Quote:
Originally Posted by Jon1967us
Yeah, that kinda just started happening... 
When we're talking heater leakage, I thought we're concerned about leaking into the Cathode. Could it be leaking into the grids? I've already subbed out all the tubes, and this makes no change.
Not sure what else there is to do other than modding it by adding the ballast resistors from the Sams.
Just about every relevant component has been changed. The remaining original resistors are within tolerance. |
It's the .2v AC on the cathode of your sync/DC restorer tube that worries me. It stands to reason that same AC is then present at pin 2(grid) of the CRT? When it's doing it's hula, what if any AC do you measure on pin 3(cathode) of the CRT? As an experiment you could hang a few uf's cap alternately from pin 2 or 3 of the CRT to ground to see if that clears up the hula. Observe polarity of whatever DC you measure on those pins to ground. Of course you won't get any video with the cap on pin 3 of the CRT, but at least you'll find out if there's AC modulating the signal there. Somethings got to give.