Quote:
Originally Posted by Tom Albrecht
It does indeed happen with brand new ASC brand .0047 uF 6000 V tubular capacitors.
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Interesting and completely unexpected!
In the late 1950's, some of these electrostatic sets that had been retired, were wanted each fall by college students going off to school, so their parents would bring them into the shop to be serviced.
We used to see this problem on many of the sets, but not nearly as bad as your pictures show. We tried capacitor* replacement, but we saw no change. The thinking back in the day, was this was caused by the CRT's going gassy and generating secondary emission from the deflection plates. This was sorta confirmed by many of the sets picture improving somewhat after a few weeks of use.
I am at a complete loss to explain how if this were from a gassy tube, why the heck it would cause this symptom on the vertical sweep and not on the horizontal?
James
* (Black molded Sprague caps were used for testing that looked like the RMA banded ones, but were ink stamped and the black plastic was not as shiny.)