Yes that's my experience to. I get much better IMD at 20W than at 12 W. It would be better if the KPA3A, if present, was used for anything above 10W.
/Johan, SM0XHJ On Thursday, 29 March 2018 14:39:49 CEST Wes Stewart wrote: > Doubt that. From what I've gathered during a lot of TX IMD testing on my > original K3 and my K3S, with several (lost count) different LPA and HPA > modules, it's a 10W amp. It's allowed to go to 12W but that's a really, > really bad idea, from an IMD standpoint. IIRC it's been asked that this be > "fixed" in firmware but it hasn't seemed to be put "on the list." > > Wes N7WS > > On 3/29/2018 4:50 AM, hawley, charles j jr wrote: > > How do we know that’s pushing it? Maybe the LPA is designed for 20 Watts > > and the K3 cuts them off at 12 Watts. > > > > Chuck Jack > > KE9UW > > > > Sent from my iPhone, cjack > > > >> On Mar 28, 2018, at 7:23 PM, "j...@kk9a.com" <j...@kk9a.com> wrote: > >> > >> Instead of pushing the 12 watt PA this hard it would sure be nice (and > >> cleaner) to have the option of using the KPA3A for 10-12 watts output. > >> > >> John KK9A > >> > >> > >> K7TV wrote: > >> > >> I have been testing sustained power capabilities of wideband HF > >> transformers for feeding EFHW antennas. This involves running high power > >> through HF transformers back to back into a dummy load. When running > >> 200W out of the KPA500, the K3 was indicating 12W, and I think that > >> means the 100W PA was not operating. After a few minutes the K3 totally > >> shut down. This had nothing to do with the transformers under test; I > >> get the same result when running the KPA500 at 200W directly into the > >> dummy load. After restart the K3 shows no sign of problem unless the > >> 200W endurance test is run again. Then I increased power just a little > >> bit so that the 100W stage kicked in. I got 300W out of the KPA500, and > >> now the K3 keeps going without shutting down. I can see how 12W may be a > >> bit much for the driver stage, but if so, shouldn't the 100W stage kick > >> in sooner? Also, I expected the K3/KPA500 combo to be able to produce > >> any power level I wanted within its range. What I see is that when the > >> 100W stage kicks in, the output (as seen on an analog meter) makes a big > >> jump so that certain power levels cannot be achieved. > >> > >> Thanks, > >> Erik K7TV > > ______________________________________________________________ > Elecraft mailing list > Home: http://mailman.qth.net/mailman/listinfo/elecraft > Help: http://mailman.qth.net/mmfaq.htm > Post: mailto:Elecraft@mailman.qth.net > > This list hosted by: http://www.qsl.net > Please help support this email list: http://www.qsl.net/donate.html > Message delivered to jo...@e-626.net ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to arch...@mail-archive.com
