Quote:
Originally Posted by jr_tech
"While taking that photo in total darkness, I noticed the 25L6 driving the flyback glowing blue. Should I be concerned?"
To me, the blue glow looks like one would expect from electrons striking the glass of the tube...it is at the internal surface of the glass, right? and not inside the tube structure between the cathode and plate (that, I might take to be an indication of a gassy tube).
Have you tried swapping the caps back one at a time to determine if it is the 100 pf or the 250 pf That is causing the problem?
Incredible job, I would never have attempted to restore a set that is that far gone...Standing ovation from here!  |
Thanks! Now that it's actually showing signs of life, it's a lot more fun to work on.
Yes, it's the internal surface of the glass that's glowing. It's the side facing the HV cage. It's a NOS tube, but I suppose it could still be gassy. I'm also wondering if the nearby HV or grounded surface could be affecting it. I'll try swapping it later tonight when it's nice and dark.
Very good point about those caps. I'll try swapping them one at a time. I've got some others to try as well. I did a little thinking while at work today and it occurred to me that the voltage on those caps might very well be exceeding 500v at the peak of the sweep voltage.
Maybe one of them was breaking down and conducting causing the clip with those 500v micas?