[Elecraft] K1, what is wrong ?

[Don Wilhelm]

  Charlie,

The hum and the popping may or may not be related.  I cannot comment on 
the popping other than to say it is not normal.  A 'scope would be handy 
to look "backwards" through the receiver chain to see were it originates 
(sort of like reverse Receive Signal Tracing).

On the hum, do you have anything within a 2 foot proximity of the K1 
that has a AC transformer (linear power supplies should live under the 
operating desk rather than on it IMHO).  It is possible that a 
transformer's magnetic field can couple into the K1 and modulate the VFO 
inductor.  Try removing the K1 from any AC magnetic field, and test it 
on a battery if possible (an automotive battery will work just fine, 
even  while still installed in the vehicle).

73,
Don W3FPR

On 4/25/2011 3:17 PM, CHARLES WHITE wrote:
> I recently completed the assembly of a K1 Sn#2905.  I really cannot tell if the thing works as there is an irregular but frequent and rather intense popping that is cannot determine the cause.
>
> This occurs with just the rf  board and front panel installed.
>
> The panel keys appear to function and all else seems to function.
>
> I have check and recheck part placement and every solder connection.
>
> I also have the uncomfortable 60 cycle hum that I can control by shifting the K1 around into different positions.  I use the power supply for a K3 without any problem.
>
> Any suggestions?
>
> Thanks,
>
> Charlie White
> K6TBB
> San Diego
>