics because, after such events,  I have tested enough kaput VHF parasitic suppressor resistors, and I have autopsied enough filament to grid shorted 3-400Zs and 3-500Zs with bent filament helices to realize that something out of the ordinary is happening here.
  The present evidence:  The surviving 4-1000A is healthy, not gassy -- but something caused it to suddenly conduct and tank voltages to temporarily run amok.
   During the Grate Parasitics Debate Mr. Rauch insisted that the reason the tubes from amplifiers that made out of the blue big-bangs subsequently exhibited no signs of being gassy was because the hot filament getters the gas before the amplifier can be shut down and the high-pot tester is fired up.  When I mentioned that the gettering agent is on the anode and not on the filament, it didn't seem to matter. Also, the electric alarm bell in the evacuated bell-jar experiment doesn't matter and the sudden, large change in R-supp doesn't matter either.
cheers Scott
Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on November 01, 2011, 10:52:03 PM
Quote
2E0CHE
   
RE: Background Radiation - Could It Be a Vexation ?
« Reply #108 on: Today at 04:10:29 PM »
   
Reply with quoteQuote
Rich, what are the voltage ratings on those anti parasitic resistors?

  There is no V-rating on such resistors, they have a max dissipation in watts rating at 70ºC. 

Quote
Having a resistor go high when hit with a voltage transient many times its rating is not exactly unheard of,

   Correct Dan and I'm pretty sure too much V zaps the R-supps.  However, R-supps are typically paralleled by 0.001 to 0.002 ohms of coiled Cu wire which has an L of 60 to 100 nanoHenrys.- and that should tell us that the potential that torpedoed R-supp was not DC or HF - but VHF.

 
Quote
and for that matter, these things usually have maximum pulse energy ratings that may have little to do with bulk thermal effects. Look at all the bleeder resistors that turn out to be open all too often for another example of the effect of exceeding resistor voltage ratings.

Bent filament structures sound like magnetic fields to me, which I would read as a tube solidly into conduction (Think gassy),

  I agree on electro-magnetism being responsible for pushing hot filament helices sideways to the flow of current. However, tubes that exhibit filament to grid shorts when the filament is hot usually have no unusual amount of leakage-I when 2x the rated max anode-V is subsequently applied with a high-potential tester. 

Quote
not the sort of thing a few e- (which is all you are going to get from a gamma photon) could cause.

  how did you count the # of  gamma-ray photons that struck the 4-1000A in Idaho ?

Quote
A sufficiently fast glitch event can produce LOTS of dI/dT which means lots of volts across those resistors,


  but only if the paralleled  .001 to 0.002 ohm  L-supp is removed.

Quote
no surprise they suffer, this is not normal operation, and lots of amps flowing in the electrode structure will produce significant magnetic forces that I could entirely see bending electrode structures.

If YOU want to propose an extraordinary mechanism for something, it behoves YOU to show that the math works, which so far you have singularly failed to do. Just an orders of magnitude calculation would do.

Regards, Dan.

  Math is only possible when we know all of the numbers at the instant of the big-bang, and we do not.  so we go with the circumstantial evidence.   However, for those groupies who believe that an electric alarm bell can be heard without attenuation in an evacuated bell-jar, no evidence can ever suffice. 
cheers Dan
Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: W8JI on November 02, 2011, 01:40:44 AM
This is an example how the ARRL and others get into trouble by printing or passing along technical gibberish or fantasia.

Not only is the photon instigated arc stuff all nonsense, and the parasitic damage stuff nonsense, now we have the force on filaments.

If you run the math on the filament, using the SATURATED plate current emission limits of the tubes, you will see the force on the filament is in the order of a few grams! Without an exceptionally hard arc of hundreds of amperes caused by gas, forces are negligable. Even with gas, bending from magnetic force is unlikely. 

All of this stuff is just far fetched fantasy designed to sell nichrome suppressors. Everything and everywhere this stuff comes up, masses of people point out all the flaws. Every single bit of the fantasy stuff is designed to sell nichrome kits, the cure for every single failure.

When the ARRL sent out the author's Handbook article and his other articles to dozens of people who were experts in various areas, every single reviewer (both inside and outside the Amateur fraternity) came back saying it was nonsense. Not one single response was positive.

73 Tom


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on November 02, 2011, 06:18:55 AM
Quote
  Tom Rauch W8JI:  This is an example how the ARRL and others get into trouble by printing or passing along technical gibberish or fantasia.

Not only is the photon instigated arc stuff all nonsense, and the parasitic damage stuff nonsense, now we have the force on filaments.

  After the 2nd of the three articles on VHF parasitic oscillation was published in QST Magazine, Mr. Rauch telephoned me to discuss the subject.  During the course of our conversation he stated that he had been involved in repairing 400 Heath SB-220 amplifiers and that many of them had damage from VHF parasitic oscillations.  .  .  What goes around comes around.
Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on November 02, 2011, 09:26:28 AM
Quote
Tom Rauch, W8JI: ... ... ... When the ARRL sent out the author's Handbook article and his other articles to dozens of people who were experts in various areas, every single reviewer (both inside and outside the Amateur fraternity) came back saying it was nonsense. Not one single response was positive.

73 Tom

  the "nonsense":
http://www.somis.org/D-amplifiers1.html
http://www.somis.org/D-amplifiers2.html
http://www.somis.org/D-amplifiers3.html
http://www.somis.org/D-amplifiers4.html
Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: KF7CG on November 02, 2011, 10:29:08 AM
Having worked with x-ray analysis equipment, I nkoe that it takes at least 1kev of energy to remove one electron from aluminum and appoximately 50 kev for copper and silver. With no avalanche media to be triggered by stray radiation it would take quite a few energetic particles to generate anything that looked like a current.

I do not wish to speculate on effects this is just a good data point around which to work. Also, add to this that typical particle to ejected electron efficiency is less than 10%.

KF7CG


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: KB8E on November 02, 2011, 11:11:58 AM
Ah yes, the thread that never ends! Actually, this thread is disturbing to me. The original poster asked a question and solicited a variety of responses. However, he then argued with the respondents and the subject seemed to change to something like pulse-excited VHF oscillations in linear HF amplifiers, something the poster seems to feel strongly about. I have to conclude that the author had no intention of actually considering responses to the original post, just provoke an argument. I'm guessing that he has a particular person in mind and wants to argue with that person and all those who agree with him. Forums should be about the open exchange of information and ideas, not a place to pick a fight with the forum ‘experts’. Sure the ‘experts’ may be wrong, at least some of the time, but in my reading of their posts, I have to say that they should be taken very seriously. I've seen some good analytical physics and electrical engineering ideas posted by the experts and in addition, one should not dismiss the writings of a person who is the go-to guy in the amplifier industry.

Intelligent people can disagree, but some of the writings here border on pseudoscience. Kind of like the guy who claims that sidebands aren't necessary to carry information.

Sam


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: KM3F on November 02, 2011, 05:20:34 PM
AMEN Sam,
Thought this a long time ago.
Advise not to even respond to such pervokeings becaue there is no ending to it unless everybody just stops.
The next time such a throught pervokeing subject is posted' let it alone.
If such a radiation permotes an out of control action, a lot of gas filled tubes would be fireing but they don't.
When was the last time you saw a NEON sign flashing when the anode voltage was below the ignition point?
I have built gas filled noise sources for microwave use in space shots. They don't fire in space just because there is Cosmic radiation.

Ken.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on November 02, 2011, 05:20:51 PM
Quote
KB8E
   
RE: Background Radiation - Could It Be a Vexation ?
« Reply #116 on: Today at 11:11:58 AM »

Ah yes, the thread that never ends! Actually, this thread is disturbing to me.

  You have company.  The idea that things unseen, unsmelt and unfelt can affect our lives is disturbing.  However, since high-energy photons can change DNA sequences they are the major source of genetic mutations.  

Quote
The original poster asked a question and solicited a variety of responses. However, he then argued with the respondents and the subject seemed to change to something like pulse-excited VHF oscillations in linear HF amplifiers, something the poster seems to feel strongly about.

  Damped wave ringing is an integral part of parasitic oscillation since it is the seed that sprouts into the phenomenon.  

Quote
I have to conclude that the author had no intention of actually considering responses to the original post, just provoke an argument.

  Correct.  I have seen enough evidence on my Geiger-counter and in the analysis of damaged amplifiers that sustained an event on Standby to convince me that such a thing is not impossible.   However, I came to this conclusion only after the 3 articles on parasites were published in QST.

Quote
I'm guessing that he has a particular person in mind and wants to argue with that person and all those who agree with him.


  If you are talking about one of our recognized experts and his faithful groupies, he is almost as defiant as Ramses the Great and  he will likely never agree with me on even the day of the week.

Quote
Forums should be about the open exchange of information and ideas, not a place to pick a fight with the forum ‘experts’. Sure the ‘experts’ may be wrong, at least some of the time, but in my reading of their posts, I have to say that they should be taken very seriously. I've seen some good analytical physics and electrical engineering ideas posted by the experts and in addition, one should not dismiss the writings of a person who is the go-to guy in the amplifier industry.

  One prominent "expert" certainly gets some things right, but he also professes things that aren't.  Example:
Do you see anything questionable about the statement that Ni-Cr alloy conductors exhibit reverse
RF skin-effect?  How about dipmeters give false information?
[/quote]
Quote
Intelligent people can disagree, but some of the writings here border on pseudoscience. Kind of like the guy who claims that sidebands aren't necessary to carry information.

Sam
[/quote]
  A-Zero emissions carriy the info that the operator is somewhat retarded - yet there are no sidebands Sam.  cheers


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: N4MPM on November 03, 2011, 01:45:31 AM
The Pig is happy.  Keep wrestling!  Nothing stands in the way of true love. ::)


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: G3RZP on November 03, 2011, 02:27:25 AM
Sam,

Back in the late 1920s, a lot of very eminent men argued about the existence of sidebands, even though there had been a transatlantic SSB link since 1926 on about 60 kHz. It even led to a UK government research report on it - when that came out in about 1932 (!) the argument was long over.

Just a bit of irrelevant information, but that's not out of place on this thread.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on November 03, 2011, 02:56:29 AM
Quote
G3RZP
   
RE: Background Radiation - Could It Be a Vexation ?
« Reply #120 on: Today at 02:27:25 AM »
   
Reply with quoteQuote
Sam,

Back in the late 1920s, a lot of very eminent men argued about the existence of sidebands, even though there had been a transatlantic SSB link since 1926 on about 60 kHz. It even led to a UK government research report on it - when that came out in about 1932 (!) the argument was long over.

Just a bit of irrelevant information, but that's not out of place on this thread.

  Good one Peter C.  I had no idea that this alpha-male head-butt started that far back.    Curiously, there were also some very eminent men who stentorianly ridiculed Rudolph Diesel's compression-ignition, goober-oil burning engine when it came out in 1893. 
cheers
Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AF6LJ on November 03, 2011, 05:40:04 AM
Just walk away;
there comes a point in the defense of a theory when all reasoned and logical discussion fails to prop up a theory in the absence of physical evidence. As a former electronics technician of twenty one years; you can spout arcane theories all day, (or until the cows come home whichever you prefer) but if you don't have a shred of physical evidence it doesn't contribute to the advancement of the state of the art let alone get the amplifier fixed.

To continue to argue the point without designing an experiment to test the theory or to explore other possibilities. is counterproductive and a detriment to one's credibility.  

I have read reams of articles and complaints about instability in Heath SB-220s and Kenwood TL-922s, funny thing you don't hear L-4B or Swan Mark Two owners complaining, do you?
They all use the same tubes, seems like the Drake and Swan designs are good stable designs and the Heath and Kenwood designs are crap.

Why not address the actual problem instead of making a name on some theory that belongs on Coast to Coast AM?
 


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on November 03, 2011, 04:44:04 PM
Quote
AF6LJ,    Susan
RE: Background Radiation - Could It Be a Vexation ?
« Reply #122 on: Today at 05:40:04 AM »
   
Reply
Just walk away;
there comes a point in the defense of a theory when all reasoned and logical discussion fails to prop up a theory in the absence of physical evidence. As a former electronics technician of twenty one years; you can spout arcane theories all day, (or until the cows come home whichever you prefer) but if you don't have a shred of physical evidence

  The evidence:
1.  Sound waves do not travel well in a vacuum so the arc is not inside the vacuum tube as Tom R. asserts.
3.  Tubes that filament-grid short during a big bang do not test gassy - so it's not the tube.
4.  The sudden change in R-supp during the big bang can not be explained by HF energy because R-supp is paralleled by a low inductance.
5.  high-energy photons are known to be able to bounce electrons.   Example: In a florescent lamp, UV photons from ionized Hg vapour strike P atoms, bounce electrons to a higher orbit, and when the electrons fall back to their original orbit they emit light. 

Quote
it doesn't contribute to the advancement of the state of the art let alone get the amplifier fixed

  One must first realize that the problem was not a gassy tube in order to get the problem of too much VHF amplification fixed.

.
Quote
To continue to argue the point without designing an experiment to test the theory or to explore other possibilities. is counterproductive and a detriment to one's credibility.
 

  So tell  us what other possibilities are Susan.

Quote
I have read reams of articles and complaints about instability in Heath SB-220s and Kenwood TL-922s, funny thing you don't hear L-4B or Swan Mark Two owners complaining, do you?

  I certainly do since L4B owners still order suppressor retrofit kits .  The L4B  does not have as much of a problem because it does have as much HV - which means it does not have as much VHF-amplification - which means it has less chance of VHF oscillation.  .

Quote
They all use the same tubes, seems like the Drake and Swan designs are good stable designs and the Heath and Kenwood designs are crap.

Why not address the actual problem.
 


  The actual problem is not reducing VHF amplification enough to obviate VHF oscillation.  . 

Quote
instead of making a name on some theory that belongs on Coast to Coast AM?

Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AF6LJ on November 04, 2011, 07:32:25 AM
Your logic Rich is based on circumstantial deviance and isn't supported by real world experience.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: W8JI on November 04, 2011, 07:49:25 AM
Your logic Rich is based on circumstantial deviance and isn't supported by real world experience.

Logical thought and facing the truth will not sell suppressor kits.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: N0YXB on November 04, 2011, 08:08:01 AM
After reading this thread I have decided to go public with my dilithium crystal suppressor kit.  Tired of cosmic rays causing your amplifier tubes to arc?  Well, you need to buy my dilithium crystal suppressor kits.  Dilithium cannot be found on the earth, but thanks to a time travelling Starfleet officer, I have enough to manufacture and sell high efficiency dilithium crystal suppressors.  For greatest effect, you'll need three of my suppressors, one that handles Newtonian physics, one for Quantum physics, and one for the new physics described to me by the wayward Starfleet officer.  Order now, supplies are limited!  Of course these suppressors are very expensive due to the rarity of dilithium crystals.

I could not resist.   ;)

73.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: W8JI on November 04, 2011, 09:05:58 AM
The entire thing about parasitics is just bizarre.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on November 04, 2011, 09:24:30 AM
Quote
AF6LJ
Susan

RE: Background Radiation - Could It Be a Vexation ?
« Reply #124 on: Today at 07:32:25 AM »
   
Reply with quoteQuote
Your logic Rich is based on circumstantial deviance and isn't supported by real world experience.

 My logic is based on what I learned in Physics classes, Electronic Engineering classes, the experience of repairing amplifiers that sustained big bangs and  what I learned from autopsying kaput 3-400Zs, 3-500Zs, 8874s, 8875s, and 8877s. 
  The most surprising thing to me about this thread is that so many of the skeptics did not understand what I wrote even after multiple repeats.  Looking back, what I should have done was to first ask how many people believe that sound waves can travel in a vacuum, and the go from there.
  The funniest part about this thread is that some of the most vociferous skeptics lived in areas where they could see the spectacular  1,000,000-Ampere + N2/red aurora, yet they had no trouble expertly professing that it was absolutely impossible for higher-energy photons to cause current flow.

Laughter really is the best medicine.
Rich, ag6k
... and Susan, how about proposing your alternate theory?


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AF6LJ on November 04, 2011, 10:38:08 AM
Quote
AF6LJ
Susan

RE: Background Radiation - Could It Be a Vexation ?
« Reply #124 on: Today at 07:32:25 AM »
   
Reply with quoteQuote
Your logic Rich is based on circumstantial deviance and isn't supported by real world experience.

 My logic is based on what I learned in Physics classes, Electronic Engineering classes, the experience of repairing amplifiers that sustained big bangs and  what I learned from autopsying kaput 3-400Zs, 3-500Zs, 8874s, 8875s, and 8877s. 
  The most surprising thing to me about this thread is that so many of the skeptics did not understand what I wrote even after multiple repeats.  Looking back, what I should have done was to first ask how many people believe that sound waves can travel in a vacuum, and the go from there.
  The funniest part about this thread is that some of the most vociferous skeptics lived in areas where they could see the spectacular  1,000,000-Ampere + N2/red aurora, yet they had no trouble expertly professing that it was absolutely impossible for higher-energy photons to cause current flow.

Laughter really is the best medicine.
Rich, ag6k
... and Susan, how about proposing your alternate theory?
My alternate theory is the design of the amplifier is at fault.
There are more crap designs than good designs. I would also add that bad tubes get built sometimes with virtual leaks. (contaminated materials that outgas into the vacuum over time).

You have not provided any documentation on what happens during this "big bang" and what I mean by documentation are meter readings or any way to repeat the failure mode. You make a religious leap of faith based on not being able to find another cause.

Google "Effects of high energy particles on vacuum tube operation" and see what you come up with, nothing, zipp, nadda....

Show me just one peer reviewed paper that supports your failure mode.

If what you say actually dose happen it would have been reported in the semiconductor industry decades ago when they first began ion implantation, a big bang like that could cause tens of thousands even  hundreds of thousands of dollars in damage to implantation equipment.
The same level of damage would be happening to ion discharge milling equipment.

If you have had the physics then you know one high energy particle or even a few hundred won't do what you are claiming happened. A million amps of aurora is distributed over several tens to hundreds of cubic miles in the upper atmosphere.

I respectfully submit the science and the logic just isn't there.
Show me the peer reviewed papers and I'll gladly change my mind. If I have sufficient proof I will believe anything no matter how strange it may appear.



Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: W8JI on November 04, 2011, 12:08:30 PM
The amplifier forum has become like the Twilight Zone in the past few weeks, or like a trip through the looking glass.  This is 9 pages to discuss some of the worse science fiction yet.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: G3RZP on November 04, 2011, 12:23:21 PM
Tom,

some 40 odd years ago, there was a string of quite amusing short SF stories about a character called Fritz van Noon and the Unconventional Engineers, who toured the galaxy dealing with strange things. One of those stories had a set of glowing mountains because the mountains had layers of gallium and arsenic, with iron veins: rotation around a double sun induced enough current to light up the layers of gallium and arsenic as giant LEDs.

The cosmic ray induced arc triggering VHF parasitics falls, in my book, to not quite as inventive pseudo science fiction as that.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: W8JI on November 04, 2011, 12:36:10 PM
Tom,

some 40 odd years ago, there was a string of quite amusing short SF stories about a character called Fritz van Noon and the Unconventional Engineers, who toured the galaxy dealing with strange things. One of those stories had a set of glowing mountains because the mountains had layers of gallium and arsenic, with iron veins: rotation around a double sun induced enough current to light up the layers of gallium and arsenic as giant LEDs.

The cosmic ray induced arc triggering VHF parasitics falls, in my book, to not quite as inventive pseudo science fiction as that.

Peter,

This stuff has been going on for years. Not one other person experienced in HF PA's or vacuum tubes has ever agreed with any of it. When the ARRL sent articles out for review dozens of people, from Rockwell through every other notable place, all came back saying it was pure fiction. There is no amount of talking sense, or science, or evidence that can ever change any of this.

The damage this nonsense does to people trying to learn goes far beyond what appears on the surface. The recent, very bad tube filament voltage article from QST was rooted in this same source of psuedo-science. It's probably the single worse thing that has happened to our hobby's technology base in years.

This, and the nichrome low Q stuff, was just a small sample of the nonsense pile.

73 Tom


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: G3RZP on November 04, 2011, 03:12:12 PM
Tom,

I feel that in this respect, the RSGB are, for once, ahead of ARRL. The majority of technical articles get offered by email to a fairly large committee for volunteers - more than one - to review. On the odd occasion that the first two volunteer reviewers don't agree (once in more than five years!), two external reviewers are called in. The only time this happened, we had one reviewer in favour and four against.......thumbs down! If the article is acceptable but it is felt changes are needed, the lead reviewer works with the author to get the article acceptable. In a number of cases where the author is a non native English speaker, this can mean a fairly major re-write, which the reviewer does - gratis, I may say. The author gets the cash - the reviewer has 'the gratifying feeling that our duty has been done' - Gilbert & Sullivan, the Mikado.
 


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on November 04, 2011, 03:29:36 PM
Quote
W8JI, Tom Rauch
Peter,

This stuff has been going on for years. Not one other person experienced in HF PA's or vacuum tubes has ever agreed with any of it.

  When Tom Rauch, W8JI telephoned me after the 2nd QST Magazine article on parasites was published he told me that most of the 400 SB-220 amplifiers he had repaired had signs of VHF parasitic damage. 

Quote
When the ARRL sent articles out for review dozens of people, from Rockwell through every other notable place, all came back saying it was pure fiction.
  Is it pure fiction that each 3% increase in Th-W filament potential cuts emissive life by half?
Quote
>There is no amount of talking sense,

  Does it make sense that dipmeters can not find parasitic resonances?

Quote
or science, or evidence that can ever change any of this.

The damage this nonsense does to people trying to learn goes far beyond what appears on the surface. The recent, very bad tube filament voltage article from QST was rooted in this same source of psuedo-science. It's probably the single worse thing that has happened to our hobby's technology base in years.

This, and the nichrome low Q stuff, was just a small sample of the nonsense pile.
73 Tom[

  “The combination of both resistance and inductance is very effective in limiting parasitic oscillations to a negligible value of current.”
- -  F. E. Handy, W1BDI    1926 Ed.  The Radio Amateur's Handbook,  p. 72,
••  Is  this info obsolete as some of our "experts" have professed?.  Has Ohm's law changed ?
Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AF6LJ on November 04, 2011, 03:46:46 PM
I have been around long enough to know that every field has their cults and their cult followers. The only good that can come from exchanges like this is to wake up and educate people. Vacuum tube tech is over a hundred years old. Everything there is to know about them is in print, all factual and all scientifically based and all solidly referenced. There are no magic bullets, or God Particles that can slam an amplifier out of cutoff, or just idling and into oscillation dampened or otherwise. One would even be challenged to make this happen in a poorly designed amplifier if it didn't oscillate when the B+ was applied.

There was one other man so invested in his theories that he ended up being laughed at by his peers but Immanuel Velikovsky, at least wrote three books that were good fiction if nothing else. The ideas presented here are not even good fiction, they have to work within the laws of the physical universe to be considered good fiction.

Misinformation is a bad thing, worse yet are those who perpetuate it without consideration for the facts.

What originally brought me here was the October QST article after considerable discussion over on QRZ.com I had to see what had transpired over here since I know a few who post here often. It seems I have found the headwaters from which the river I have followed originate.

Reality never ceases to amaze me, as long as I live and no matter how much pain I have to endure (and I know from what I speak) I will always go to sleep in anticipation of what the next day brings like a little girl on Christmas eve.


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on November 04, 2011, 03:58:34 PM
Quote
AF6LJ, Susan
My alternate theory is the design of the amplifier is at fault.

  Alternate?  I've repeatedly been preaching that the design fault is that VHF amplification has not been reduced enough to avoid regeneration. 

Quote
There are more crap designs than good designs. I would also add that bad tubes get built sometimes with virtual leaks. (contaminated materials that outgas into the vacuum over time).

  The  majority of the tubes I tested after a big-bang had good vacuums.

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You have not provided any documentation on what happens during this "big bang"

  One of the QST Staffers and I brainstormed on the elapsed time for a push-push parasitic big bang and we concluded that it's over in c. 100uSec for a 3-400Z or 3-500Z.  Who can take notes that fast?

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and what I mean by documentation are meter readings or any way to repeat the failure mode. You make a religious leap of faith based on not being able to find another cause.

  There can not be more than one.


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Google "Effects of high energy particles on vacuum tube operation" and see what you come up with, nothing, zipp, nadda....

  I Googled parasitic oscillation and I got 607,000 hits. 

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Show me just one peer reviewed paper that supports your failure mode

  stop by sometime and you can help me autopsy a 3-400Z that fil/grid shorted during a big-bang and you can see for yourself Susan.

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If what you say actually dose happen it would have been reported in the semiconductor industry decades ago when they first began ion implantation, a big bang like that could cause tens of thousands even  hundreds of thousands of dollars in damage to implantation equipment.
The same level of damage would be happening to ion discharge milling equipment.

If you have had the physics then you know one high energy particle or even a few hundred won't do what you are claiming happened. A million amps of aurora is distributed over several tens to hundreds of cubic miles in the upper atmosphere.

I respectfully submit the science and the logic just isn't there.
Show me the peer reviewed papers and I'll gladly change my mind. If I have sufficient proof I will believe anything no matter how strange it may appear.

  No alternate theory.

Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on November 07, 2011, 01:49:23 AM
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Ignore
   
   
RE: Background Radiation - Could It Be a Vexation ?
« Reply #125 on: November 04, 2011, 07:49:25 AM »
   
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Quote from: AF6LJ on November 04, 2011, 07:32:25 AM
Your logic Rich is based on circumstantial deviance and isn't supported by real world experience.

Logical thought and facing the truth will not sell suppressor kits. Tom Rauch W8JI

   Tom R.:  Since the time that you told me you had repaired hundreds of SB-220s with VHF parasitic osc. damage, we have sold c. 10,000 lower VHF-Q parasitic suppressor retrofit kits.  I made no profit on these  because I pay my helpers a fair wage.   This has the benefit of reducing turnover.  My current helper is 24 and she has been doing mail orders since she was 11. 
  The reason we are still selling retrofit kits is because they decrease VHF amplification, which decreases the chance of VHF oscillation.  The trade-off is that they decrease P-output at 28MHz by about 1/11 of an S-unit. 
Rich, ag6k


Title: RE: Background Radiation - Could It Be a Vexation ?
Post by: AG6K on November 07, 2011, 03:13:35 AM
I have been around long enough to know that every field has their cults and their cult followers. The only good that can come from exchanges like this is to wake up and educate people.

  bull's-eye, 10-points for Susan.

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Vacuum tube tech is over a hundred years old. Everything there is to know about them is in print, all factual and all scientifically based and all solidly referenced. There are no magic bullets, or God Particles that can slam an amplifier out of cutoff, or just idling and into oscillation dampened or otherwise.

  Correct.  Any mechanism or rapid sequence of events that causes gold to evaporate from the grid of an $800 8877 has for damn sure got to be from the mo-fo Devil Himself.

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One would even be challenged to make this happen in a poorly designed amplifier if it didn't oscillate when the B+ was applied.

   Applying +HV to the anode will not in itself case a parasitic osc. because it takes an anode current pulse to ring the VHF parasitic resonance and create the VHF signal that can lead to VHF oscillation -- provided the stage has enough VHF-amplification to support regeneration.
   Feedback-C is a given.  There is no real-special esoteric layout or voodoo incantation that will cancel C-fb Susan.  Of course, feedback-C is smallish, being only 0.6pF in an 811A or 572B and 0.1pF in an 8877, however at VHF feedback's XC is not inconsiderable.  Example:  the SB-220's parasitic-resonance is 110MHz.  Two 3-500Zs have 0.3pF of C-fb, which is –j4300-ohms at 110MHz.  As I see it 4300-ohms of feedback at the parasitic-resonance should probably not be ignored.

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There was one other man so invested in his theories that he ended up being laughed at by his peers but Immanuel Velikovsky, at least wrote three books that were good fiction if nothing else. The ideas presented here are not even good fiction, they have to work within the laws of the physical universe to be considered good fiction.

Misinformation is a bad thing, worse yet are those who perpetuate it without consideration for the facts.

What originally brought me here was the October QST article after considerable discussion over on QRZ.com I had to see what had transpired over here since I know a few who post here often. It seems I have found the headwaters from which the river I have followed originate.

  A  laugher about the original Oct. 1988 article:  A celeb owner of a TenTec amplifier who had no success in keeping his TenTec amplifier from arcing and sparking from what appeared to be intermittent parasitic oscillations - even after he had sent it to TenTec twice to have the problem fixed, tried reducing the Q of the VHF suppressors.  Eureka, the arcing and sparking stopped,  so he wrote a letter to TenTec giving them the good news.  TenTec wrote back saying they read the Oct. 1988 QST article, tried using lower VHF-Q suppressors, but abandoned the idea when they discovered that the new VHF (30-300 MHz) suppressors got very hot at 29MHz.  . 

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Reality never ceases to amaze me, as long as I live and no matter how much pain I have to endure (and I know from what I speak) I will always go to sleep in anticipation of what the next day brings like a little girl on Christmas eve. [/i]

  When I was writing the manuscript for the 1988 QST article, I had no idea that I was tipping over a hornet's nest of "recognized experts". 
cheers Susan
Rich, ag6k