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The other thing of course is, I'm not married to 9v. Using an external supply and an LT1054 means that anything up to 15v is possible, not sure how that affects things but maybe it will help these lower beta devices be more useful.

I think you would treat the composite like this, using the marked point as Bass, Collector, and Emitter for the test.

Yeah, I hate the idea of these devices just rotting away doing nothing. I know we have a tendency match a device to the circuit, and not the other way round, but that seems so wasteful? Surely there are some clever circuit designers around that can make these things useful.

Nice! I wonder if bootstrapping and/or negative feedback can help stabilise low Hfe Ge Transistor circuits. I'm curious eventually to make a cascading preamp design similar to the JFET amp simulators and see how it sounds.

How did vintage Fuzz Faces and Rangemasters handle this problem then? Given they would be connected to an amplifier down range? Once I built something permanent I will definitely use the charge pump inverter.

Nice, been interested in a Vari-Mu type thing.

Diezel and VHT sort of share a similar sound in my opinion, that dry percussive Marshall on 11 type of thing. I think the Valhalla is a good shout.

Ok, so I have decided to try my hand at the PNP Ge LPB-1 breadboarding. And wouldn't you know it, there's already a guide to do that (sort of) https://barbarach.com/npn-to-pnp-transistor/ I wanted to ask a clarifying question though, in this example below, this to me looks a lot like the...

Have yet to put any of these devices in a circuit. Funnily enough I'm not a big fuzz guy, I prefer the more "preamp" type stuff. I have so many on hand though I will likely give it a try.

Also very true, given how much signal amplification is happening before diode clipping, the softness or not probably has diminishing effects on the actual output.

Regarding the feedback, these Russian Germaniums have almost undetectable leakage so I'm guessing the negative feedback will be an important parameter.

Absolutely! I guess what I'm saying is, there seems to be some conventional wisdom that actually doesn't hold true according to some testing. For instance this statement: https://www.diystompboxes.com/smfforum/index.php?msg=1148986 I've heard many times that stacking diodes not only...

I actually do have a breadboard but I've never used it, but this whole endavour has deffinitely ignited my urge to learn. I've learned a lot since I first bought them so breadboarding seems a lot less intimidating now.

Let's say I made an LPB-1 but converted to PNP Germanium, and biased "optimally", would the only difference between say a 40 HFE transistor, an 80 HFE transistor be the total dB gain available, or would saturation characteristic be different too?

I've been reading up on diode softness and curve tracing and all that kind of stuff. 2 threads in particular have made me question some of our understanding of practicalities of measuring the softness of the clipping/conduction knee. Take this thread for instance on MOSFET clipping, in this...

I'm curious how low HFE affects the sound of the circuit, I've never actually built, or really even engaged with Germanium type circuits before, I fall on 2 extremes when it comes to circuits, subtle "sweetner" type effects, over drives used as boosts, and tight metal distortions. It seems...

They're PNP unfortunately.

If anyone has followed my recent NOS [PNP] Gemanium transistor box adventures you would know I now own a large number of ~40 hFE, low leakage Germaniums. These are obviously not at all suited for Fuzz circuits, but that's ok, I like more subtle pre-amp like effects a lot of the time anyway. My...

I tested one of the PNPs (3AX31C) that I had tested on the TCR-1. The TCR-1 tested a hFE of 64 and an Iceo of 66uA. My Keen tester (assuming it worked) read a voltage of 0.075v with 2M2 floating and 0.566v with 2M2 connected to ground which would equate to a hFE of 49.1 and a leakage of <50uA...

Ok so I made the RG Keen tester, I think based on the continuity test, when the switch is in the up position, the bottom two poles are connected? And in the down position, the top two poles are connected? I wired it so the 2m2 is connected to the top lug, and the middle lug is connected to the...