I may be in the market to buy some diodes soon. I’ve heard so much negativity about buying diodes on EBay. I just wonder if there is any way to tell if they are going to be fake or real before purchasing. I see posts like this (see attached screenshot) all the time and they look good in the pictures. I assume 90% of the time these types of posts are bait for buying fakes, but it would be case-by-case. Anyway, if not EBay, what is a good reliable source for buying quality germanium diodes in bulk, or is that just it (there isn’t one, it’s an ongoing search)?
The seller in your screenshot, Sovcom/Alexer1/Oleg is a very reliable source; you're not getting fakes if you buy from him. I've bought a lot of parts from him and they are always exactly as advertised. As a general rule, if you're buying NOS Soviet germanium diodes, then you're probably not going to run into issues with fake diodes. You start running into issues with fake diodes if you are looking for US germanium diodes like 1N34A. That said, it's very easy to spot the fakes. Real germanium diodes look like this:
Note how there is a thin wire touching a flat metal surface. If your diodes look like this, they're germanium. (There are some germanium diodes in opaque packages, like OA7, but they're a rarity and don't look like the modern silicon Schottky diodes that some sellers mislabel as germanium.)
Fake germanium diodes are usually silicon Schottky diodes, which look like this:
As you can see, they completely different. That said, if you're using germanium diodes as hard clipping diodes (Klon Centaur, Univox Super Fuzz, MXR Distortion+), silicon Schottky diodes are great substitutes. I actually prefer Schottky diodes over germanium diodes in most hard clipping applications. But they are not good substitutes for circuits like the Tone Bender Mk. III, where the germanium diode's leakage is essential for biasing one of the transistors.
SOVCOM is the go-to, no worries there, and ml-electronics/bg2014manue (two storefronts run by the same guy) are also reliable sources for NOS Soviet stuff. As mentioned there are a handful of good sellers for this sort of product in Ukraine and elsewhere in Eastern Europe, I wouldn't be too skeptical (but feel free to check in if you have doubts, a lot of us have loads of experience with this process).
I'm nervous about this as I have a few pieces coming in from around the globe. This far PtoP sales haven't gotten flagged for me though. UK, Taiwan and Poland have all cleared in the last month.
