I bought optos in bulk a couple years ago in case I had future problems with opto boards. I don't remember where from to look up the order, I don't have specs noted on the parts drawer. I used then today to try to rebuild my taf bookcase opto boards and they do not work.
I had a good look at them before installing, and am fairly certain they are oriented same as the originals. Is there a way to confirm polarity with multimeter?
Additionally, is there any way for me to figure out the specs with a multimeter? Or are these junk now?
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