Great advice, Don. I will try that soon. The noise is raspy alnost static like. Not a ticking like you would expect from digital noise.
I have mechanically probed every component lead and cant cause the noise that way which I would expect from any intermittant connection. Nor does rapping hard on the case cause it. It simply repeats at its own pattern rate: 1/2 sec burst, 1/2 sec pause, 3 sec burst, 8 sec pause, endlessly repeating. 73, Bob, WB4SON On Tuesday, December 29, 2015, Don Wilhelm <[email protected]> wrote: > Bob, > > Can you describe "noise burst" - is it more of a "tick", or if it is > longer, what is the approximate duration. > You will likely have to short the signal path at several points to isolate > it. One such point is the input to the product detector - solder a jumper > between pins 1 and 2 of T2. If it disappears, you will have to look > further toward the antenna - jumper from the base of Q3 to ground (or > between pins 3 and 4 of RP6). > OTOH, if it is still present with the jumper across T2, the next jumper to > install is between pins 2 and 3 of U3 (which should do the same as when the > K1 is muted). > > 73, > Don W3FPR > > On 12/29/2015 12:35 PM, Bob wrote: > >> Thanks for the ideas, Mike! >> >> Well I can rule out the Filter Board, as the noise is still there when the >> Filter Board is removed. >> >> I hoped I could remove the CPU to see if there was an issue there, but >> with >> the CPU gone, the audio is eliminated (probably need to pull something >> high >> or low to get the audio back). >> >> >> > ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html Message delivered to [email protected]
