[Collins] KWS-1 Crystal problem

[Jim Brannigan]

I agree with the other post.  Check all the component values and if OK order
from Int'l Crystal.
I have a 10M JAN crystal in my 75S-3B that is 25kc off the marked frequency.
Int'l Crystal 455kc's in the RX and 32S-3 are right on and provide plenty of
drive.
Jim


>
>
> "Dx. Gxxxxx X. Jxxxxxx, exxxxxxxx exxxxxxx" wrote:
> >
> -------- Entire Content deleted by authors requirement due to being
> copyright material :-)
> >
>
> Further on this problem:
>
> First off, I have received the crystals back from JAN after their
> testing and I am still unable to get them to function.
>
> The one thing I haven't tried yet is swapping the oscillator tube as
> several suggested, which I will try tonight, however what I hadn't
> mentioned previously is that at the very start I had swapped the
> original 12.5mc and 13.0mc from the 10 LO position and 10 HI positions
> and peaked them up to see what would happen. Sure enough, I was able to
> get the 12.5mc crystal to oscillate correctly in the 10 HI position
> (with the appropriate change in dial frequency of course) and with the
> same 1.1 volts of drive I got when it was located in the 10 LO band
> switch position, and the 13.0 crystal oscillated in the 10 LO position
> position at the same .1 volt level I achieved when it was in its
> original 10 HI position. In swapping crystals, it only required a couple
> turns of each plate inductor to get the circuit to peak with the
> alternate crystal. Again, neither new JAN crystal would kick off at all
> in either crystal position.
>
> The fact that the drive voltages follow the crystals, kinda gives me a
> warm feeling that the circuit components themselves are pretty close and
> is what led me to my original conclusion that it was the 13.0mc crystal
> itself that was "weak".
>
> Even if the circuit components were out of spec, I would at least expect
> the new crystals should function somewhat since the original crystals
> seem to work.
>
> Still searching for clues.......
>
> 73, Ray  W2EC
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