I have one of these old timers and the bar sweep and color sweep section is n't working. Strangely, there are color bars over the dot and cross hatch patterns which I don't recall being a normal situation. All the switches a re clean and tight.
Anyway, I have the full owner's manual that includes maintenance and calibr ation instructions, but no actual schematic.
Does anyone have a schematic of the 500 generator board and parts layout fo r the same board? This is the only board where the component legends are n ot silk screened on the board, and there are at least 12 ICs - all 16 pins each, most of them the same number.