Help identifying these germanium diodes

crowquill · Post by **crowquill** » 05 Mar 2025, 23:19

I have these diodes that I bought from small bear in 2011 and have been in my diode drawer for over 10 years. They lost their label and I don't know which diodes they are. I was able to dig up the email receipt and it just says "NOS germanium diodes"

Anyone have any idea what they are?

Post by **modman** » 06 Mar 2025, 01:23

Matsushita? OA7x series? Have a look here:
https://www.eonet.ne.jp/~k-matsu/germanium_diodes.html

mauman · Post by **mauman** » 06 Mar 2025, 05:31

I have some 1N34A with black-red stripes like this, but it's hard to know for sure. I think I'd measure the forward voltage, and the reverse capacitance if that matters to you, and just try them whenever you need a Ge diode.