Recommend some NPN Ge transistors

[Chuck D. Bones]

That's just a general range, but different circuits will play better/sound different with different values, and the Fuzz Face is fine with higher leakage transistors.

The FF will tolerate a leakage up to a point. Too much leakage in Q1 will screw up the bias point. Germanium transistors should be auditioned in every circuit because: a) it can be difficult to predict how they will behave many circuits; b) what sounds "good" is very subjective.

 

[DAJE]

Got my bag of Soviet-era MP38As today. Did a quick test and all but one are between 60-110 hFE. The outlier tested at 40, but that's still potentially useful. They seem slightly leakier than your usual USSR trannies, which is also cool.

The other numbers have to be month/year, which means they're all from the mid 70s, coming up on 50 years old. Genuine vintage.

 

[Chuck D. Bones]

Watcha gonna build? Not too late to enter something in the Muffin contest.

 

[DAJE]

Watcha gonna build? Not too late to enter something in the Muffin contest.

AFT Preamp AKA EQD Bows AKA a Rangemaster with NPN tranny. I have a PNP Rangemaster I built a while ago but the simplicity of the Aft is attractive. I grabbed a few of the simplest PCBs last time I shopped from here. I only need one transistor for that so I'm pretty sure to be looking out for uses for the rest of them.

I'm still at the learning-what-the-things-do phase, designing something myself is a bit too advanced for me. Great concept, though, I've been observing the Muffin contest progress.

 

[Chuck D. Bones]

Don't be surprised if the AFT / Bows bias drifts all over the place. R5 is way too small, should be at least 1K. It's 3.9K to 4.7K on the Rangemaster.

 

[DAJE]

Don't be surprised if the AFT / Bows bias drifts all over the place. R5 is way too small, should be at least 1K. It's 3.9K to 4.7K on the Rangemaster.

I socketed the bias resistor on the Aion one I built last year, and I'm glad I did because I had to try a series of them to get it to bias. Thanks for the tip, I'll socket that one too. I've used a few of your tips in builds already, and haven't regretted it.

 

[Chuck D. Bones]

If it was my build, I'd install 2.2K for R5 and tweak R4 to get Q1-C around 5V to 5.5V. The bias will be stable and you'll have plenty of headroom.

 

[DAJE]

If it was my build, I'd install 2.2K for R5 and tweak R4 to get Q1-C around 5V to 5.5V. The bias will be stable and you'll have plenty of headroom.

Noted. I have another couple of pedals in the queue before the Aft, but I will save your advice and apply it. Thank you.