[Premium-Rx] WJ 8617 Synthesizer Problem (?)

[Rye Gewalt]

I'm wondering if anyone on the list had any experience with the synthesizer
in the Watkins Johnson WJ8617?

 

I have a lovely B-17 model that has suddenly lost the ability to tune in
anything under 1 MHz steps.  The display shows the full frequency and all
other functions seem to be working so  suspect that the problem is
associated with the second LO --- probably out of lock.  In fact, the radio
is kind of 'drifty' in that when I listen to signals at the 1 MHz  steps --
I can hear them drifting around as if the VCO is not being disciplined, but
is running.

 

Perhaps one of you have had experience with such a fault or could point me
to somebody who might be helpful.  I've got the manual and all (most?) of
the extender cards etc. and a pretty good shop but, I'm kind of reluctant to
dig into the radio until I've checked with the experts to see if this is a
problem that has a known fix methodology.    --- no point in reinventing the
wheel and maybe screwing up something else in the process...

 

Any help would be greatly appreciated.  

 

In the meantime, I will spend some time checking supply voltages etc.

 

Rye