[Elecraft] K3 Hum on Audio...

[Geoffrey Mackenzie-Kennedy]

When the KPA500 is in standby, I assume that its AC mains is still 
connected.  Have you tried pulling the KPA500's mains plug to narrow
the search?

Is your P3 sitting between the KPA500 and the K3?

73,
Geoff
LX2AO

On January 13, 2012, at 18:20 +0100, "Phil Hystad" <phystad at mac.com> wrote:

<snip>

> If I lay my hand on the top of the K3 the hum disappears.  If I lay my 
> hand on the P3 sitting next to K3 the hum disappears but not as much. 
> And, I can do the same with other grounded equipment.  I have checked my 
> grounds and they all seem to be pretty good.

and earlier

>> So, I am thinking maybe it has
>> something to do with the KPA500.  So, I put that in Standby and the hum 
>> is
>> still there on the audio.  The mic is the MH2 hand mic plugged into the
>> front of the K3.