I'm restoring a 1976 Mercury 204 "Drugstore" tube tester. I have a schematic which may be from an earlier model and shows a diode in the circuit where I found this component If this is a diode, I've never seen one like this. Does anyone have any ideas? It tested 1.8M ohm in one direction and 900K ohm in the other direction.
Thanks for any help.
Jim
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I think it could be a selenium rectifier (yes a diode of a sort).
Plus sign usually denotes the positive out, not the P junction side as in diodes (which would be the negative out).
whats other side of disc look
Since it comes apart, I believe it is a button cell battery assembly. Are there any bias voltage symbols in that part of the schematic? Some of the old bias cell symbols look like a modern diode symbol except it should have a + and - on either end.
that's what I was thinking tab but didn`t what to be ridiculed for saying it looked like a battery in tube radio
I was shocked to find one in a 37-602 philco. I didn't even know they made batteries that small in 1937 let alone use them in a tube type electronics. Although it looks different than modern button cells (acorn shaped) it is about the same diameter as a watch batt.
I've found out that it's a copper oxide rectifier and that they rarely go bad, so I'll put it back together carefully and reinstall.
Thanks for the suggestions.
Jim
Never heard of those before, learn something new every day. Since they "rarely go bad" it's strange that it would be in an easy access/replaceable assembly.
The copper oxide alloy is not solderable, hence the spring/clip type connections. Be sure you put the "disc" back in the way it came out
so it matches the polarity marking. ;)
Chuck