17Mc crystal (was RE: [R-390] Strange modulation on carriers)

[David Wise]

> -----Original Message-----
> From: r-390-bounces at mailman.qth.net
> [mailto:r-390-bounces at mailman.qth.net]On Behalf Of Tim Shoppa
> 
> FM'ing of the 17 Mc oscillator, with the deviation
> strongly correlated to the AGC action (thus you noticing
> it as you tune through the calibrator), is commonly
> noted. In my experience it is a few hundred Hz
> in the "bad" cases but maybe it's more or less for you.
> 
> It is partly a design flaw but for example a flaky
> 17Mc crystal will be more pulled than a good strong
> 17Mc crystal. This is probably at least one of the
> reasons why surplus 17Mc crystals are hard to find!

Just to fill in some background, I believe that this is
mentioned in the Cost Reduction Report.  The maximum
frequency of crystals of the desired characteristics
had just passed 17Mc.  They didn't want to use it, but
other considerations won.

I'm working from rotted-out memory here; if anyone
knows the story more correctly, please follow up.

73,
Dave Wise