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Old 05-07-2026, 12:18 PM
ARC Tech-109 ARC Tech-109 is offline
Retired Batwings Tech
 
Join Date: Jun 2020
Location: Planet Earth
Posts: 599
That only handles the composite sync for the horizontal not video. In the bigger picture the buffer has been sidelined for the time in favor of the original IF strip as the op-amp itself doesn't have the swing the set needs on the 1st video amp. The issue with the IF strip turned out to be an open parasitic suppressor coil which was only letting a little signal thru on the internal 12K resistor and this was discovered using an IF sniffer connected to a later Panasonic TV.
As it turns out the 1st video is looking for a signal with 10 volts P-P to make the magic happen so an additional stage may be added at a later point, right now it's get a stable image on the screen and the chroma section working properly before I continue with the composite input.

Problem I'm having with the chroma has to do with this green shading that seems to be some sort of 3.50 osc leakage that's getting amplified by the XZ demod and equally imposed on the R-Y and B-Y. It goes away if I advance the color killer or pull the 6HS8 demod otherwise it's always present and baffling me. Just another bug to iron out.
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