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Along the way I discovered that the -30V supply to the drive board had more hum than when I checked it earlier unloaded. This put hum on just about every output of the drive board. Going back to the power supply board, making measurements, checking regulator specs and doing some calculations I realized that one on the regulators was voltage starved. One of the resistor values was shown wrong on the schematic and parts list! The 2.7K value shown on the schematic had been replaced with a 1.2K when I first got it and that value worked in the circuit. I put a 1.2K back in but this time I knew it should have been a higher wattage due to my calculations. Changing that resistor solved the driver output hum problems.
Next the 3.58MHz (color reference) and 30Hz (VCR servo) outputs, they used the same output module. When I opened the module cover I got a surprise! The small board was burnt in the center almost all the way through it. Three transistors were also toast. I never smelled anything burning so the damage was done before I got the VA62. Since I don't plan on working on VCRs and seldom work on color TVs, I decided to just disconnect the power to the module.
To be continued.
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