RCA 21CT55 #8802897 is Dead

[old_tv_nut]

Originally Posted by miniman82

FYI, I did some research into black level resto on CTC based sets (I have a 9, a 7 and a 4). I ended up running into an old service document that said black level on those chassis was reset during every blanking period when the blanking tube went into effect. So in theory no resto should be needed, but perhaps the restoration effect of the blanker is not what it should be?

CTC-4 and later had only partial DC restore in the luma. All chassis had DC restore in the chroma, which is necesary to prevent the color tracking drifting in the opposite direction of the most prominent color in a scene.

In the CT-100, DC restore was done on the individual R,G, and B drives, so both luminance and chroma were DC restored.