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[K0UA]

Not designed in Russia.  It was designed and manufactured in Florida.  The Russian wrote the firmware. That is why the display looks nearly the same. The boards don't look alike at all.

So, just to be clear, the Mercury IIIS shown in all the RZ1ZR videos in the link above were designed, assembled, and distributed in the U.S. then sent to RZ1ZR in Russia?

And RZ1ZR had no part whatsoever in the hardware design? 

Paul, W9AC

Kenny says he designed it, and all of the parts and boards are assembled in Florida. Whether he had any input on the hardware design, I don't know. But I understood RZ1ZR wrote the firmware.

[K7JQ]

How many typ ham ants are ruler flat across all 10 bands... none of em.  So a tuner will be required. The RF-kit comes with the tuner, so it's not optional...(like it used to be).  Any tube amp will handle a 2:1 swr.    SS amps won't.

IMO, if I'm spending that kind of money, I may as well spend a tiny bit more..and get the real deal.

Antennas don't have to be "ruler flat" for the newer LDMOS amps to operate. They *will* handle up to a 2:1 SWR, or higher if you reduce power a bit (depending on the amp), before they're programmed to fault.

Just like transceivers with built-in tuners, the RF-KIT tuner will only handle up to a 3:1 SWR. Many off-resonant and low-band antennas might still require a more wide ranging external tuner anyway.

Log-periodic and 10, 12, 15, 17, 20 meter multi-band yagis will present less than 2:1 SWR edge to edge, as will individual dipoles. Self-adjusting motorized (SteppIR) antennas from 6-40 meters will present less than 1.5:1 SWR across all their covered frequencies. Personally, living in an HOA community, I use my Acom 1200s into a ground-mounted motorized screwdriver antenna...covers 10-80 meters with less than 1.7:1 SWR across all frequencies. No interest, nor room, for 160 meters.

And finally, maybe one already has a high-power manual or automatic tuner, rendering the built-in one redundant/superfluous. If the built-in tuner craps out, you have to send in the entire amp for service. Plus, you can use an external tuner with other radios

Please understand, this is not intended to argue with you. Having experience with three SS amps  over a twelve year period, just presenting some examples of not "requiring" a tuner with SS amps. If one's antennas fit into some of the scenarios above, then the LUX is a bargain at $1,190 less than the RF-KIT (and you're not into QSK, and 800W digital is good enough).

Bob K7JQ

[K0UA]

If you can't work it with 800 watts digital, you probably are not going to work it with 1500

[K6AER]

I would like to thank everyone who posted a reply to my question but no one or suggested web site, manual or review, answered the question of what is the maximum output of the Mercury LUX amplifier.

the ability of an amplifier to produce increased output with low IMD is a function of reserve amplification and power supply capabilities.

My current 1500 watt (tube) amplifier will put out 2.4 KW CW. As a result my measured IMD on 20 and 40 meters is better than -42 dB  on the 3rd-7th order. Before I switch to a solid state amplifier I want to make sure it will operate at legal limit, cleanly. I'm reluctant to drop $5K+ on an amplifier when the simplest of specifications are ignored.

73's, Mike K6AER, NM

[K7JQ]

I would like to thank everyone who posted a reply to my question but no one or suggested web site, manual or review, answered the question of what is the maximum output of the Mercury LUX amplifier.

the ability of an amplifier to produce increased output with low IMD is a function of reserve amplification and power supply capabilities.

My current 1500 watt (tube) amplifier will put out 2.4 KW CW. As a result my measured IMD on 20 and 40 meters is better than -42 dB  on the 3rd-7th order. Before I switch to a solid state amplifier I want to make sure it will operate at legal limit, cleanly. I'm reluctant to drop $5K+ on an amplifier when the simplest of specifications are ignored.

73's, Mike K6AER, NM

Mike,

I think your next step is to try to get the info from the horse’s mouth…call or email Kenny at KM3KM Electronics.

The LUX has two BLF-188 devices on its PA pallet, “capable” of 2,800W…technically plenty of headroom. But the digital limit of 800W leads me to believe that there are probably power supply, cooling, or filter limitations that would inhibit achieving much excess capability.

From what I’ve seen, *if* a SS amp manufacturer even publishes IMD stats, they’re generally around -30 to -36 dB max at rated power output. The RF-KIT just says “highest spectral purity”… no numbers. They’re not gonna match up to what tube amps can achieve.

I know the three SS amps I’ve used over 12 years have performed without a hiccup through many long contests. I never tried pushing them beyond their ratings, and never had any reports of distortion or dirty emissions. Good luck!

Bob K7JQ

[N4OGW]

I suggest reading the comments by LU6PSG:

https://forums.qrz.com/index.php?threads/km3km-mercury-iiis-amp.780467/page-17#post-6269476


Tor N4OGW

[WA2EIO]

I would like to thank everyone who posted a reply to my question but no one or suggested web site, manual or review, answered the question of what is the maximum output of the Mercury LUX amplifier.

the ability of an amplifier to produce increased output with low IMD is a function of reserve amplification and power supply capabilities.

My current 1500 watt (tube) amplifier will put out 2.4 KW CW. As a result my measured IMD on 20 and 40 meters is better than -42 dB  on the 3rd-7th order. Before I switch to a solid state amplifier I want to make sure it will operate at legal limit, cleanly. I'm reluctant to drop $5K+ on an amplifier when the simplest of specifications are ignored.

73's, Mike K6AER, NM

You asked for info on IMD/headroom etc.  for the Lux, but you say here that YOU measured your tube amp's IMD yourself to come up with the info.   If it is a commercially made (not homebrew) unit, are the figures that you came up with available from any manual, review or on-line source, such as you requested?   

[VE7RF]

I suggest reading the comments by LU6PSG:

https://forums.qrz.com/index.php?threads/km3km-mercury-iiis-amp.780467/page-17#post-6269476


Tor N4OGW

LU6PSG nailed it.  The 188 (and 189) devices are split into 2 x halves...(and each half consists of paralleled multiple mosfets...and if just one tiny mosfet fails shorted, the entire device is toast).  On the merc-3, only one 189 device is used and  only one splitter/ combiner is required.   On the LUX (and B26 german amp), they paralleled the 2 x halves of each device into one big MOSFET.   One device is push, the other pull.  Done that way so only one combiner is required.  The alternative would have been to use a combiner  for each device, and each device operating in PP.  Then a high powered combiner, to combine the outputs of the pair of smaller combiners.   To pull this off, a splitter would be required, then 2 x more splitters. 

Installing 2 x devices onto the same heatsink, with 1" between them, defeats the overall heatsink capability. (the devices  cook each other).  To really do it right, each device should be on it's own, separate heatsink.   Yaesu did that on it's FT-1000D, and used interlaced heatsink fins.  Harris also did the same on it's SS  ch-2 TV TX pa's..that are now available surplus ( and being modified for 6M use).   Same deal, interlaced heatsink fins. That mess is formed into a  4 x sided tunnel ram, with air being blown from one end.

Not quoting complete IMD specs from IMD3  to IMD21 (at rated max power)  is reprehensible at best. What are they trying to hide ?   Bragging about harmonic suppression instead... is a moot point at best. 

[VR2AX]

no one or suggested web site, manual or review, answered the question of what is the maximum output of the Mercury LUX amplifier.

I respectfully think this speaks for itself... nobody knows, or if someone does, they don't think it would be wise to publish the data.

IMO $5k might be better spent on two MIIIs plus (as a longer term investment) a combiner. OM, Acom and SPE make combiners, all around the $2k mark plus or minus. Acom's does three amps the other two although the SPE is clamed to work on 6m. Now, even the modern ham knows or should know their 2x and 3x arithmetic tables.

[N4ATS]

Received my LUX last week (12/1/2022) and have been running it at near legal limit for over a week driving it with a TS-890 Kenwood and a Heil GM-5, some 45 contacts and several hours of rag chewing on 17 and 20 meters. All I can say is wow, what a nice amp at a great price. Operation is smooth and seamless with the proper COM cable. The BEST part is, with out eagle sharp vision that I used to have, I can actually see the nice large color touchscreen with out having to switch glasses or get the magnifier out. Repairing amps and radios for over 45 years and seeing blown amps in ALL brands does not make me skeptical of trying a new amp like the Mercury...I sold my Alpha 8410 and this LUX  took its place. It will be in my shack for quite a while...I am almost always on 18.133 after 7 at night , feel free to give me a shout to hear it  "N4ATS"  www.N4ATS.com

[N4OGW]

I suggest reading the comments by LU6PSG:

https://forums.qrz.com/index.php?threads/km3km-mercury-iiis-amp.780467/page-17#post-6269476


Tor N4OGW

LU6PSG nailed it.  The 188 (and 189) devices are split into 2 x halves...(and each half consists of paralleled multiple mosfets...and if just one tiny mosfet fails shorted, the entire device is toast).  On the merc-3, only one 189 device is used and  only one splitter/ combiner is required.   On the LUX (and B26 german amp), they paralleled the 2 x halves of each device into one big MOSFET.   One device is push, the other pull.  Done that way so only one combiner is required.  The alternative would have been to use a combiner  for each device, and each device operating in PP.  Then a high powered combiner, to combine the outputs of the pair of smaller combiners.   To pull this off, a splitter would be required, then 2 x more splitters. 

Installing 2 x devices onto the same heatsink, with 1" between them, defeats the overall heatsink capability. (the devices  cook each other).  To really do it right, each device should be on it's own, separate heatsink.   Yaesu did that on it's FT-1000D, and used interlaced heatsink fins.  Harris also did the same on it's SS  ch-2 TV TX pa's..that are now available surplus ( and being modified for 6M use).   Same deal, interlaced heatsink fins. That mess is formed into a  4 x sided tunnel ram, with air being blown from one end.

Not quoting complete IMD specs from IMD3  to IMD21 (at rated max power)  is reprehensible at best. What are they trying to hide ?   Bragging about harmonic suppression instead... is a moot point at best.

Yes, see w6pql.com for examples of combining two amp pallets with a separate combiner. Also www.vk-amps.com

Tor N4OGW

[N4ATS]

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...

[K7JQ]

Received my LUX last week (12/1/2022) and have been running it at near legal limit for over a week driving it with a TS-890 Kenwood and a Heil GM-5, some 45 contacts and several hours of rag chewing on 17 and 20 meters. All I can say is wow, what a nice amp at a great price. Operation is smooth and seamless with the proper COM cable. The BEST part is, with out eagle sharp vision that I used to have, I can actually see the nice large color touchscreen with out having to switch glasses or get the magnifier out. Repairing amps and radios for over 45 years and seeing blown amps in ALL brands does not make me skeptical of trying a new amp like the Mercury...I sold my Alpha 8410 and this LUX  took its place. It will be in my shack for quite a while...I am almost always on 18.133 after 7 at night , feel free to give me a shout to hear it  "N4ATS"  www.N4ATS.com

IMO, what N4ATS wrote above says it all. The LUX is a nice, quality built legal limit SS amp at a great price, warranty, and customer service. Sometimes getting too technical...paralysis by analysis...and you wind up never buying anything . I got on the LUX waiting list in October, and hope to see something before 2024 . I don't need a tuner, and it meets all my other requirements. In the meantime, I'm very happy with my Acom 1200s, but still desire a legal limit amp.

[N4OGW]

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...

Yes, combining two completed amplifiers is not always easy. But building an amp with two combined pallets internally is not hard.

Tor N4OGW

[KA4WJA]

Mike, K6AER,
I need to be brief here....but I think I have the answers you seek.  (hopefully)

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!


1)  BTW, Mike....I think you (and many others looking at modern HF LDMOS amateur amps) may be under the impression that the Lux (or the RF-Kit 2K, etc.) has two modules?  They do not.
They have one module, with two devices on it...
(and that is not the same as having a tube amp with two 8877's or two 4cx1500b's, or two 3-500z's versus amps with only one of these)....

So, while the marketing side can say the amp has twice the amount of device dissipation as an amp with only one of these devices, they have to do something with the HEAT that comes out of these devices in such a small space!   And, do something with the combiner heat, filter heat, etc.   
As well as have a power supply that could handle the device DC power needed in order to fully utilize two devices.  As well as have some sort of linearity at some specified output.


2)  Mike, the short answer you seek, is: 
The Max Output of the Mercury Lux is ~ 1500 watts, assuming good VSWR and not going past the max time in transmit spec....not any "headroom" at all!


3)  The long answer(s) in three parts....

a)  the absolute Max RF Output of the Lux (like most amateur amps) is its Power-Supply-Limited output....according to the manual, the Lux Power Supply "faults-out" at 45 amps....so, 45 amps at approx 53.6vdc = 2412 watts DC input, times 60% efficiency = 1447 watts RF out...and, while I see > 65% to 68% plate eff in Class AB with 8877's, I'm not sure any modern LDMOS HF amp is that efficient....but, even if you think the Lux and/or RF-Kit-2K is that eff, 65% would only yield ~ 1569 watts RF out.

So, it looks like the Lux is "power-supply-limited" to ~ 1500 watts out.


b)  "Heat-Dissipation-Limited" output...and, this (here again, like in most amateur amps), is mode/duty-cycle dependent....and, as I have mentioned a while back (and Jim highlights here), there is a LOT of heat in a very small space that needs to be dissipated....

LU6PSG nailed it.  The 188 (and 189) devices are split into 2 x halves...(and each half consists of paralleled multiple mosfets...and if just one tiny mosfet fails shorted, the entire device is toast).  On the merc-3, only one 189 device is used and  only one splitter/ combiner is required.   On the LUX (and B26 german amp), they paralleled the 2 x halves of each device into one big MOSFET.   One device is push, the other pull.  Done that way so only one combiner is required.  The alternative would have been to use a combiner  for each device, and each device operating in PP.  Then a high powered combiner, to combine the outputs of the pair of smaller combiners.   To pull this off, a splitter would be required, then 2 x more splitters. 

Installing 2 x devices onto the same heatsink, with 1" between them, defeats the overall heatsink capability. (the devices  cook each other).  To really do it right, each device should be on it's own, separate heatsink.   Yaesu did that on it's FT-1000D, and used interlaced heatsink fins.  Harris also did the same on it's SS  ch-2 TV TX pa's..that are now available surplus ( and being modified for 6M use).   Same deal, interlaced heatsink fins. That mess is formed into a  4 x sided tunnel ram, with air being blown from one end.

Not quoting complete IMD specs from IMD3  to IMD21 (at rated max power)  is reprehensible at best. What are they trying to hide ?   Bragging about harmonic suppression instead... is a moot point at best.

So, it looks like  (according to the manual) the "Heat-Dissipation-Limited" output is ~ 1500 watts SSB, and "maybe" 1500 CW, and 800 watts FT-8 / RTTY.


c)  "Linearity-Limited" output, of course is moot on CW....but on SSB, this number is a moving target that depends on what you consider "linear enough"....And, while having a second device on the board (versus the Mercury IIIs) might lead some to think the linearity of the Lux is substantially better, but I have yet to see that.

But, even if the Lux is better, I suspect that finding the output that doesn't negatively contribute to your station's IMD above that of your exciter / transceiver IMD output, will be disappointing! 

Of course, this depends on what exciter/transceiver you're using, but since just about every modern "transceiver" is worse than most of the tube amps, with some / many (?) of our modern rigs being better than most modern SS amps (LDMOS, or not)....

My guess is, most will find the "linearity-Limited" output of the Lux to be < 1000 watts, probably closer to ~ 800 watts or so....again, this depends on your definition of what is "linear enough" and what exciter/transceiver you're driving it with...
(Goodness help us when someone cranks up a '101D/MP up to the top of the ALC scale, and then drives these poor LDMOS amps to 1500 watts out...Ugh!)


Mike, hope that answers your question?  (~ 1500 watts)

73,
John,  KA4WJA