Any prospect of a mid-size linear amp from Flex?

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The new Powergenius linear from Flex is certainly impressive, but it is more linear than I really need.  Is there any prospect in the next few years for a mid-sized linear from Flex; say, one that does maybe 750 watts?  Elecraft makes the KPA500 which looks pretty good, (I would prefer 750 watts over 500 though) but I would rather have one from Flex as an avid 6400M user.  I could spring for 7 bills for a full bore 1500 watt linear, but really I never run that much power and do not especially want to pay for something I don't need.  A 750 watt linear in the $3-$4K range (with a duty cycle that can accommodate PSK31 and FT8) from Flex would be really attractive to me and just the ticket.  Any prospect of this?

de Roger W6VZV
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Roger J. Buffington

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Posted 9 months ago

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Flex has written numerous times that it is not their policy to discuss projections for future equipment, future software changes, etc.  You might want to pose your question directly to the 403A company ( since they build the Power Genius amplifier.
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Roger I hate to tell you how to operate your station but ............ I am going to say this about your post   A 750 watt linear in the $3-$4K range (with a duty cycle that can accommodate PSK31 and FT8) from Flex would be really attractive to me and just the ticket.  Any prospect of this?

Please do everyone on the bands who run these digital modes especially PSK31, don't run any more than 50w. I have seen people using a linear screw up the entire spectrum in PSK31 and FT8 doing this.
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Ken - NM9P, Elmer

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If they are ruining the whole band for everyone, it isn’t because of high power. It is because their rig and/or amp is not properly adjusted and their dirty signal is splattering.

While I don’t own an amp, I have found that there are times where one would have been helpful when the bands are declining. But simply blaming high power for problems on the bands is simply scapegoating for poor operating practices on both operators - transmitting and receiving.
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They go hand in fist Ken I have found what I posted true a huge signal into the PSK area of the band will indeed affect several KC's no matter how clean of signal.
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Roger J. Buffington

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Doug, I hate to tell you, but I hear this all the time, and it is dead wrong.  One of the things that killed PSK31 is a lot of people running around saying and thinking that you could not run more than near-QRP levels.  So when band conditions descended to their present abysmal levels, all these ops running say 20 watts found that their contacts were mostly marginal, and not much fun.  You don't see all the CW Ops running QRP; they know better, despite that CW has a better S/N than most digital modes.  Digital modes are subject to the laws of physics (3db per doubling) just like any other modes. It is perfectly possible to run a QRO signal without distortion -- I never ran PSK31 with IMD worse than -34, the best my PSK Meter could measure. 
Many digital ops, especially PSK31 ops, are ignorant about how to utilize filters when running digital modes.  So if a strong signal is adjacent to them, their AGC lowers their receiver sensitivity and they can't hear other signals.  They then blame the loud signals for their inability to receive.  Good narrow filters will remedy this nicely, but in my experience the vast majority of digital ops are ignorant of this.  (Part of the fault for this was the original MixW instructions, which said to simply put your receiver freq. at say, 14070 and keep the spectrum wide open and click the AF freq as offset.  It works, but badly.)   I have a local who ran PSK31 at around 150 watts.  I have worked weak DX within 300-400hz of him (he is 20+ over 9) using my rig's narrow filters.
Incidentally, it is very clear to me that many FT8 stations are running QRO, you can see this on the Flex panoramic display, where the FT8 signals have greater amplitude than comparable CW signals a bit down the band.  Fine by me.
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What I have seen is that it all depends.  If your on 20m daytime and working states side yeah 25 watts is going to be all you need.  Change to 6m or 10m when signals are marginal and I run about 400 watts.  I will only get a -10 from the distant DX too.  with 20w that contact would never have occurred.  The DX would have never heard me.  I tried 20w and yes on a crowded FT8 segment on 20m prime time when everyone is awake yes only run what is needed to conduct the contact.  That is what is in part 97, but when I am working an ATNO the Pacific Island on 17m at 2am local time I am gonna give it the whole 9 yards.  Do keep in mind that KH1 will be running DX mode and to "stop an arms race" they will supposedly be using the max signal level put in the program by K1JT.  So in this case your gonna want start low and work up in power because if you blow their ears off with >+10 the computer is going to ignore your calls.  Note: I have been +10 with 20w to ZL and I have been -17 with 450W.
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Roger J. Buffington

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Lin, that is what I am saying too.  I always try to use the least amount of power I need to get the job done.  During good band conditions, I typically use 25-50 watts.  During the many times that conditions are not so good, more QRO is called for and appropriate.  I was trying to get a European Russian station the other day, which is good DX for us Californians.  Tried 75 watts but ND.  Kicked it up to 300 or so and got him on the next QSO.  Doubt I'd have got him at all without QRO.
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Craig - KØCF

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You really should take a look at the Elecraft KPA500 -- it puts out 600W easily, transmit-receive switching is instantaneous and totally silent, and the amp is very compact and quiet. It will totally automate with a Flex Radio using an FTDI USB-RS232 cable and a null modem adapter on the amplifier end. With this, the amp will automatically band switch. I used one of these for 5 years and it was totally reliable. The only reason I'm not using it now is that I got the new KPA1500! The current price is $2965, including the proper cable for the Flex 6000-series. (I have no connection to Elecraft -- just a well-satisfied customer.)
Craig, KØCF
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The KPA500 also available in kit form for $2100...not much more than an ALS-600s! 
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Bill -VA3WTB

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We know about their amps, but this post is asking about Flex 
witch is preferred.
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Roger J. Buffington

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I agree, Craig, that right now the KPA500 is very close to what I'm describing. I may end up with one.
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Al Dewey

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I am a Flex 6600M and KPA500 user.  Like them both a lot!  One thing I wondered is whether it might be possible to use the KPA500 as an "SO2R amp"?  In other words, does the amp switch quick enough such that, if I had the right cables and switch box, might I  be able to go back and forth between bands on the KPA500 during SO2R operation with my 6600M?  I am thinking that this might not be possible (or advisable) but I was just curious whether anyone has tried this?  I suspect it would be better to just get another KPA500.


Al, K0AD
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Tim - W4TME, Customer Experience Manager

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Not in the near future.  We want to get all of the PGXLs shipped first ;-)
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Bill -VA3WTB

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But, for me, if Flex did come out with a smaller amp? that would be my choice.
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Jon - KF2E

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If they announced it tomorrow you wouldn't see one until 2020. If you want a mid size amp in the here and now look at Elecraft , Palstar or SPE.
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Roger J. Buffington

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Looks like you are correct.  
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Bill -VA3WTB

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Depending how complicated a product is, it is not unusual for a company to take two years from idea to shipping.
In the case of the PGXL there were many stages in design, then the software development that takes a lot of time being a software defined Amp.

I think, if they ever made a smaller amp it would not take as long because of having the big one done. Flex would have a good idea about components and design already.
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Steven Linley

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Just because the amplifier can produce 1500 watts doesn't mean you have to use it at that level. But it's very good to have plenty over build for reliability. I have a RF-Kit B-26 RF 2K+ fully remote four antenna output, Auto Tuner, touch screen current price is around $3700 US (2850 euros + $200 3day Fedex, + $120 for parts you buy easily from US suppliers ). More on my QRZ page.

Steven WA8Y
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WW1SS - Steve

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Roger . . . I have a nice Palstar LA-1k I'll sell you . Contact me off list if interested.