Search results

Here's the results for the box of 100 1T313V, though there were 4 or 5, 1T313B sprinkled in. The data sheet suggested a hFE range of 20 - 250 so I had high hopes there would be a nice range of gains in the box. However, as you will see from the results, that was not the case. In fact I would say...

Bought a box of 50 П416Б Russian NOS Germanium Transistors from eBay. Spent the day in between working chucking them in the TC1 tester, so take the results with a grain of salt I guess. Apparently these are known for being low leakage, in fact the TC1 did not report an Iceo for most of them...

Would it be super gated essentially?

For more context, all of the Russian ones I've tested so far have been ND on the Iceo and I know they have a reputation for very low leakage.

I guess it would be nice if the NPNs were low leakage cause NPN germs are so rare. Guess I'll have to construct the RG Keen tester after all.

These are the results of my tests so far. All done on the TC1 edit: updated table ND means not detected / reported. Unfortunately I have no way to know if ND means the leakage is too low to detect or is crazy high.

Hmm so I've been testing the NPN versions the 3BX31C, and the TC1 doesn't detect the Iceo leakage on them, I'm not sure if that means the leakage is just very low, or if because it's NPN it doesn't think they are Germanium? Anyone got experience testing NPN Germs with a TC1?

Question for you. When might I want leakier transistors? Just took receipt of this haul and will test them before buying other Germs, but I guess might look into a small batch of GT402s. I'm mostly interested in preamp designs for both guitar, microphone, and live level. But everyone should...

Update, here's a re-test with the TC1. This actually seems useful? Having said that, they've just been sat at room temperature. Do they need to be used actively to stabilise?

This is the cheapest quality one I could find. https://nz.rs-online.com/web/p/rackmount-cases/8104264 No Tayda level stuff for rack enclosures it seems.

Thanks so much for this and going to all the effort of creating the sims. Will definitely tinker with some of this!

For what it's worth a Bc549C BS170

Yeah, I'll reserve full judgement on the capabilities of the transistor testing until I have more high quality Germaniums on hand.

I think the issue is actually oxidation, which is caused by moisture, but can't be reversed by removing the moisture.

What's the TlDr, did dehydrating actually improve the specs at all? Seriously though, has anyone ever tried coupling Ge transistors to a heatsink similar to a MOSFET?

TLDR: AVOID. Hey folks, so given that I'm sure these FNIRSI devices have popped up on people's radars I thought I would share my experience with the DSO-TC4, a combination signal generator, oscilloscope, transistor tester. I purchased this device primarily for the SigGen and Oscope abilities...

I think there is a certain application where this is a desirable outcome, not in the "amp simulator" aspect perhaps, but I'm thinking as part of a boost circuit you may want a bit of extra compression without too much harmonic content.

Definitely interested in the home brewed stuff. I'm more interested in the "compression" effect of the cathode follower. With or without bootstrapping. I've been playing my Victory Cooper preamp over the weekend, and IMO the vox circuit does that compression thing really nicely, even when clean.

Almost any BAT diode will do the job. The BAT56 is a bit lower than the other common ones.

Going back to the original cathode follower concept, do you have any starting point schematics I could look at? Either at 18 or 24v? Would going LND150 into a JFET be a good idea if it's all about current flowing into the "grid"? Or maybe the other way round?