[Elecraft] K2 glitch finally found!
Gary Surrency must be the most patient person on the earth. He just emailed me twice within 1/2 hour of my questions. I can now report that I HAVE LCD READOUT! I had to replace all electrolytics on the Control Board to find my error. I found that I soldered C45 (on the bottom of the board) across pads of U6 instead of U8. I missed it on several rechecks because it was new and not listed on parts placement diagrams in the back of the manual. I want to thank everyone who has helped me so far...Don Wilhelm comes to mind. Also, thanks to N0SS for pix of circuit boards. Now, I have a question (of course). My first resolder job was C13 on Control Board was, naturally, the worst. On replacing the cap, I note that the pad is damaged on the negative lead. I soldered over to an undamaged part (I hope successfully). My question: is the negative lead supposed to be directly to ground? (perhaps soldered on the top of the board) I get about a meg of resistance between the lead and ground. Is this a problem? Now to build the RF probe. By the way, I am now a ham again ... after a hiatus of over 30 years. I just passed levels 1 thru 4 in one sitting over the weekend. I didn't expect to pass the Extra but I studied like hell. The ARRL books are fantastic. Couldn't have done it w/o them. So, I'll be able to use a new call sign within a few weeks! John ___ 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
RE: [Elecraft] K2 glitch finally found!
John, Yes, 1 megohm of resistance to ground for the negative side of Ctrl Bd C13 is a problem, and yes it should be connected to ground. If you have damaged the through-plated hole during your removal techniques, you should connect the lead to ground somewhere on the back of the Control Board - adding a wire to the center leg of the 8 volt regulator would be a good way to do it - because soldering the capacitor on the component side of the board would be most difficult - that capacitor will be responding to lower frequency noise rather than HF, so a moderate length added wire should work just fine. 73, Don W3FPR -Original Message- ... Now, I have a question (of course). My first resolder job was C13 on Control Board was, naturally, the worst. On replacing the cap, I note that the pad is damaged on the negative lead. I soldered over to an undamaged part (I hope successfully). My question: is the negative lead supposed to be directly to ground? (perhaps soldered on the top of the board) I get about a meg of resistance between the lead and ground. Is this a problem? ... ___ 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
