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Blue balance pot (trimmer on the PCB, not the drive or screen pot) is bad.
This is a 2k pot. I will work on getting it out later, and then just tack in a couple 1k for a fixed voltage divider until I can find the correct replacement.
The problem shows up as no blue in the color programming regardless of screen or drive settings. My guess is the imbalance in the circuit is just cutting off the blue gun completely. If it rock the tuner off channel to get a blank raster I can adj the drives as expected for a grey screen, but as soon as I try a signal all I get is red and green, and even then the green is not quite "right" I presume due the the absence of the correct blue color difference amp cathode bias signal used to matrix out the green.
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