View Single Post
  #2  
Old 11-21-2016, 10:06 AM
old_tv_nut's Avatar
old_tv_nut old_tv_nut is offline
See yourself on Color TV!
 
Join Date: Jul 2004
Location: Rancho Sahuarita
Posts: 7,784
Quote:
Originally Posted by Kamakiri View Post
Have an issue with hot plating on the horizontal output tube of a CTC-11, and I'm pretty sure that I've traced it to a bad horizontal hold control.

This is described as a sine wave coil. I assume to test it properly the set has to be set up on a scope, but is there any way to test it for an open while out of circuit?
Not really familiar with the chassis, but looking at the SAMS, to ADJUST it properly requires a scope and adjusting the H osc simultaneously to keep sync.

Out of the circuit, you can check for open with an ohmmeter, but if the problem is a shorted turn instead, that would be hard to tell.

It looks to me like it's the only DC path to the H osc plate. If that is correct, and it's open, the H osc would die completely. Is that what you are seeing with hot-plating? It also means you could check for an open while in-circuit (with power off, of course [adding this comment in case someone less knowledgeable reads this in future]).
__________________
www.bretl.com
Old TV literature, New York World's Fair, and other miscellany

Last edited by old_tv_nut; 11-21-2016 at 10:12 AM.
Reply With Quote