slyvania roundie

[earlyfilm]

Originally Posted by DaveWM

One last little issue, seems like I often have to change the channel back and forth when the set is 1st turned on or even if I just switch signal source.

The screen will black out, sound is still there a bit weaker but there. one flip back and forth and all is good.

Try this theory on for size:

Horiz drops sync and the keying pulse hits the signal in the wrong place and this confuses the AGC.

The noise from channel flip wakes up the AGC.

This could be and probably is related to the problem with line pairing and signal level shifts.

Recheck resistor values, especially the high value ones in the AGC and any caps for leakage, where a signal from a higher voltage source is fed into the AGC (or to sync circuits.)

(Warning: With that said, I am not familiar with this model set and have not seen a schematic.)

James