@Norton posted:I assume the smoke unit is driven off the R2LC, not track power. I didn't see a regulator on the board but if there is one the cap would only need to be around 6.3v.
Pete, the R2LC smoke output puts out half-wave track power in command mode and full-wave track power in conventional mode. Since there is a diode, it would all end up being half-wave. Half-wave 18VAC peaks at 12.7 volts, so the cap will charge up to the peaks. As I said, the Lionel smoke unit with the same arrangement has a 35V cap. The cap comes BEFORE the regulator, so it sees the full voltage. There is a regulator, it's missing as well.
I've never seen any of these smoke units run the fan on unregulated power, that arrangement would put 11-12 VDC on the motor, that would make quick work of that motor! I think we need to see better pictures. If they are feeding this with some other source of power, I can't imagine what the diode and cap are doing there. Here's a view of the bottom of a K-Line smoke unit, note the regulator.
