"Ken Scharf" wrote in message
. ..
Yes I built a similar oscillator, a bit cruder though
I clipped my scope probe to the output and connected the
probe to the counter. I noticed that the frequency drifts somewhat
when the crystal is first plugged into the test oscillator. I
guess I need to let the frequency counter warm up for about a
half hour before taking any measurements, the oscillator may
also need a warmup period, and perhaps even the crystal.
If you handle the crystal while inserting it into the socket
the heat from your hands probably affects the crystal, though
I noticed that if I continue to hold the crystal with
two fingers things stablize more quickly (is my hand acting
as a crystal oven?) Total drift is under 250hz.

I used an untuned buffer. Listening on a receiver when I connect the
counter, I hear no pulling. Sounds like your counter needs an oven! Based on
what you're saying about hand temperature moving the frequency, I am
expecting to see an article on passband tuning using a lightbulb driven by a
variable regulator, mounted next to the filter and BFO xtal. "Passband
Tuning Via Thermally Induced Piezoelectric Deformation."

73,

"PM"