[Elecraft] [K1] Internal Noise Bursts every 12 seconds or so

[Don Wilhelm]

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).
>
>