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A higher wattage rating won't reduce the heat.I left the PCB running for hours in attract mode last night & the house didn't burn down so I presumed everything past C35 wasn't doing any harm. Cleaned the legs on the original resistor and reinstalled. Installed one of these in place of the LM323 regulator as I had it on hand. PCB now works on power from the original power supply. Voltage is 10.03 at the edge connector, 5.19 following the space-heater resistor, and 5.16 at the far end of the board.
I'm assuming the gunk on the original resistor was preventing power flow from my DC power supply from getting into the board, accounting for the voltage drop I was measuring, and that he LM323 was bad or shorted somehow, causing issues when feeding it with the OEM power supply. Will leave it running and wire up controllers to test out sound and gameplay.
The wire wound resistor put off a lot of smoke, presumably burning off dust I hadn't completely cleared out of it. Its still pretty hot. Any value in replacing with a newer resistor type with a higher wattage rating?
The heat is given off by the resistor, which is acting as a voltage divider in a network.
P (power dissipated) = V^2 (voltage squared) ÷ R (resistance)
Measure your voltage drop across the resistor, and plug in the formula. You'll see changing the rating higher won't affect the power - the key factors are resistance and voltage drop.
Or if you know the current through the resistor, you can use this formula:
P (power dissipated) = I^2 (current) × R (resistance)


























