Quote:
Originally Posted by miniman82
I've never had this problem, so I'm struggling to understand what's happening. Perhaps some careful tweaking with the 3.58mhz trap would help? All you really need to do is sweep it, and make sure it's peaked correctly.
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It's hard to see; a 100-percent saturated solid color (I use red) test signal is needed that begins at the far left of the screen. Similar hue distortions have been witnessed occasionally with 'regular' video programming, where rotating the horizontal hold control adds and removes hue distortion. For example, some years ago when the Sarnoff Library was still in existence and had a working CT-100, I and others observed the same effect. Can't yet be sure if the same process was at work there as is here.
I assume you are referring to the 3.58-MHz trap in the plate of the first video amp. The burst is taken from the plate (via the 3-pF cap) before that trap, and so the trap, if misadjusted, I don't believe would reduce the amount of chroma contamination in the burst processing circuitry. It might leak some chroma into the Y channel of the matrix.
Pete