[Elecraft] Isolating the KPA100 External Keying Line

[Vic K2VCO]

Roy Morris wrote:
> When keying my Alpha 99 via a shielded cable from the KPA100 J7 jack,
> there is a small amount of stray RF getting into the SSB signal.
> This RF is not present when the amp is used with either my 756 PRO2
> or 706MK2G, and it is not present when using the K2 at 100 watts
> barefooted regardless of band or mode.  

How do you know it's RF?  Maybe it's the magnetic field from the big 
transformer in the 99?  K6SE claimed that he could hear hum modulation 
on my signal when I operated my (unmodified) K2 3-1/2 feet away from an 
Alpha 86.

You might try temporarily moving the amp farther away from the K2 or 
getting the VCO magnetic shield mod from Elecraft.
-- 
73,
Vic, K2VCO
Fresno CA
http://www.qsl.net/k2vco