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Old 01-06-2016, 10:54 PM
old_coot88 old_coot88 is offline
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Join Date: Sep 2009
Posts: 2,647
Quote:
Originally Posted by wa2ise View Post
Video signals have a polarity, and you can have it be upsidedown. Not upsidedown as if the vertical yoke were wired backwards, but the video looking like an old fashioned photographic negative. Whites being black, blacks being white, and so on. Also the sync circuits won't sync up.
(For any noobs' benefit), phase inversion occurs because a tube's plate is 180 degrees out of phase with the grid. I.e., grid goes positive, tube conducts more, plate voltage drops. Then grid goes negative, tube conducts less, plate voltage rises.
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