Piggyback Si transistors to simulate Ger ???

Frequently asked question on transistors: types, substitutions, how to test, use and misuse them.
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Post by R.G. »

atreidesheir wrote:Could I get a similar effect with a 2n3440 low gain (@50hfe) silicon transistor with a 1n34a tied to the base and collector to simulate leakage?
Probably. I've tried it and this reintroduces the temperature drift to an otherwise-temperature-immune silicon device. I posted this in other fora at some point.

It doesn't do much except introduce leakage, but that's good for those pedals that are otherwise leakage-biased. It fakes yet one more characteristic.

For faking the noise that surface contamination gives, there are other tricks as well. :D

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Post by atreidesheir »

"Contemplate it - on the tree of woe." :Thulsa Doom

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Post by ltdf50 »


I've been meaning to build mictester's buzzaround-alike (https://www.freestompboxes.org/viewtopic ... ound+alike) for quite some time now, but sourcing the Ge-transistor somehow held me back (I don't like paying shipping costs for just a single part). The solution of piggybacking Si-transistors came to my mind, not sure if it was because D-Day mentioned he built his buzzaround-alike this way in mictester's thread, or because I stumbled upon the piggybacking thread separately... anyway, the Ge-transistor in the buzzaround-alike is supposed to be leaky, so I'm wondering if piggybacking the Si-transistors like this https://www.freestompboxes.org/viewtopic ... 60#p215212 is a drop-in replacement, or if any additional modifications are necessary.


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