Beltron 8081A filament adjust pot

[jeyurkon]

If anyone has a schematic for a Beltron 8081A could you please look at it and see what value the filament adjust potentiometer should be?

I purchased an 8081A off of ebay and it appears that someone worked on it previously. The filament adjust is too twitchy for me to risk using it. The pot installed is a 20kohm one. The regulator is an LM317 and the program resistor appears to be 240 ohms so I wouldn't expect you'd need more than 3,600 ohms from the pot to get 20 volts. I would think they probably had a 5kohm originally.

It only takes a small fraction of a turn to get 20volts out of it now. I don't want to risk burning up a CRT with the way it is currently.

John Y.