Great Jumpin Germaniums! (Ge Diode and Transistor Reviews & Discussion)

[Beaker]

Good haul Silver. Intrigued by your mystery fuzz - keep us posted. I guess I need to get some 308s ordered in ready to go.

Can I get I get a job on the GE Death Star - I can make tea?

[rocket88]

Well since I got put in charge of it, I say of course!!! Not even sure why you'ld feel you need to even ask. I'm sure you can do more then make tea. Besides, I thought you should be kept away from fire?

Plus, your a brother from the other side of the ocean. There's only like 2 people that I would say would not be in, mostly because there's no way that I could spend time stuck in space with them in the confines of the deathstar.

[Silver Blues]

Yeah it should be interesting. Going to see if I can get my theoretical circuit on the breadboard soon.

I tested all the transistors too, and I'm happy to report that all the 308s have a gain range of 300-450 and leakage under 20uA. I actually wasn't expecting so much gain out of these (I feel like I did something wrong... I half-assed the gain math though so that might be it). Of all the ones I received I think my highest leakage was like 25uA. The BCE pinout is a little weird though.

[rocket88]

Holy hell!!!! The 1t308's had gains ranging from 300-450? That's insane. Non of mine were anywhere near that high. I can only imagine what you're going to so with them now....

[Silver Blues]

Yup that's what my tester said  I had no idea, this thing is going to be nuts. I may have to dial it back

[Beaker]

Silver, don't forget these things are very temperature sensitive, I soon learned from my MP38s that I could quickly double the HFE reading by holding them in my hand for a minute.

I've just placed an order for some GTs so happy days!


And yes Zach, I should probably kept away from fire and sharp pointy things.

[Silver Blues]

Right, thanks. I don't really remember how long I held them before testing them. I can't imagine it's long but you never know. Either way they're pretty good spec, now it's just to see how they sound!

Also now that I mention it, I should probably ask for some tips on getting accurate readings. What I did was grab a transistor, slip a piece of wire insulation over the collector, gently twist the legs, place it in my tester and let it go. (Now that I recall I may have held a few down with my thumb which is probably not good.) I'm guessing I should handle by the leads not the body?

[Travis]

If they're going from ~100 to ~350 with a few seconds of handling then they are too unstable to use IMO

More likely that you have a batch of high hfe trannies or your readings are incorrect

[Silver Blues]

I'm thinking they're just high (which is great). I got a few others with the order that sat right around 125. I think the battery in my tester might be dying, I'll replace it later and try again.

I should note that the readings didn't fluctuate much at all, even with the ones I held down, so I don't think stability is going to be a problem.

[dbat69]

Silver, are you using an Atlas DCA tester? or just a normal one and plugging them into the hfe socket?
If it is the latter, you will get a higher value as a normal multimeter does not test Ge transistors correctly.  If you are using a DCA - you lucky boy

[Silver Blues]

Lol neither. I built the germanium tester from this site. The leakages are really low on all of them so the gains end up only slightly lower than the reading on my voltmeter.

[rocket88]

My thought is that from putting them into the tester your hand is heating them up and not letting them cool to room temp. But, then again I could be completely wrong. I'm just in charge of the Ge deathstar.

Now that I think about it, does that make me darth vader or the emperor?

[Silver Blues]

My thoughts as well. I've just finished swapping the battery, and I stuck one in the tester and am going to leave it until after dinner. Let's see what happens.

I think that makes you the emperor

EDIT the one I let sit reads a leakage of 19uA and a gain of 54.

I was doing my math wrong (multiplying by 1000 instead of 100). Fuck me... but I've got it now. This seems so much more reasonable.

[Travis]

Glad you got that sorted out! This is why DCA55 battle testers are standard issue on the deathstar. The only thing you need to worry about then is the dreaded "bicolor LED" reading

[rocket88]

Got to agree about the DCA55. I can grab each leg of the transistor without even touching it. Bye, there are some Ge transistors I've got that have gains over 100 and leakage, up to about 700!!! They're the tiny one, I think gt109 without going to actually check. The only thing is they're not as warm sounding as the other Ge's we use. They're almost like a cross between Si and Ge.

[strassercaster]

i just scored some 2n1302  texas instruments npn ge. man they are great almost sero leakage all between 70-110 hfe i bought twenty on ebay not a bad one in the bunch. most between 84-101 . they sound great

[Travis]

I've got a small stash of those too (maybe 30 or a little more) and they're excellent. Wish I could find them cheaper though

I finally got a new battery for my DCA55 so I tested a few things I got way too long ago.

2SB345 - holy shit. Some of these are super leaky! I found one with hfe around 80 and leakage around 500ma. Sure enough, I started playing around with them in my FZ-673 build and love em. They're real leaky though..

1T308B - well the B is what's printed on there but I dunno the Russian alphabet so I dunno if that's the same B as english. Hfes all hover around 70-80. BCE pinout. I hear these are just great in a fuzz face anyway so I'll try that out. Gonna need to build the bonermassa. Leakage is reading 0 for all of them

That's all for tonight anyway. I got distracted by the blistering awesomeness of my FZ-673 build. Yowza

[rocket88]

russian B is english V

[KT]

Hi Travis,

On ebay I only found really expensive 2SB345s. Where did you get them. I have been looking for super leaky germs for MkI type builds.

Thanks

[Travis]

The eternal question. I got them on eBay of course. I only have 6 left so I need to find more as well.

I know smallbear added lots of Japanese stuff a few months back. Worth checking in over there. It won't be cheap but a lot cheaper than the one dude on eBay right now..


Zach - thanks. I thought I remembered that but wasn't sure :)