Hi, I'm Sarah, AF6FH! I just got my license a couple weeks ago, and I'm now assembling K2# 0622, which will be my first HF radio. I started assembly on Wednesday night, and so far, everything's been going just fine.
But... I'm having a little issue with setting the AGC Threshold. The instructions (pg. 48) say to set the RF GAIN control fully clockwise, measure the voltage on pin 5 of U2 on the control board, and adjust trimmer R1 for a reading of 3.80 volts. I did my voltage measurements with my own (cheap) DMM, not the internal voltmeter. My concern is that, by adjusting R1, the highest I could get the voltage to go was 3.59v, so for the moment, that's where it's set. I measured the voltage on the LM29307-8, and it has 12.23V at the input, but only 7.53V at the output. The 78M05 has 4.93V at its output. When I rotate the AF GAIN control, I get a range of 4.68V (fully counter-clockwise) to 3.59V (fully clockwise) on pin 5 of U2. My power supply is a small benchtop power supply; it's putting out 12.4V, and reports the K2 is drawing about 100mA. When I measure the input voltage across the K2 input jack, I get the same 12.4V. All of the previous checks were fine, and the following step, S-Meter Alignment, seemed to work just fine. So, my question is, do I have a problem? Should I be concerned? Thanks, Sarah AF6FH _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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
