Interesting. In my case I never resolved if the MC1350 actually was bad. I soldered the entire assembly out of the circuit, but managed to find an original "full size" chip at a local store, put it in and it simply worked. So, the problem - whatever it really was - might have been the same as yours, and the SMD assembly might have worked if I had put it back into the rig the second time.
At any rate, good that you are on track, and hope others may learn from this. My K2 (#6425) is working perfectly, aside from the fact that my 8V is low (about 7,56V), and as a result the S-meter can not be calibrated properly. I will ask Elecraft to send me a new regulator. 73 and good luck! - Kristinn, TF3KX Are LB3SA wrote: > > It was actually one of your earlier posts (thanks!) that prompted me to > inject the IF signal before and after the IF Amp. At that point I had > pulled out lot of hair and lost sleep over a low sensitivity K2. > > As to when the solder bridge got there... I'm not 100% certain that a > bridge was the problem. But after I realized that the IF Amp was not > amplifying I went over the solder points around the chip (I actually > removed the chip and installed it again). The radio then started to work. > It was actually a bit of a surprise since I never saw the problem - > especially since I looked very closely at all the points through an > amplifying glass many times before AND since all the voltages at MC1350 > measured at specs while I had the problem. It was just the IF signal that > wasn't amplifying leading me to at first think that the chip itself was > defect. > > I only assume it was a solder bridge. And if that's the case it was > probably made by me. > > Are - LB3SA > > > > TF3KX wrote: >> >> Just out of curiosity... >> >> Where was that solder bridge on the MC1350? Was it already on the SMD >> assembly when you received it, or was it something you caused by your >> soldering? >> >> The reason I ask is that I had a problem with my SMD MC1350, never found >> out what caused it, and just replaced it. If there is something there to >> watch out for, it may help others... >> >> 73 - Kristinn, TF3KX >> > > -- View this message in context: http://www.nabble.com/K2---signal-loss-in-band-pass-filter-tp17294418p17630518.html Sent from the Elecraft mailing list archive at Nabble.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
