1966 Zenith 20X1C36 failed vertical output transformer

[Dave Drez]

One last comment on the Vertical sweep issues that I have been having with a 1966 Zenith... At the time I posted my comments about the "non-working" nature of the vertical linearity control, I didn't have a set of vertical oscillator and vertical output tubes
to swap. Since then, I ordered a pair and they arrived. I have found that this "newer" vertical output tube has made a tremendous improvement to the functionality of the vertical linearity and all of the adjustments. The geometry is now very good. The "older" tube was a 6HE5 and is now a fully compatible 6JB5. I changed the vertical oscillator tube - a 6BA11 and it didn't matter so much. I kept the 6JB5 in and the Zenith is much improved!

Dave

[JohnCT]

Originally Posted by Dave Drez

I have found that this "newer" vertical output tube has made a tremendous improvement to the functionality of the vertical linearity and all of the adjustments. The geometry is now very good.

Glad you found it. I would have commented that while geometry adjustments were always a song and dance number on any vacuum tube TV, certain TVs of the era were far less finicky. Zeniths were among those that were fairly easy to setup, and under no circumstances should any of the controls in a Zenith be at their limit.

The only quirky thing with Zenith was the audio. I don't know the reason (patent avoidance?), but Zeniths often would buzz in the audio, and indeed had a "buzz" control (potentiometer) on the back apron. Other than that, any Zenith should have excellent geometry and excellent vert and horiz lock.

John