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Old 11-04-2014, 08:05 PM
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Kamakiri Kamakiri is offline
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Join Date: Jun 2002
Location: Buffalo, New York
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Quote:
Originally Posted by old_coot88 View Post
The plate load resistor of the V.osc is a very common failure. It drifts high due to constant hammering by high level pulse.
Common problem not just in Zeniths but all designs using B Boost to feed V.osc.
B&W as well as color sets.
And drift high it did. Supposed to be 473K, tested at 567K. Picture is much improved, but still has foldover on the bottom. After about 5 minutes of folling around with the adjustments, the picture went somewhat out of focus, and I stopped there.

One interesting thing to note....every time the screen changed scenes drastically (dark to light), I'd lose vertical lock.
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