? Encoders

Hi List

I was digging through one of my treasure boxes last night and found what I
think are encoders.
They are about 1.5" diameter, .750 high, have a flat 10 wire lead with plug.
One of them was broken
so I opened it up. The lead is 10 wire but only 8 are used. The little
disk inside was broken, so
I removed it. It has a single line starting from the inside of the disk hub
and goes only about
.125 inches into the disk. Kind of like a timing mark. The disk has a
mirror like finish as does
the reader that is connected to the lead. The disk has a .250 center hole.
The case has two mounting
tabs. The markings on the case are BEI. The only numbers are stamped on
with white ink or paint.
I don't know if they are part # or what. They are 2 25, 012, 1024 and on
the back 8651.
Does anyone have a clue as to what these are. I sure don't, but then I know
little about electronics.
I have done several searches on line and cannot find anything except a lot
of other manufacturers of encoders. How would one go about testing these.
Thanks

Bruce

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