[Elecraft] Hum Coupling

[Earl W Cunningham]

Fraser, G4BJM wrote:

"Interesting - I had complaint on air recently of having a wide CW
carrier when using a tube linear about two feet from the K2/100."
==========
Exactly the problem.  Rather than hum, it sounds like noise on the
sidebands of the signal -- becoming less broad as the distance between
the K2 and the amp increases.  This is easily heard when you monitor your
transmitted signal on another receiver.  The K2/100 is absolutely clean
barefoot.

Perhaps the field from a hypersil xfmr is greater than a "normal" xfmr. 
Both Alphas I have tested my K2 on, at home and at a friend's QTH) have
hypersil HV xfmrs.

I even removed the KPA100 and ran my 10-watt K2 into the amp with the
same noisy sidebands occurring on its CW and SSB output.

There IS a problem!

73, de Earl, K6SE