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Old 10-13-2024, 09:29 PM
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Quote:
Originally Posted by loud41 View Post
I see. I've attached a small screenshot of the schematic showing the location of the video detector for any who might be interested.

Yeah that's kinda what I was thinking as I've been staring at the back of this unit. Unplug the motors, clean the pots and contacts, and not really mess with everything else unless I have to. I don't want to disturb more than I really should.
That detector puts out a 3V p-p video signal, with sync negative as shown in the schematic. It would be easy to build a video input amplifier with a gain of 3. However, the DC level is also negative, with whites at about -0.3 volts and sync tips at -3.3 volts. To duplicate this, you would need to add a negative supply, which the chassis most likely doesn't have, to reference DC restoration of the sync tips to minus 3.3 volts. Not impossible, but a bit of a bother.
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