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[K7JQ]

IMO, unless you’re a long-winded RTTY ragchewer, I see no need for a brick-on-key full power 100% duty cycle 24/7 amp. Tube vs SS amp?…when was a transceiver last manufactured with a tube PA?

[KB6DYA]

Good morning. I got the Icom pw 2 details from a u-tube by Ray Novac from Icom. 73

[K7JQ]

Good morning. I got the Icom pw 2 details from a u-tube by Ray Novac from Icom. 73

OK…I just watched that YouTube interview with Novak, Icom’s NA sales rep. Nowhere does he say “100% CCS any mode no time limit”. The interviewer pushed him on duty cycle, and he responded with “full power (1KW) FT8 and RTTY *contests*, no problem”.

Although I’m a big promoter of SS amps (based on experience with them), I don’t see any of them going key down at full power rating, no time limit before eventually faulting from maximum safe temperature build-up.

[KA4WJA]

Bob, K7JQ,
I do sort-of agree....but, there are other applications, like desiring a clean / low IMD signal at legal-limit in whatever mode you're using (as well as desiring the tank circuit to do better than just "survive" in high-VSWR [> 4:1], as well as not wanting the power supply to limit the amp...etc. etc..)

IMO, unless you’re a long-winded RTTY ragchewer, I see no need for a brick-on-key full power 100% duty cycle 24/7 amp. Tube vs SS amp?…when was a transceiver last manufactured with a tube PA?

Preface:  I mean NO offense to anyone here!
I am NOT digging against the Mercury or Elecraft at all!
Please nobody infer anything rude here at all!!!!!!!!!!!!!!!

I guess, I need to start my posts with a disclaimer now, huh?
Okay....no onto my further thoughts:

We have folks posting the drive vs. output graphs of amps like the KPA-1500 and Mercury IIIs, showing the 1-db compression point well below their advertised / spec'd output!  (which is where they have already departed from being "linear", but then they are run right up to [or even beyond] their advertised / spec'd outputs, running seriously-non-linear)
Depending on which ham's graphs you use, the 1-db comp point of the Merc IIIs is ~ 750 - 800 watts, I think....but, it's advertised as a "1200 watt" amp....(and, I think the KPA-1500 is around 985 watts?  but, I'd have to look and see, so don't take that as an absolute)

So, if we look at amps that have the device and heat dissipation that can handle "brick-on-the-key" at its advertised/spec'd output, then 99% of the time, this same amp will usually be well below its 1-db compression point at this advertised/spec'd output (and hence, hopefully operating "linearly"!), rather then being 30% to 50% above its 1-db compression point, and being a dirty amp.

So, while "brick-on-the-key" might not be a necessary spec for most hams, it darn should be nice if many amps were not being run beyond their linear range, yes?
And, one way to do that is to use an amp that is actually "linear" at its advertised/spec'd output....or just buy an amp and only use it to ~ 2/3's of its advertised / spec'd output....
{I don't think I need to write which one would be my choice....but, to be clear, I actually do both! Yep, I run my amps below their advertised/spec'd output....but, that's a whole 'nother discussion, 'cuz their advertised outputs are > legal-limit... }


And, then we have the other end of the spectrum, so-to-speak...
As I posted yesterday:

P.S.  For the naysayers out there, who wonder who needs "brick-on-the-key" at 1500 watts (or 2250 watts, as in Canada)....I do agree it's a darn small share of hams....BUT...

But, when you have the opposite end of the amp users out there pushing their amps WAY beyond the limit (over on QRZ just yesterday, we have a guy querying about what went wrong [poof!] in his AL-811 with three 811'a, when he was using on FT-8 at 400 watts!!!!!!), and it seems that none (or damn few) even comprehend what IMD is, nor what the 1-db compression point of their amp is, etc....well, I'd rather have everyone that could afford it run a "brick-on-the-key" amp!

No, BS....this was actually a thread on the zed....
He was running the snot out of an AL-811 (3-tuber) at > 400 watts on FT-8!
It blew up / blew at least one tube....and, he wondered why/how?

So...
So, there are some reasons why a "brick-on-the-key" amp is nice! 
Just not a necessity for most.


Hope you don't mind my slight disagreement with ya' Bob?

73,
John,  KA4WJA

[KA4DPO]

Rob,
You're welcome!

The way I'm now interpreting your question(s) is less about the Alpha 9500, and more like many of the questions here regarding amp selection....

Most people think I'm a decent, nice guy. I've given my life to public service since 1976 when I was originally licensed. I took time off for the military and then a career. I'm not new here but confess that there are things I don't know and so I ask.

TO BE BLUNT...

I don't need to be talked down to. Your condescending assumptions are suggestive of why new hams are afraid to ask questions.

These are the typical:
"what amp should I buy?" ....
"Solid-State or Vacuum-Tube?"

I asked about a high-end Alpha.

I'm sorry you felt the need to dismiss my question as being about selection and "asked and answered." That was just rude. I run a Facebook group with over 100k active users and I've learned to speak up. I would experienced HF user as well as having multiple repeaters on the air and being more than familiar with service monitors and other test equipment. We're going down a road that we didn't need to.

I have an assortment of amplifiers and I want better.  I appreciate quality and performance which is why I have a SteppIR. Great antenna; less power required. I want better. Based on friends that have the Alphas and the clean sound they seem to put out, that's the direction I was headed.

What this thread has brought out is selection. Because this thread took a detour I am now looking at the KPA-1500. It's current and it's solid state. It also has very good reviews. I'm also looking at the Palstar 1500w auto tuner. I've been spoiled running a SteppIR. Although the KPA will tune a 3:1 it's not a factor with a SteppIR. I'm upgrading because I am moving further north from the equator and want the edge. I'm also not going to die and leave my money to my kids.

I don't want to be a complete horse's patoot by not acknowledging the wealth of information that you have provided. To be candid, I know much of it. But there will be someone that comes along with the question that's been asked and answered. My comment here should not be a conversation ender.

Consider the source.  The guy did not even attempt an apology.

[KA4DPO]

IMO, unless you’re a long-winded RTTY ragchewer, I see no need for a brick-on-key full power 100% duty cycle 24/7 amp. Tube vs SS amp?…when was a transceiver last manufactured with a tube PA?

I completely agree, the brick-on-the-key thing is way overblown. 

I also disagree with the notion that solid state amplifiers are somehow "not as linear" as tube amps.  That is pure nonsense.

[K7JQ]

Bob, K7JQ,
I do sort-of agree....but, there are other applications, like desiring a clean / low IMD signal at legal-limit in whatever mode you're using (as well as desiring the tank circuit to do better than just "survive" in high-VSWR [> 4:1], as well as not wanting the power supply to limit the amp...etc. etc..)

IMO, unless you’re a long-winded RTTY ragchewer, I see no need for a brick-on-key full power 100% duty cycle 24/7 amp.

So, there are some reasons why a "brick-on-the-key" amp is nice! 
Just not a necessity for most.


Hope you don't mind my slight disagreement with ya' Bob?

73,
John,  KA4WJA

John,

I never mind disagreements, as long as they don't get personal. As I've admitted on other posts, I'm not the sharpest technically inclined tool in the shed, but in my 63 years as a ham, I've picked up enough along the way to be dangerous . I don't disagree with your informative posts, and admire your knowledge.

But I'm an amateur radio *operator*...not a tinkerer. I get on the air as mostly a CW (to a lesser extent SSB and RTTY, no FT8) contester, like 45 contests a year. I buy quality equipment that meets my needs (not according to the best on the Sherwood list), assemble an efficient station, and operate it according to its specs. On SSB, I'm very cognizant of audio gain, compression, ALC, drive power to an amp, and don't run it past its ratings...never been accused of a dirty signal.

I deal in what's *practical*, not necessarily what's *optimal*. The lowest IMD is nice, and a very important spec for the "purists" (BTW, where's Zenki been?). But for all practical purposes, a *quality* manufactured SS amplifier (even though the IMD and linearity is not as good as a tube  amp) is good enough not to dirty up the amateur bands if operated correctly.

I agree with you that a brick-on-key amp is "nice", but certainly not a necessity nor practicality, probably for 98% of all ham radio operations. Besides, what other manufacturer makes a brick-on-key, 24/7 claim other than Alpha? And where is Alpha today? So far, MIA.

So to wrap it up, I stand by "unless you're a long-winded RTTY ragchewer...."  .

73, Bob K7JQ
 

[VE7RF]

Rob,
1)  Okay, you now let us know a tiny bit more:

I have an assortment of amplifiers and I want better.

While we still don't know what your use/application is, nor what assortment you have, nor what "better" means to you (more reliable, easier to tune, cleaner IMD, more power, 100% duty-cycle at full output, etc. etc. etc.?  we have no clue)
So....with that general "question"....here you go:

a)  In my opinion, the Alpha 77Dx is the finest desktop amateur HF amp ever made....
You can find a clean one, in good shape, for ~ $3000 - $4000, with a good 8877 in it.
The amp will last a lifetime!
The 8877 will last you many decades! 
It (and the 77Sx) is the cleanest (IMD) desktop amateur HF amp made.
Wicked reliable, extremely easy/quick tuning, etc. etc....

b)  In my opinion, the Henry 3KD-Premier 8877 is tied for second-place (along with my personal fav the Alpha 77Sx...but I won't bother to detail that again)
Henry didn't make that many (but you can find some other Henry 3K's that have been modified/upgraded to a 3KD-Premeir 8877, as well)....I haven't seen any for sale in a while, but have a look around, you never know.


c)  In my opinion, the Henry 8K Ultra (big, heavy, 2-piece unit....with desktop control box and remote amp console) is probably the finest amateur HF amp made....but it is not a desktop amp, and it ain't for the squeamish!   
I've seen them sell for ~ $10k - $12k....but, I personally don't think I'd pay more than $6k - $8k
It, and its 3CX3000 tube, will last you for decades!
And, it's damn clean in IMD department as well! 
 

There you go...
In my opinion, those are the top 4 choices, in regards to "wanting better".
(if we had more info about what you interpret as "better", and what your application / use is, well then we could all probably give you more specific answers and most importantly the reasons that we recommend or not recommend a particular amp for you / your application)

If none of those appeal to you, or if none of those fit your application, or if none of those fit your definition of "better", then have another look at the Alpha 9500, and give Mike D. a call or email, at Alpha!
That would be my recommendation.


2)  As for me being rude?
Huh? 
{I'm not certain what Facebook (where I've never been, btw), your career, etc. has to do with answering your question(s) regarding the Alpha 9500, its "value", and/or other amp choices....nor do I grasp what could have possibly caused my polite (but, direct and blunt) comments to be so misunderstood....but, those are really ancillary matters....what matters here is that I tried to help / you get the answers that you desire / and we all part as friends....in my opinion, anything else is just "noise"?}

Seriously, to be blunt....I think you completely misinterpreted my posting!
And, I truly regret that!

I think I'm a pretty decent guy, too...
And, I never for one second tried to "talk down to you"! 
If that is how you perceived my attempt to help, there is nothing I can do now to "un-do" that....but..
But, if you do care to read the many other posts of mine, and/or drop me an email or phone call, I still wish to be of assistance.....(if you choose not to do so, no worries here)

Not to argue anything, but perhaps I should clarify?
You asked about the '9500....I (and others) answered you.
You asked for more but were not specific, so I answered you again with more info and mentioning that all I was able to do was answer in generalities as I didn't have any specifics.
I don't think there is anything wrong with any of that.

You seemed to take offense to my reference of the variety of questions to consider?
But, Rob, this wasn't meant as any personal attack ---- rather as a way to spur on some more specific info from you, so we could all provide you with further assistance.

Again, I think you simply misunderstood the effort that I was making to help.
And, that is regretful. 


Anyway, I do wish you well....and I do hope that whatever amp you choose you are happy with!
73,
John,  KA4WJA

You forgot to mention the Henry 4 k ultra..with it's single 8877. But it only covers 80-10m.
IMO, the 8K ultra is a basket case. There are several versions of it. It's not engineered, it's ill conceived.  Ever worked on one?  It's a dog's breakfast.  If you do buy one, make sure it has the very latest upgrades done to it.  Those were done just before they stopped making it.   There is way too much to go wrong in that amp.

The 77DX has a 3 min warm up..and no auto tune / auto band switching.  Which is just fine for K3LR, who runs a multi -multi contest station.   IE:  all ampS tuned for CW...or tuned for SSB.   W3LPL uses monoband amps, that's even simpler and cheaper..at his MM contest station.   A slew of HB monoband amps is dead simple to optimize for each band.

The SMPS supplies to run a.. 1.5 kw ..'brick on key' SS amp is a non issue.   They come in 3 kw CCS or 3.3 kw CCS versions.   You can also parallel 2 or more of em..with a 50-50 current split.   They are relatively inexpensive.   Cooling the LDMOS devices is a different issue.  The devices will handle the power...provided they are effectively cooled.  Water cooling is  probably the only real effective way of extracting the heat..then dumping that heat to the room, via an air cooled external radiator.

I noticed on my  FT-1000D's, they used interlaced heatsinks. (fins facing each other, and meshed, but not touching, one device per heatsink). Harris did the same on their Channel 2  TV Pa's...which are now on the surplus market, and being converted for 6M use.  You want  lots and lots of narrow thin  fins on any heatsink, not thick fins, with wide spacing between fins. Harris got it right.   Also beware  of the dead air spot on either side of the motor hub on any fan.

Look at the fins inside any Eimac bigger tube, loads of em, and no thicker than a razor blade..and made from silver plated copper.  (those thick 'fins' at the top and bottom  of a 3x3/6/10/15/20 are  actually..'struts', used to hold the outer cylinder assy to the tube).     

Aluminum only conducts heat 57% as good as copper, that's why copper spreaders are used on current production SS amps.

As far as B+ supplies for tube amps goes, a bigger xfmr is only a click away.   That or a 2nd identical oem xfmr can be paralleled.    The RF deck is a different story.  For brick on key, 100% duty cycle, everything in the RF deck must be sized correctly.  Tank coils will dissipate 4 X as many watts with a CXR..vs  SSB.  Ditto with the poor bandswitch..and anything else with RF current flowing through it... including tuned inputs, bandswitch / relays for the tuned inputs, etc.  Airflow must be increased by a bunch.  All doable....just requires the correct sizing of components,  and/or cooling of existing components. 

[VE7RF]

I find it interesting that Alpha used Pin diode TR switching on the 87A... but used a vac relay on the 9500.

[AF6D]

Consider the source.  The guy did not even attempt an apology.

Unbelievable. You're actually expecting an apology from me because I spoke up against a condescending individual?

My name is BOB, not Rob.

I asked a very simple and straightforward question. I asked about the Alpha 9500. From the outset I asked that given the current state of the 9500 and lack of activity on their website, and other factors, if I was better off considering solid state. From the outset my question was about selection. I didn't need it to be tossed back at me in a condescending and arrogant manner. Considering I was asking about a specific Alpha 9500 to be compared against other alternatives, the focus of my question was narrow and therefore probably not "asked and answered" previously. But now you want me to apologize for asking a question?

These are the typical: 
"what amp should I buy?" ....
"Solid-State or Vacuum-Tube?" ....
"how good IMD do I need?" ....
"do I need 1500 watts out?" ....
"do I need 100% duty-cycle, no time-limit, 'brick-on-the-key'?" ....
"if I desire a 'tube amp', which tubes should I avoid / which ones to look for?" ....
"if I desire a SS Amp, which devices should I avoid / which ones to look for?" .... 
"are there 'no-time-limit' SS Amps?" ....
"what is the 'best' amp?" ....
etc etc.
etc....

I didn't ask any of these questions.

I am not a new ham and I am certainly not new to operating. It should have been assumed that I am an HF and 6 m operator and it required no further explanation from me. I'll be the first to tell you that I am not an Electronics Engineer. I learn and I grow. I ask questions deliberately so that those that are more knowledgeable can hopefully distill the answer to the question down to a simple paragraph or two. I try to ask questions that others that may come along in the future looking for a similar answer may find it.

Now this thread stands as a strong suggestion as to why new hams don't come and ask questions. If this is how you'll treat an experienced ham why should they? Belittling someone for asking questions is simply arrogance. You don't need to know anymore about me. You don't need to know what other amps I have. That's just your elitism showing thinking that you have some right to interrogate me and ask questions to your satisfaction before answering. I joined this group in September, 2008.

To those of you that joined the conversation and sincerely offered your input, as well as some of you that had a similar question but not yet asked, I offer you my most sincere thank you.

BOB Ricci
AF6D
Lake Arrowhead, CA

[N2WQ]

Bob,

If you haven’t already, take a look at OM Power 2501A. Current, modern, fully supported amplifier from a company that is actually in business. Uses a single FU-728 that is readily available for under $400. Built-in remote access server if you are interested in operating your station remotely. The latest firmware adds true auto tune (vs memorized settings).

Rudy N2WQ

[K7JQ]

Bob,

If you haven’t already, take a look at OM Power 2501A. Current, modern, fully supported amplifier from a company that is actually in business. Uses a single FU-728 that is readily available for under $400. Built-in remote access server if you are interested in operating your station remotely. The latest firmware adds true auto tune (vs memorized settings).

Rudy N2WQ

That would be another good choice, as well as an Acom 2000A, if you’re still considering a legal limit, auto-tune tube amp. Alpha is still wallowing in the mud…who knows when/if they’ll be up, running, and delivering amps.

The only negative I’ve heard/read about OM Power amps is their loud blowers. Maybe they’ve done something to remedy that with the xx01 series.

[K7JQ]

Bob,

If you haven’t already, take a look at OM Power 2501A. Current, modern, fully supported amplifier from a company that is actually in business. Uses a single FU-728 that is readily available for under $400. Built-in remote access server if you are interested in operating your station remotely. The latest firmware adds true auto tune (vs memorized settings).

Rudy N2WQ

That would be another good choice, as well as an Acom 2000A, if you’re still considering a legal limit, auto-tune tube amp. Alpha is still wallowing in the mud…who knows when/if they’ll be up, running, and delivering amps.

The only negative I’ve heard/read about OM Power amps is their loud blowers. Maybe they’ve done something to remedy that with the xx01 series.

...and the Acom 2000A actually states "Constant carrier modes 1500W output - NO TIME LIMIT with auxiliary cooling fan". Sounds like a brick-on-key feature to me.

[N2SR]

...and the Acom 2000A actually states "Constant carrier modes 1500W output - NO TIME LIMIT with auxiliary cooling fan". Sounds like a brick-on-key feature to me.

I added the PS fan myself.  Not for RTTY, but just to keep everything cooler.  I have noticed a slight drop in tube exhaust temperatures. 

[K7JQ]

...and the Acom 2000A actually states "Constant carrier modes 1500W output - NO TIME LIMIT with auxiliary cooling fan". Sounds like a brick-on-key feature to me.

I added the PS fan myself.  Not for RTTY, but just to keep everything cooler.  I have noticed a slight drop in tube exhaust temperatures.

I'm a big fan (pun intended) of adding more cooling capability to any amplifier, if it doesn't add too much more noise in the shack. I purchased a variable speed, two muffin fan device from Amazon, and placed it on the cabinet top vents of my Acom 1200s to assist the exhaust flow of heat over the PA module. It seems to lessen the normal increase on the temperature indicator over just the internal fans.