Try your local Maplins
It presumably would only matter if the lamps were LEDs and I can't think of any likely situation in which it would do any harm to get the polarity wrong with LEDs (they just wouldn't work) - so it might just come down to trial and error.As suggested buy a 24 volt DC power module and change the plug on the lights to suit it. Not sure how to determine the polarity. Is the flat pin the Positive or the Negative pin. ?
Since when did speakers know anything about + and - ?I thought the round pin was + on speakers
I imagine that there was/is - but I don't think one could readily translate that convention into "+" and "-" when being used for a DC power supply!It's a good idea to have them the same way round, so maybe there was (is? - does anybody use those awful things for speakers any more?) a convention for wiring them.
Another quiet day, I see<a picture of speaker terminals labelled "+" and "-">]
As I said, I really don't think it would be the end of the world if one got it wrong first time, so I personally would be happy with trial and error, maybe starting with an educated guess!It would be nice to start with an educated guess ... And get it right first time.
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