[Elecraft] K2 EXTERNAL VFO CONTROL

[VR2BrettGraham]

G4BUE asked:

>Has anyone built an external VFO for the K2, please?
>
>I took the plunge last Sunday and sold my UK main station
>transceiver, a Ten-Tec Omni VI, and have replaced it with one of my
>K2s.  I am now an all Elecraft K2 station at both my UK and at my
>Florida QTHs (SO2R in Florida and shortly SO2R in the UK).
>
>The only thing I miss with the Omni is the external VFO control (Ten-
>Tec model 301) and wondered if anyone has built an external VFO for
>the K2?
>
>Perhaps one of our technically minded members on the Reflector can
>tell us if it would be possible and/or very difficult to build such a
>control for the K2, possibly from Elecraft spare parts?
>
>I found a short thread in the Reflector Archives in July 2000 about
>it but without any firm conclusions.
>
>I didn't realise just how much I have come to use and depend on the
>external VFO of the Omni, especially in contests, until operating
>without it this week!

If you don't go too far & keep the lines clean, it will work.  You
need to switch between the two encoders, however.

Looks like the V- lead of Z1 is used to implement dial lock, so
the external knob can have its own local lock & you only need
to deal with the two encoder lines & power, if K2 encoder's
lock is used as trigger for enabling & switching to external
encoder.  If encoder isn't plugged in, K2 still stops tuning when
locked - seems easy... probably forgot about something.  ;^)

73, VR2BrettGraham


73, VR2BrettGraham