View Single Post
  #11  
Old 07-10-2012, 11:25 PM
Eric H's Avatar
Eric H Eric H is offline
Administrator
 
Join Date: Jun 2002
Location: So. Calif
Posts: 11,565
Quote:
Originally Posted by wkand View Post
Please consider replacing the selenium rectifier with plain silicon diodes. This would be the orange device with the big fins. They have a notorious rep for failing suddenly. Not AS much of a problem in this set since it is series string and there is no pwr xfmr to blow up.
I may, though I've had good luck with Seleniums in the limited use these sets will see.

Tonight I replaced the last Can Filter, all the paper caps are done too.

I also replaced one marginal resistor on the main board.

When I tried to fire it up tonight I had no picture, this was due to having no high voltage though I could hear the oscillator running.

I thought the tube bases might still be wet from washing them the other day so I retested the output and damper, the output was fine but the 12AX4 was absolutely dead, zero emissions and not due to water in the base which would have caused a short reading.
Oh well, I scrounged up another one and back in business, however now the Horizontal wouldn't go far enough to bring the picture in, it would almost make it then the oscillator would start screeching and die.

I found this was due to a drifted 150k resistor on the Horiz board, it was up around 550k. I jumped a 470k across it and now the horizontal will flop both directions, however I still have no Sync, vertical or horizontal.

I guess I will have to remove the horizontal board and go over it carefully, check all the resistors and maybe build some new integrated parts.
Reply With Quote