I had a similar problem many years ago with an L-4B amp. I wonder if adding ferrite to the coax would solve this problem? GL N2TK, Tony
-----Original Message----- From: Elecraft [mailto:[email protected]] On Behalf Of Jim Kvochick Sent: Tuesday, November 18, 2014 9:16 PM To: [email protected] Cc: [email protected] Subject: [Elecraft] Strange K3 & KPA500 Issues fixed with a longer coax cable? I've stumbled into a strange problem. I have 4 friends with similar K3 stations to my own; K3 >>> KPA500 >>> KAT500. The stations are powered with similar power sources. One station sounds fine, works great. The other 4 had strange issues that manifested themselves as audio distortion when running the amplifier. After looking all over for RF and grounding issues, we swapped the coax cable from the K3 to the amplifier, with a longer cable (about 6 to 7 feet - largely because that was the only free cable we had handy). Making the cable from the K3 to the amplifier longer eliminated the issue. putting the cable back brought the problem back. Making a new short cable still left us with audio distortion. The only thing that seemed to solve the issue in all 4 cases was making the K3 to amplifier cable longer. This got me to investigate my own station. It turns out that the cable I used between the amplifier and the radio was about 6 feet long. Swapping this cable for a shorter length brought about audio distortion symptoms. Does anyone have any thoughts about this? Cheers Jim K8JK ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected] ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected]
