During the 2009 CQWW CW contest, I got a report of severe chirp from one of the stations I worked.
I turned on my OMNI 6 to listen to my signal and there definitely was a bad case of chirp. I confirmed this on 15 meters, 20 meters, and 40 meters. 80 and 10 showed no issue. External KW amp on or off did not make a difference. I use the K3 12VDC OUT port (0.5 A MAX Switched) to drive antenna switching relays and the control circuit (CMOS BCD to decade decoder) that is driven from the K3 ACC port. To solve the chirp, I used a couple of clamp on ferrite cores on BCD output from the ACC connection AND the 12 VDC OUT. Remove the cores, the chirp returned. I have not yet tried to separate the BCD signals from the 12 power to determine if suppression is necessary on one or both. FYI Lee N8LJ ______________________________________________________________ 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
