[Elecraft] K3: cw xmiting 2 signals 600hz apart: HELP

[Geoffrey Mackenzie-Kennedy]

Hi Doug,

This certainly happens with the K2.

The cause in the K2 case is that the CW sidetone oscillator signal gets into 
the VCO's varicap circuit and frequency modulates the VCO. The sidebands 
that I can see coming from my K2 in CW mode are symmetrical above and below 
carrier, one pair about 90db below carrier and the others much lower in 
amplitude. Their level varies with band.

73,
Geoff
GM4ESD


DOUGLAS ZWIEBEL wrote:

> Hi everybody...
>
> I local K3 owner received this memo and forwarded it to me this
> morning for my opinion:
>
> <When you were working HA5JI, you had a side band about s6 up about
> 600 Hz.  I did not check the down side. Your main signal was s9+20.>
>
> I was at work so I said I would listen when I got home (we live about
> 3 miles apart).
>
> On 160m (where he got the notice), his signal sounded fine barefoot,
> but with the amp on, I could hear it also.  So I asked him to qsy to
> 40m where he is about 25db over 9 on my K3.  And as I tuned off of
> him, I could hear the "second signal" as described above.  The 2nd
> signal tunes in the same direction as the real signal (it is not blow
> by).
>
> Any comments or even better, any suggestions for him?
>
> Thanks,
> Doug KR2Q