R
Rich Grise
- Jan 1, 1970
- 0
Indeed this is a working fix, as I verified on the bench.
Actually in my particular case it appears that the UHF parasitic starts
first. But probably just the luck of the bias point.
Check for dynatron oscillations; the screen acts as a plate, sort of.
http://en.wikipedia.org/wiki/Dynatron_oscillator
I can't find a schematic of one, but it's just an oscillator with feedback
from the screen to the grid.
How long are the leads of your screen bypass cap, and where are they
soldered down?
Thanks,
Rich