On Sat, Jan 16, 2016 at 7:58 AM, Hans J Rasmusen OZ7BQ <oz...@yahoo.dk> wrote:... > The output and SWR green LED status indicators on my KX3 (sn 18xx) > KXPA100/KXAT100 (sn 08xx) combo exhibit some unusual behavour on 40 Meters > CW... > The above problem appears to be RFI related, as the jumping output/SWR > indications are present only when feeding an antenna. ... > My questions are:Has anyone experienced anything similar?....
I experienced similar problems on 40m with my K3+KPA500+KAT500, i.e. the SWR would suddenly jump, the amplifier would fault, and the automatic band selector antenna switch would chatter. Because the problem only seemed to occur on 40m, I investigated the antenna, found a loose connection, but it did not fix the problem. Eventually, similar fault occurred on 20m. Finally, I found that the short coaxial cable between the KAT500 and the antenna switch was intermittent. I could observe change in receive signal strength when I twisted the cable, near the PL-259 connector. Substituting a different cable has completely fixed the problem. I suspect a bad soldered shield connection in the bad cable. At one point, while investigating this problem, receive sensitivity on 40m only, was 30 dB worse, although transmit was normal. The RX_ANT had been activated, and there was no receive antenna connected! -John AC6SL ______________________________________________________________ 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
