germanium transistor help

kristopher

Well-known member
Hello all, Long time reader, first time poster...
After years of building BYOC, GGG, and GuitarPCB, I've ordered 16 boards from PedalPCB. And I'm super excited. Should be a fun year of building.
I've ordered almost all the parts. I can't seem to track down: 1 pnp ge oc71 (Hfe 70-120) for the Simulcast, and 1 npn ge 2n1304 for the Repro Fuzz.
Small Bear was my previous source, but they're closed. Or rather, Hibernating. Perhaps I can wait for them to re-open?!?
I'm about to put my last order in from Mouser, and I get lost looking for replacements/substitutes/equivalents on their site. Any suggestions would be wonderful.
Thanks in advance,
Kristopher
 
At this point your best bet, at least in the US, is pedalhacker or stomp box parts. I saw SBP posted some Soviet ge transistors this week.

The other option is to order on ebay from reputable sellers and test those when they arrive. I'm waiting for about 200 transistors from Russia and Ukraine. I bought a DCA 55 too, which Newark had for $59 or so.
 
At this point your best bet, at least in the US, is pedalhacker or stomp box parts. I saw SBP posted some Soviet ge transistors this week.

The other option is to order on ebay from reputable sellers and test those when they arrive. I'm waiting for about 200 transistors from Russia and Ukraine. I bought a DCA 55 too, which Newark had for $59 or so.
As I recall (I might be mistaken), The 55 does not report Ge leakage.
1 pnp ge oc71 (Hfe 70-120) for the Simulcast,
I can help with that gain bucket but it might not be the same part #.
 
As I recall (I might be mistaken), The 55 does not report Ge leakage.

I can help with that gain bucket but it might not be the same part #.
It does report leakage on Ge, assuming it's accurate. See here: Info on DCA55 Leakage

I already tested the twenty or so Ge I bought last year from Small Bear. Weirdly enough my Hfe calculations using the Keen method on a Vero board were within the margin of error but my leakage calculations were double what the DCA55 measures.
 
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It does report leakage on Ge, assuming it's accurate. See here: Info on DCA55 Leakage

I already tested the twenty or so Ge I bought last year from Small Bear. Weirdly enough my Hfe calculations using the Keen method on a Vero board were within the margin of error but my leakage calculations were double what the DCA55 measures.
Groovy! I had one, but must have remembered that bit incorrectly. Thanks for the correction. (y)
 
The same part number shouldn't matter, as long as the Hfe is within the same range, correct?
And how can you help? By mail ? I did forget to mention that I am in Canada. If there are any Canucks listening, maybe they know a guy in Southern Ontario...
I am calling the "local" brick and mortar places.
 
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The same part number shouldn't matter, as long as the Hfe is within the same range, correct?
And how can you help? By mail ? I did forget to mention that I am in Canada. If there are any Canucks listening, maybe they know a guy in Southern Ontario...
I am calling the "local" brick and mortar places.
Right. What really matters (for pedal building) is;
The type - PNP/NPN which is referencing the polarity. NPNs require a positive power supply, while PNPs use negative.
The level of gain the device produces. (shown as hfe)
The current leakage of the device. (often shown as Iceo). Lots of discussion around this one, but it represents current that slips through the insulator and though a few circuits are designed with leakage in mind, most often you simply want as little as possible.
If the search comes up empty, I've sent doodads to Canada before....
 
Once I get my batch of transistors from Ukraine (terrible timing and circumstances), I'd be happy to send some necessary parts your way as well. I've got about 70 NPN coming from Russia that I should have next week and another 150 or so PNP from Ukraine, which hopefully I'll have sometime in March.

I've got some other PNP I picked up from Small Bear last year that work for the Duocast as well.
 
Wonderful. Thank you both for the offer and assistance. I will reach out again once I hear back from a few stores.

My amp builder friend says he may have a few in a drawer. Could be promising. I'd better look into how to measure them.
 
A quick Thank You again to Fig and gheorge77 for the offers. I was able to find a supplier in Quebec that has Germanium transistors in stock. I ordered a dozen different PNP's and NPN's for a few builds. So far so good.
They also have vintage NOS Caps and resistors and the like.
Checkout thedhtsstore.com
 
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