Germanium Diodes for sale?

BuddytheReow

Breadboard Baker
Anyone got a handful of good germanium diodes they’re willing to part with at a reasonable price? Frankly, I don’t trust eBay for things like this.
 

peccary

Well-known member
Check out Pedal Hacker. Dude has lots of GE diodes and they are a trustworthy site.

 

Chuck D. Bones

Well-known member
I just got some of the 1N100 Ge diodes from Small Bear - do you guys think they'll be good in the Parentheses?
Try whatever you like for all of the diodes (stick with 1N5817 for D100). I would use schottky, like BAT41, BAT42, BAT46 or 1N5817 for D1 & D2. You don't need Ge there. Install D1 & D2 in accordance with V2. Use Ge for D8 & D9 for the authentic sound. Most people socket the Ge diodes. Read the Build Docs carefully, then read them again. Pay close attention to the notes at the bottom of page 2.
 

BuddytheReow

Breadboard Baker
And rightly so. The other guys gave you some good leads. Buy at least 10 (maybe more like 50), make the shipping cost worthwhile.
@Chuck D. Bones , can you offer your opinion on what type of diodes I should get? I understand it's a matter of preference on how it sounds based on the individual circuit, but im not an audiophile. For example, I can't really tell the difference in a rat circuit the difference in sound between a lm308 and OP07. In the silicon diode world the "standard" that I have seen for signal clipping is 1n4148, 1n914, etc. Can you suggest a "standard" equivalent in the germanium world?
 

Chuck D. Bones

Well-known member
In my mind, there isn't a "standard" Germanium diode. You'll see 1N34A in a lot of designs because back in the day, that was the most common Ge diode. Back then, 1N34A's were made by just about everyone in the semiconductor business. The was a lot of variation in those parts, so buying a 1N34A, then or now, doesn't guarantee a certain sound. The good news is that in most pedal circuits, the Ge diode part number is not all that important. The Russian D9x diodes are popular and plentiful. I've used different ones and they all sound good to me, for whatever that's worth. Small Bear has 1N128 (Raytheon and the blue ones), I've used the blue ones and they sound good. At some point, it comes down to cork sniffing. My advice is buy some that are not too expensive, install them and enjoy your pedal.

I expect most builders on these forums have their favorites and will chime in.
 

Chuck D. Bones

Well-known member
One more thing about Ge diodes: like Ge transistors, they can be very leaky. Doesn't matter much in circuits that use them as hard clippers, like the Distortion+. It's critical in circuits like the Cornish G2 that use them as soft clippers. Leaky diodes kill the gain in that circuit. Ge leakage is a crap shoot. If you're building a G2, or something like it, best bet is to obtain some different part numbers, test them and hope for the best. "Hope" is not the best strategy in engineering, but sometimes it's all we have.
 

jubal81

Well-known member
One more thing about Ge diodes: like Ge transistors, they can be very leaky. Doesn't matter much in circuits that use them as hard clippers, like the Distortion+. It's critical in circuits like the Cornish G2 that use them as soft clippers. Leaky diodes kill the gain in that circuit. Ge leakage is a crap shoot. If you're building a G2, or something like it, best bet is to obtain some different part numbers, test them and hope for the best. "Hope" is not the best strategy in engineering, but sometimes it's all we have.
This exactly.
I've gone 15 rounds with Ge diodes more than a few times and for me, the leakage is the only factor that matters. I check the reverse resistance on them with a DMM.

I haven't found a Russian Ge diode yet that wasn't extremely leaky (less than 500K on my Fluke and sometimes a LOT less).
Other types (including 1N34s) can vary wildly from one diode to the next. I sort the ones over 1M into the 'less leaky' pile.

The only part number I've seen that's consistently not leaky is 1N695. I've never found one below 4M or so. They're typically about 6M. If you can find the black or solid blue ones, all the ones like that I've tested have been over 6M reverse resistance on my DMM. So if you're trying to build a G2, I'd recommend adding the 1N695s to your shopping list to try.
 

BurntFingers

Well-known member
Well, I just had 30 ebay '1n34a' diodes arrive.

The vf is around .35v on all of them according to my DMM. They're smaller than the tayda ones, looking more like 4148s or something. But, they clip and they do the diode thing so that's fine by me.
 
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