Help Understanding ACC

[TinCanAlley]

Okay, latest update.....

I decided to watch a few shows on the set last night and a couple of new issues came up that is pointing me towards the Chroma module.

Upon turn on the set, the tint was still not working as it should. The it was almost all the way counter clockwise in order to get decent skin tones. Anything more than a quarter turn and it went way into the green. Then after around 30 minutes the color flashed a couple times and it went B&W. I had to change channels and then back to get color again. This one is either the AFT or the Chroma module and possibly with the burst signal. A little while later, the color flashed again and this time it went full color saturation as if I turned up the color control to full. It stayed this way for about a minute or so, then went back down, but still higher than initially set.

So I know that the tone control is connected to the Subcarrier module and it manipulates the burst signal sent to the Chroma module. The color control is connected to the Chroma module directly. So if the tint setting is changing, and the color setting is changing, it seems the Chroma module is the culprit. The color disappearing might also be the fault of this module as well and changing channels resets the burst signal, or so I believe it does.

I will do what I can with the module as I can test all the caps, resistors and reseat the IC, but I don't know about the coils. Those coils are for Chroma Bandbass and Chroma Take-off. Not sure what those do and if it's even possible to test them in circuit or how to readjust one of them if I do something that changes its adjustment.

Might be time to look for a replacement module just in case.