"Just Another Theremin Fan" wrote in
ups.com:

Also CALIBRATOR sync is not
rock solid but was previously. Possibly 60 HZ is disturbing SYNC???

Is this the rather elderly 200MHz DB jobbie? I ask as my one (wherever
it is) Has always given out 900Hz from the calibrator rather than 1kHz.

Becasue it's only an AMPLITUDE calibration signal *for probe compensation*.
The only TEK scope that had a accurate frequency calibrator in that era was
the 7704A with a special option(rare).It was Xtal controlled.The digital
scopes have more accurate cal signals,WRT timing.


On the rare occasions that I use it, I sometimes find that the front
rotary switches give all sorts of oddball problems which a clean
usually resolves.



Because the HF(and LF) cam switch contacts have a very low wiping force and
are vulnerable to airborne contaminants,plastic outgassing mainly.

--
Jim Yanik
jyanik
at
kua.net