Hi As you describe your problem occurring with the side tone as well as the received signal I would suspect something in the AF amp circuit. Look for a bad connection, missing or wrong part around U9 on the control board. If you cannot find anything U9 may be bad. If you need to replace U9 cut all of the pins next to the body. Then using tweezers or needle nose pliers remove each pin while heating the pad. Clean out the holes with a solder sucker or tooth pick and then install the replacement IC.
Don Brown KD5NDB ----- Original Message ----- From: Maxwell Moon<mailto:[EMAIL PROTECTED]> To: Elecraft List<mailto:[email protected]> Sent: Tuesday, August 24, 2004 10:06 PM Subject: [Elecraft] K-2 Audio problem Hello, My K-2 audio sometimes fades completely away. It can happen whether I'm in RX or TX mode. (Yes, the sidetone can fade to faint or no signal.) Sometimes the audio comes back up almost to the original level, sometimes even all the way back. But it fades again before too long. And it happens with an external speaker or headphones, too. This doesn't happen when I've just powered up. In fact, it's probably always more than 15 or 20 minutes but I've never remembered to note the exact time. If the audio stays weak, I can almost always recover it by turning the AF up until the audio makes an odd sound, sort of like a bubble bursting. I may have to rotate the knob to the 3 or 4 o'clock position, and sometimes I go all the way & it still doesn't come back. But after it's back, it stays that way for at least a few minutes. The serial number of my K-2 is 9xx (I'm not being discrete or protecting my privacy--I just can't remember & don't want to climb the stairs to check on the rig itself ;-) It's a CW-only rig with the I/O, 160M, & NB mods. The filter cases were grounded, filters aligned with Spectrogram, & several other mods completed last year including installation of the speaker grill cloth (you don't suppose *that's* the problem, maybe the fabric has too tight a weave for the sound to get out??). Well, that probably tips you off to my level of RF sophistication. So, if any of you can suggest what I should check or look for, I'd be very grateful. 72, Max, k0max _______________________________________________ Elecraft mailing list Post to: [email protected]<mailto:[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<http://mailman.qth.net/mailman/listinfo/elecraft> Help: http://mailman.qth.net/subscribers.htm<http://mailman.qth.net/subscribershtm> Elecraft web page: http://www.elecraft.com<http://www.elecraft.com/> _______________________________________________ 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
