View Single Post
  #58  
Old 12-31-2018, 06:31 PM
ZenithNut ZenithNut is offline
VideoKarma Member
 
Join Date: Jul 2018
Location: Humboldt County, California
Posts: 78
Quote:
Originally Posted by Electronic M View Post
B+ can safely vary by 30 percent in most tube TVs.

Your h out grid being positive instead of negative is very bad, and usually means your oscillator is dead or not feeding the grid. If the h out screen is high it usually means the plate is drawing far too much current.... this makes sense since if your grid is not negative enough plate current will be high(and positive grid will red plate the hot).

What I'd do in your shoes is disconnect the plate and screen of the h output and work on the osc until the output grid goes negative. The grid gets negative by rectifying the drive signal from the osc...if you unplug the grid or cathode of the output a negative voltage will not develop at the grid.

Not sure I follow all the way. Disconnect the supressor grid and leave the grid thats supposed to be negative connected?

Also the b+ voltages are way off. Like for B+ 5 is supposed to be like 125v and its almost twice that. Its supposed to drop down ex 420 to 400 to 375 to 350 to 275 so on.
Reply With Quote