RetroHacker
10-31-2009, 08:36 AM
I know, I know, I've been away from the hobby for a long while (shame on me). Things got busy and I got carried away with other hobbies - frankly, I got a bit burned out on TV's. Too many sets needing too much work, and I was never able to find the elusive "daily watcher" I wanted. Every set I ever find is in such bad shape - and that wears on you after a while.
But, anyway, I did acquire this one later model Philco roundie. It's one of the very last round color sets, I think, complete with a neat side view tuning eye.
Anyway, when I got the set, it displayed only a purple-tinted black and white picture. I replaced a cap in the color demodulator circuit, and got color... sorta. Red and blue, but no green. I had tested the tube then, found that the green gun gave me no reading at all, and pretty much put the set in the corner.
So, I dragged it out again today. Hooked up the tube tester again, still no green (guess it doesn't get better by sitting for a year). I carefully desoldered the three pins associated with the green gun, and reflowed them with fresh solder - hoping there was simply a bad connection between the tube pins and the feedthrough wires to the glass. Hooked up the tube tester again, and... still nothing. Nada. Zip. Can't get any reading from green. I tried the Clean/Balance function and gave it a zap - no effect. In desperation, I clicked over to Rejuvenate and tried a bigger zap.... And still nothing.
I've never seen a gun in a tube so dead that it won't produce any reading at all. Generally just real, real weak ones. I can see inside the tube and tell that all three filaments are lit - so that's not burned out at least.
The only thing I can think of is that perhaps one of those wires has broken inside the tube base - between the pins and the glass. Or, perhaps there really is something wrong with the green gun, and it's dead. I don't know. Has anyone successfully removed the base from a picture tube, and reinstalled it? I tried once on a dud 5U4, and even on that simple tube, was not able to get the all the wires unsoldered cleanly enough to get them to slide out of the pins. Of course, in that case, I really just wanted the tube base - but here I'd need to salvage both.
Any suggestions?
-Ian
But, anyway, I did acquire this one later model Philco roundie. It's one of the very last round color sets, I think, complete with a neat side view tuning eye.
Anyway, when I got the set, it displayed only a purple-tinted black and white picture. I replaced a cap in the color demodulator circuit, and got color... sorta. Red and blue, but no green. I had tested the tube then, found that the green gun gave me no reading at all, and pretty much put the set in the corner.
So, I dragged it out again today. Hooked up the tube tester again, still no green (guess it doesn't get better by sitting for a year). I carefully desoldered the three pins associated with the green gun, and reflowed them with fresh solder - hoping there was simply a bad connection between the tube pins and the feedthrough wires to the glass. Hooked up the tube tester again, and... still nothing. Nada. Zip. Can't get any reading from green. I tried the Clean/Balance function and gave it a zap - no effect. In desperation, I clicked over to Rejuvenate and tried a bigger zap.... And still nothing.
I've never seen a gun in a tube so dead that it won't produce any reading at all. Generally just real, real weak ones. I can see inside the tube and tell that all three filaments are lit - so that's not burned out at least.
The only thing I can think of is that perhaps one of those wires has broken inside the tube base - between the pins and the glass. Or, perhaps there really is something wrong with the green gun, and it's dead. I don't know. Has anyone successfully removed the base from a picture tube, and reinstalled it? I tried once on a dud 5U4, and even on that simple tube, was not able to get the all the wires unsoldered cleanly enough to get them to slide out of the pins. Of course, in that case, I really just wanted the tube base - but here I'd need to salvage both.
Any suggestions?
-Ian