|
Brightness solved
Turned out not to be too much positive voltage but, not enough negative. Someone replaced two resistors R-64 and R-135 (Sams) with values that in total equated to three times the original value. There was not enough negative voltage getting to the brightness control to pull it back enough from positive, thus the sky high grid volts. One of these was on a terminal strip on the top rear of the chassis. This was a factory location but seem like an odd place for it.
Next stop is the seemingly high Horiz cathode current @225 ma. Sharp dip when adjusting the eff coil and drive and grid bias is good. May be possible aged transformer that will have to be tollerated.
|