View Full Version : 1963 Zenith 19" b/w - vertical troubles


Adam
12-21-2012, 05:30 PM
I finally have some time in the next few weeks to fix some sets. First up was this Zenith, one I had working before, but now the vertical wouldn't lock in. The problem wasn't the oscillator running on the wrong frequency, but that the sync wouldn't stay locked in. So I figured the problem would be with the sync pulses getting to the vertical oscillator, and not in the oscillator circuit itself. The first thing I did was check the sync separator tube, which checked out ok. (Now referring to the attached schematic) I then checked the voltage at pin 8 of that tube which was low, then checked R58 which was about 1.2M instead of the 150K it was supposed to be. Changing that resistor fixed the problem. You can see my cat Fluffy checking out the picture on the newly repaired set below.

Adam
12-22-2012, 12:21 AM
Not about the Zenith - but this really didn't deserve a whole thread unto itself - I was working on my 7" Airline, reversed the wires to the horizontal plates in the crt when I was fixing a loose connection in the socket. :D Now I have to take it apart again and reverse it before I go to bed.

Adam
12-23-2012, 12:41 AM
Now that I got all these sets that I had working before, working again, tomorrow I'm starting on that CTC 9.

Glenz75
12-23-2012, 08:43 PM
Nice collection of sets you have there :yes: That Zenith is very clean on the inside and nicely laid out. Obviously a low hour set. Nice ;)
Cheers Glen

DavGoodlin
12-24-2012, 08:22 AM
Good find there! Those high-value resisitors seem to be problems in Zeniths.

If I had a nickle for everytime I suspected a sync sep or clipper tube.....