Hello, My 500B uses a 120 V single speed fan, but with a resistor in one leg of the AC feed. You can use a standard fan with this arrangement and get two speeds by putting a switch across the resistor. The resistor on my schematic is R4 250 ohm @ 10 watts. You are going to have a hard time finding a two speed fan either surplus or off the shelf @ a supplier as they were not commonly used.
Question. Do you have a scanner and if so would you please scan the schematic and parts list of your 500C?
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