Testing a CTC-11 horizontal hold control

[DavGoodlin]

Originally Posted by Kamakiri

This set originally came from Dave A. Here's a shot of it when I first picked it up at Dave Goodling's in Lancaster PA back on Feb 20 last year.....

Great job Tim. I agree that coil issue was perplexing, since shorting that coil is S.O.P. on CTC12 and later chassis to center the hold control range. Not so on the CTC11, this coil is center-tapped - an auto-transformer to feedback from plate to the osc grid, so you don't short it because of how critical this loop is. The adjustment is in the Sams 550-2, page 16 and requires a scope to match amplitude of the two peaks.

I would not mind putting that coil on two of my ring-testers to see if that fails the coil against a good one from my working '11, the resistance measurements sure didnt

Is that CRT a 21FJP22, or has it a formed safety glass for the 21FBP22? I covered it up and did not peek so I wasn't tempted to keep it