[Elecraft] K3 Tuning encoder pulses and birdie problem

[David Gilbert]

With my K3 terminated in a dummy load and the preamp off, I can just 
barely hear the decoder pulses.  I checked it in both CW and SSB, and I 
set both modes to 1 KHz bandwidth and adjusted the shift for the same 
center frequency of 600 Hz.  With the preamp on they are more 
noticeable, making the S-meter briefly tick up to about S2 if I tune 
quickly.  When I stop tuning, of course, the pulses disappear so I'm not 
sure they would ever actually hinder me from making a QSO.

Here's an interesting quirk ... possibly just my imagination but I don't 
think so.  I have the subreceiver installed, and if I engage it so that 
I can simultaneously hear the main receiver in my left ear and the 
subreceiver in my right ear, tuning the subreceiver across 28005 creates 
louder decoder pulses in the main receiver than it does in the 
subreceiver.  Then again, I have never found as many birdies in the 
subreceiver as I have found in the main receiver, and those I've found 
in the subreceiver are at least ten db weaker than their main receiver 
counterparts.

I do not hear any birdie at that frequency, though.  If I listen very, 
very hard with the preamp on, I can hear a tone just under the 
background noise, but I have to tune the VFO to hear the changing pitch 
in order to detect it.  Without the preamp on, it is impossible to hear 
it at all.  It isn't a birdie, though ... the pitch changes smoothly and 
slowly as I tune across it.  I have found (and removed via SIG RMV) a 
few other birdies on 10m, on my rig 28005 isn't one of them.

I do believe that tuning artifacts vary quite a bit from K3 to K3, 
though, so you may be experiencing a much greater problem than I am.  If 
so, you may want to consider making an audio recording of it so that the 
rest of us can hear it.

73,
Dave   AB7E




Jan Erik Holm wrote:
> When 10m opens up this will be a serious problem.
>
> On 28005 KHz a quite strong birdie carrier, on
> each side of this carrier there are "tuning pulses
> generated from the encoder in the segment 28000 to
> 28010 KHz. All this gets stronger with Preamp ON.
>
> Is it only my K3? Or is this on all of them?
>
> Any solution?
>
> This internal carrier might be removed with the
> new FW but any solution for this tuning puls
> problem.
>
> 73 Jim SM2EKM
>
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