After a moderately lucky bid on an auction, we've got our hands on a flight-cased 501 with no power supply.
We paid very little and want to get it running and hopefully install in our studio (we have a Scorpion ii currently).
Blue Dog power supplies in the UK will happily make us one but they don't know the PIN OUT on the power inputs, so can't make us up the missing cable, which we can't even find out what specific connector would be needed.
I also had a couple of other questions for any 501 owners - ours has two power inputs, one that someone has sharpie'd "red" - does the 501 require two PSUs or is it for a redundant PSU? I've attached a pic.
Any help to bring this desk back to life would be super appreciated!

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