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[K6BRN]

This issue is really just a matter of specsmanship.  Doesn't affect the quality of the product at all.

Sounds like if we simply consider the amp as a 600 Watt FT8/1200 Watt SSB amp, its pretty robust and nobody's going to be disappointed.  But at the very limit, it can do 800W/1500W for a short time, in a pinch, with some risk and added distortion. (i.e. "Crush Depth")

Just forget about ragging rights and all of a sudden the amp looks pretty good. 

600/1200 is nothing to sneeze at.  Beyond (even BEFORE) that point you'll need to be VERY careful that your antenna and feed system are up to snuff - because many amateur antennas and feedline components/installs simply cant handle it.

If you want the ability to do more, spend the money and go with an Elecraft KPA-1500 or maybe a PowerGenius XL (that last name makes me cringe - why dont they just call it the "Flex-Aide Super-Dooper Mighty Amp").  They can run the legal limit with headroom.  Just don't blame the amp when YOU barbeque your antenna and baluns.

Just my 2 cents.

Brian - K6BRN

[N4ATS]

KA4WJA

Why not just enjoy the new horizons? Ya you can critique something day in and day out .. Bottom line, nice sweet amp . very well put together and sounds great.  If you really need something that is "par for you only" cough up a few hundred K and go design it.

Otherwise , every one I talk to loves the sound of it , That's good enough for me...

Life is short , enjoy everything like there is NO tomorrow and ham radio is fun....

[KA4WJA]

Bill, N4ATS,
1)  I think you may have misunderstood my answer to Mike, K6AER?

I wasn't aware that I was being critical...and, I certainly wasn't attempting to "critique" the Mercury Lux (nor the IIIs) at all!

I thought I was clear right up front that I think they're great!
(they're just not my cup-of-tea)

Seriously, as I wrote right up front (and in bold-type and underlined):
 

And, to be clear, I love Kenny!
I think he is doing great!
I wish him much continued success!
He designed these amps (Merc IIIs and Lux) and builds them here in Florida!  (I have no idea who wrote the software/firmware).
But I do know who/where designs and builds the hardware, and's that Kenny and his crew in Miami!

But, neither the Mercury IIIs nor the Lux have much (if any) headroom, neither are clean enough for me, nor are either "brick-on-the-key" amps....so, going from an Alpha to a Lux, would be a hard voyage!

2)  Further, I was answering Mike, K6AER's question regarding what its max output is.....and, attempting to show him (and others?), why there isn't the headroom he was asking about.
But, that doesn't mean there is anything wrong with the Lux.
 
I am not anti-Lux, not anti-solid-state, at all.

And, btw....if I was looking for SS PA, I don't have to "go out and design it myself".....there are folks in JA that have them for sale right now....in addition to the commercial SS PA's from JRC (which are wicked-nice, BTW...and wicked pricey, too), there are some rather sizable amateur SS PA's from Japan as well...This is the only one I remember the website of, http://www.bear-el.com/

So, they are there, they are available, they are nice.....and they are pricey, too. 
(the Mercury just isn't one of them)

KA4WJA

Why not just enjoy the new horizons? Ya you can critique something day in and day out .. Bottom line, nice sweet amp . very well put together and sounds great.  If you really need something that is "par for you only" cough up a few hundred K and go design it.

Otherwise , every one I talk to loves the sound of it , That's good enough for me...

Life is short , enjoy everything like there is NO tomorrow and ham radio is fun....

3)  Bill, I agree with you 100%, that ham radio is FUN!
And, I do the best I can, everyday, to enjoy everything like there is no tomorrow! 

"New horizons"?  Sure....but this does depend on your definition of them, yes?
And, heck, I'm still using my ~ 44 year old Drake TR-7, daily!  (and, my Alpha 77)
So, do ya' really think I'm the target customer for a Mercury Lux? 



4)  Now, Bill....I'm hesitant to drift this thread of Mike's....but...
You know that someone saying they like the way you sound on-the-air, has anything at all to do with the amp you're using.  (unless you had some sort of Class C, weird CB-amp-type biasing, amp....it is darn near impossible for any HF ham amp, let alone a commercially made amateur HF amp, to "distort" your signal on-channel enough for someone to "hear" your amp)
Nobody needs to remind you of that. 

Hmmm, maybe they mean that they like the sound of the cooling fans?  Hi hi (sorry, could resist)

Seriously, Bill....you understand RF, you understand IMD, etc., I wouldn't have thought you'd whip-out the ole' "everyone says it sounds great" line.....
I mean, when discussing a mic, or a particular transceiver....sure....but an external amp effecting your on-channel audio?  (it would need to be a wicked-bad amp to have noticeable distortions on-channel)



Anyway...as I wrote up top, I think you just misunderstood what I wrote....not panning the Lux at all, just answering Mike's question(s).

73,
John,  KA4WJA

[KA4WJA]

Mike, K6AER, et al,

Just a nice tidbit of Brian's to highlight here:

If you want the ability to do more, spend the money and go with an Elecraft KPA-1500 or maybe a PowerGenius XL (that last name makes me cringe - why dont they just call it the "Flex-Aide Super-Dooper Mighty Amp").  They can run the legal limit with headroom.

Mike, as Brian points out, the bigger "legal-limit" SS PA's do have slight "headroom" of approx 0.8 to 1.2db.  That might be acceptable to you?
(it's not the 2db+ you mention that your present amp has....but, might be enough?)


According to their manuals:

The Elecraft KPA-1500 will fault-out at 2005 watts out (as well as at a certain max device current, that assumes ~ 55% - 58% eff).

The Flex Power Genius XL will fault-out at 1650 watts out on 160m,  and 1750 watts on 20m,  and at 2000w out on the other bands (and, also has device current fault-out, which also limits max output).

The Expert 2K-FA doesn't seem to have a max power out fault, but does have max device current, max input drive power, max heat, etc. fault-outs, and seems to be have a max out of ~ 1800 - 2000 watts.

{of course, all these "legal-limit" SS amps also have heat/temp, time, and mode/duty-cycle power limits....that should effectively restrict max power to ~ 1500 watts out PEP SSB, except for occasional higher SSB Voice peaks....as well as IMD/linearity power-out limits that are, of course, lower, depending on what you consider "linear-enough"}


So, Mike, it looks like if you want more headroom than these, you're gonna' need to pony-up the BIG $$$$, or stay with tubes.


I hope this, together with my earlier post (  https://www.eham.net/community/smf/index.php/topic,137764.msg1280066.html#msg1280066 ), on the preceding page, helps?


73,
John,  KA4WJA

[N4OGW]

Sorry, the QRZ thread I linked can't be read unless you log in there. The problem isn't heat or power supply headroom.

LU6PSG's point there is that for these solid state amps, the highest linear output is set by the LDMOS voltage and the impedance ratio of the matching network. If you use two devices but still the same 1:9 matching network that you use for a single device, you end up with a maximum linear power point that is pretty much the same as for using one device.

Combining two pallets or using a different matching ratio (1:16) is better for a legal limit amp.

Tor N4OGW

[KA4WJA]

Tor,
I'm with you (and LU6PSG, and Jim, and, et al).
More importantly, I agree with you all. 
(heck, some of my posts on IMD even rival good ole "Zenki's".... hi hi)

But...I think Mike, K6AER, was simply asking about the max saturated out, or max output capable for CW, etc. where linearity isn't an issue.
Which the answer here for the Lux, is ~ 1500 watts. 


(Of course, in my opinion, that's ~ 4 - 5 db above the max "linear" output....but, I don't think that was what Mike was asking)


73,
John,  KA4WJA

[K0UA]

I have no idea what the maximum output power of the LUX is, but I did note on the facebook page I saw one fellow claimed his would do 2000 watts "easily". I know my Mercury IIIs will do right at 1300 on some bands. I don't drive it to that level ever, but I have run it at 1150 on SSB at times. But usually shoot for 1000. So don't take the 2000 claim as gospel but it might do that. It makes sense that it "could". I suspect it would not be very linear.

[N4ATS]

I have no idea what the maximum output power of the LUX is, but I did note on the facebook page I saw one fellow claimed his would do 2000 watts "easily". I know my Mercury IIIs will do right at 1300 on some bands. I don't drive it to that level ever, but I have run it at 1150 on SSB at times. But usually shoot for 1000. So don't take the 2000 claim as gospel but it might do that. It makes sense that it "could". I suspect it would not be very linear.

My LUX cruises along at 1400 to 1500 watts EASY. I read it on a Alpha 4510 meter. It is also super quiet and if you need a tad more cooling , you just touch the fan max button but you still cant hear it.

[VE7RF]

I think the idea here is to optimize the operation of any SS amp.   Optimize it, not blow stuff up, or run it on the ragged edge.  You want a bit of wiggle room....esp if ant swr is not flat, and no tuner used, etc.   If that requires reducing drive power a bit, so be it.  The difference between 1200 w pep and 1400w pep is a meager .67 db.  Nobody is gonna hear the difference.  However, the difference in heat, IMD, overall reliability, headroom, etc, may well make the case for slightly reduced power on a lot of SS amps. 

Average PO on SSB is typ only 29% of pep.   With 1400-1500 w pep out, average PO is only 406 - 435 watts....and that's with a lot of processing used.  On  CW, average PO is a lot more than SSB.   On data modes,  average and pep are the same.

If you operate, or intend to operate data modes, be aware of the limitations of the SS amp in question.   Reducing PO from 800 watts down to 700 watts, is only .58 db.    Then factor in operating practice.  Tuesday night ragchew  / roundtable on SSB, with 6 other stations, or  hardcore 48 hr hour RTTY contest mode.  What's the ambient temp in the shack, 70 deg F.....or 85 deg F...and no AC.

All these SS amps are probably fine, just find the optimum PO to run them at.

[VE7RF]

I know quite a few people combining amps but be careful of phasing, if one or the other is off, your amp(s) will hopefully shut down before destroying one or the other. The only true way to phase them correctly is with a scope and tweaking the coax to combiner lengths. We played with this at a shack of friend of mine and he went thru a costly learning process...

Sage advice.  The combiners from OM-power and also ACOM  are not cheap. In the manuals for em, if one amp dies for whatever reason, or one amps PO is a lot less than the remaining amp(S), the internal dummy load in the combiner has to handle the difference .  In one of the manuals, if manually tuning up a tube amp, one amp at a time, it has to be done very quickly.  You only have XXX  seconds to complete the tuning, or the DL + combiner will overheat, and key line is opened up.   The ACOM combiner will  handle 3 x amplifiers, and is rated for 5 kw.  The OM power combiner will handle just 2 x amps..and is rated for 10 kw..and uses a 7-16 DIN for the output of the combiner.

Considering the HUGE expense of the combiners, and the cost of a 2nd, identical amplifier, total cost is absurd....for a lousy 3db.   And if one amp dies, the 2nd amp has to be disconnected entirely from the  combiner.

[K7JQ]

My LUX cruises along at 1400 to 1500 watts EASY. I read it on a Alpha 4510 meter. It is also super quiet and if you need a tad more cooling , you just touch the fan max button but you still cant hear it.

^^^^^^^ From a technically savvy ham that actually *owns* and operates one. All other posts here that hedge on its capabilities are just opinions.

[K7JQ]

If you operate, or intend to operate data modes, be aware of the limitations of the SS amp in question.   Reducing PO from 800 watts down to 700 watts, is only .58 db.    Then factor in operating practice.  Tuesday night ragchew  / roundtable on SSB, with 6 other stations, or  hardcore 48 hr hour RTTY contest mode.  What's the ambient temp in the shack, 70 deg F.....or 85 deg F...and no AC.

All these SS amps are probably fine, just find the optimum PO to run them at.

Exactly. I think the fact that Kenny builds in a digital (continuous carrier) 800W fault safeguard is a good thing. That will prevent an op from recklessly trying to operate the amp balls to the wall on that mode, and risk blowing it up. It will keep the amp in the shack, and not at the repair center . Despite what a manufacturer’s “continuous carrier” specs quote, I think most SS amps (and many tube amps) should be operated at a much reduced power in digital modes.