Hello again folks, I seem to still have that black cloud hanging over me as I finish the basic K2 #5061.
I am finishing the calibrations and adjusting the L's and C's in the bandpass filter section. I had 1 1/2 problems remaining. All the circuits tuned properly in receive mode except the 30 meter/20 meter bandpass filters. They would not resonate no matter how I screwed the slugs in or out or adjusted the trimmers on 20. I took the unit to an engineer friend (K4POZ, who retired from chief engineer for WSB radio in Atlanta) and he verified that I had assembled the circuits correctly and had no solder splashes or missed connections. (He recently completed his own K2) He noted that when the slug on L9 was all the way in, the signal started an ever-so-slight increase in output. Figuring the circuit was resonant too high, he added a 39 pF cap across L9 and the signals could then be properly tuned on 30 meters. The trimmer C23 rotor plate had come disengaged (popped out) as I had attempted to tune it earlier and a new one was sent by parts. I anticipated that would solve my last problem but to no avail, so 20 meters is still down about 70 dB or more. I rechecked all components in the circuit and all are installed correctly. Has anyone ever seen this problem before? Suggestions? By the way, I solder filled all the through-holes around this circuit just in case there was a poor plate-through feed. No change. 73, Pat Haynes-K4BEH _______________________________________________ Elecraft mailing list Post to: [email protected] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
