Did you find your problem? Any fault codes? I suggest contacting supp...@elecraft.com, but if were me, I'd check all internal connections first and do a quick visual. I suspect a problem with the elaborate TR switching circuit or something that controls it.
I see a couple 51 ohm resistors on the schematic at the input to the PA module, so if the TR switch was working, I would NOT expect hi reflected power to the rig with no power out of the AMP. Joe Hutchens ( AJ8MH ) http://webpages.charter.net/aj8mh-radio/ On Fri, Sep 21, 2012 at 8:01 PM, Phillip Shepard wrote: > I put my new KPA500 (s/n 1057) together earlier this week and have > been > loving it, although it has seen only light use so far. > > However, that changed this afternoon. I used it briefly on 40m LSB a > few > hours ago and all was fine. About 35w of drive for 550w out. I just > retuned the antenna to the low end of the band, yielding a 1.0:1 SWR > at the > K3 in the standby mode of the KPA500. When I switched the amp to > operate > and keyed the transmitter (tune control), the amp power LEDs jumped up > to > about 500w and then went to 0. Subsequent keying show a very high > SWR at > the K3 (65 to 99:1) and the K3 puts out no power as does the KPA500. > I > tried a dummy load with the same result. If the amp is in standby > mode the > K3 acts right and the power and SWR LEDs on the KPA500 act right (100w > out > at a low SWR). Putting the amp into operate mode acts like the input > SWR is > very high. > > I tried tightening up the cables at both ends (BTW, I am using the > control > cable between the rig and amp for maximum integration, and the K3 > knows to > reduce the power out when the amp is in operate). > > I hope I am doing something wrong, and the fix is simple. Any > suggestions > of where to begin? Thank you. > > 73, > Phil, NS7P > > ______________________________________________________________ > 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 ______________________________________________________________ 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
