Ok this thread is getting me super curious so here is what I have figured out. Again I'm not an expert here so please chime in.
- The four prong plug has a ground, a common neutral and two hots
- With no load I get 120 VAC on both hots from the power supply socket and also this is what I read in the bulb socket
- With the fan and light running I read 120 VAC on the fan and 60 VAC on the lamp
- There is no transformer (that I can see) in the unit so they must be reducing voltage using resistors or diodes there are about a half dozen each of those.
- There are two large doughnut resistors labeled 50K719M I wonder if those are being used to halve the voltage? If so then why are they running an 82V lamp at 60V, my understanding is that you don't want to do this it is bad for the bulb. More likely explanation is I don't understand this correctly.
- There is also a relay switch, a few transistors and capacitors on the board.
- Everything fits onto a 2.5 x 3 inch PCB so there isn't a huge amount of parts or complexity
- This seems like the kind of thing you could get made relatively easily and cheaply in this day and age.
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