I bought this kind of module for my led light project. Unfortunately it did not come with instructions.
It can be found from eBay with "3.5-28V to 1.25-26V DC-DC Converter Boost Buck Step Up Step Down Voltage Module"
My plan is to set a load on the "OUT" side, set up a multimeter and turn that screw in the down middle until I get the correct reading. Is that the way to fry the board?
Strange. This is a single supply module, yet it has two switchers on board.
Anyway. Yes, connect a voltage between 3.5V and 28V to the input and measure the output voltage, which you indeed should be able to adjust with the multiturn potmeter. Check the switchers' datasheets for the maximum output current. The right IC seems to be an LM25005, that can deliver 2.5A. May be a bit high for the coil though. The left one I can't read.