I mentioned my broken frequency counter... Tony Fishpool, G4WIF, of G-QRP sent me a replacement CMOS chip. The counter is now counting beautifully. It was a real chore to get the bad chip off the double-sided board, then I doubled my work by putting Tony's chip in upside down. It doesn't work very well that way. I did another chip extraction. By this time I had all kinds of lifted pads, broken traces, pins on the verge of breaking. I felt sure that all the heating and de-soldering had destroyed the CMOS. But no! It lives!
This was a very satisfying troubleshoot and repair. I feel like Dr. House. The whole thing was made even nicer by the fact that the repair part came from the junkbox of a friend. Thanks Tony!
Looks like the old counter is still well-calibrated. It has my QRSS sig at 10140070. ON5EX's grabber puts me at 10140050. So the counter is 20 Hz high. Not bad for flea market junk.
Saturday, January 24, 2009
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Congratulations Bill.
ReplyDeleteIt is always satisfying to troubleshoot a problem and find the solution. Although, I know how you feel when you put the chip in wrong! It is kind of a way to humble us so we won't think we are too great. :) I know what was going through your head. "Oh, man! What a duffis!" Been there, done that. HI
John - K7JM
Thank you for putting the chip in upside down, and thank you again for tell us. Just last night I put a 2N3904 in backwards, so it is really nice to see that I'm not the only one!!!
ReplyDeleteJer