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

[bogey]

Ha Ha , I thought there might be a "but".

Thanks Beaker, good to know.

BTW do the same hfe gain values generally apply to silicon trannies?

[Beaker]

No. Silicon go way higher. low gain silicons start where Ge's end around 200hfe. High gain ones (NPN Darlingtons)are ten times that.

[Kinski]

Anyone have experience with any German made GE transistors? Hfe? I'm especially interested in leakage. As all I have are no leak Russians at the moment. And I've seen some German ones recently.

[rocket88]

I haven't seen the German ones. What model numbers and manufactures? I'll do some research.

[Marbles]

I don't know if this belongs here, but I think the high Hfe transistors from the Elena seller on Ebay have been dried up, or reserved for others, but I'm not getting any anymore, so just a word of advice.

The gt308v advertised as Hfe from 80 to 200 have all been in the 60-70 range so far (bought 150, have only tested 30 so far, but none above 80).

Also bought mp38As, same thing, from the 30 I bought, 4 of them above 80, 5 above 70, the rest around 60 and some even below. Now those are advertised to be between 45 and 180, so that's a risk I took myself.

[Pavlos]

I'm just starting to dip my toe in the waters of the Germanium sea so with some guidance from Zach, Travis and Beaker (Much apperciated guys) I orderd quantity 10 AC125 from Orpheus on November 15th and thety arrive yesterday (Economy shipping to UK)and tested out as follows

HFE Leakage
83 0.12mA
92 0.1mA
95 0.12mA
95 0.12mA
96 0.1mA
104 0.17mA
121 0.25mA
124 0.23mA
127 0.21mA
129 0.23mA

At the same time I also ordered these from our Bulgarian friend, and they arrived yesterday as well (Again, economy shipping to UK)

MP38 Qty38 orderd(Received 38)
MP20A Qty 20 ordered (Received 20)
MP21A Qty 21 ordered (Received 23!)
D9B Qty 100 ordered (Received unopened sealed box of 100 date stamped APR 1980)
D18 Qty 100 ordered (Received unopened sealed box of 100 date stamped 29 ИЮН 1982)
D311 Qty 100 ordered (Received unopened sealed box of 100 date stamped 31 AVG 1973)

And they tested out as follows


MP38
HFE Leakage
39 0.04mA
42 0.04mA
43 0.06mA
44 0.04mA
45 0.04mA
47 0.08mA
47 0.1mA
48 0.04mA
48 0.06mA
48 0.06mA
48 0.06mA
48 0.06mA
49 0.04mA
49 0.06mA
49 0.06mA
51 0.04mA
51 0.06mA
51 0.06mA
51 0.06mA
51 0.06mA
51 0.1mA
52 0.06mA
52 0.06mA
52 0.06mA
53 0.06mA
53 0.06mA
53 0.08mA
54 0.06mA
54 0.06mA
54 0.08mA
54 0.08mA
54 0.08mA
55 0.04mA
55 0.04mA
55 0.06mA
55 0.06mA
55 0.06mA
57 0.06mA
60 0.06mA


MP20A
HFE Leakage
45 -
48 -
48 0.04mA
49 -
52 -
54 0.06mA
55 -
58 -
59 -
59 0.04mA
62 0.04mA
65 0.04mA
69 0.04mA
69 0.04mA
72 0.04mA
84 0.06mA
88 0.06mA
89 0.06mA
92 0.06mA
96 0.04mA


MP21A
HFE Leakage
49 -
50 -
55 -
55 -
55 -
56 -
56 0.04mA
57 -
58 0.04mA
60 -
61 -
62 -
62 -
62 0.04mA
62 0.04mA
63 0.04mA
64 -
65 0.04mA
65 0.04mA
66 0.04mA
68 -
72 -
80 0.08mA


Extras included were

SFT308
Germanium
PNP
HFE Leakage
58 -


GT2 307
Germanium
PNP
HFE Leakage
99 -


GT1 323
Germanium
PNP
HFE Leakage
123 -
123 -
129 -
134 -
213 -


GT1 353
Germanium
PNP
HFE Leakage
80 -
112 -


MP25
Germanium
PNP
HFE Leakage
40 0.06mA


MP26B
Germanium
PNP
HFE Leakage
31 -
35 0.06mA


AC125
Germanium
PNP
HFE Leakage
54 0.04mA
59 0.06mA
62 0.06mA
124 0.15mA
133 0.21mA
136 0.27mA
149 0.19mA


P403.1 72
Germanium
NPN
HFE Leakage
31 -


BC214KC
Silicon
PNP
HFE
287
291
317
345


MP101
Silicon
NPN
HFE
10
11
12
12


310 7B
Silicon
PNP
HFE
88
99
99
118


BC416
Silicon
NPN
HFE
272


BC415C
Silicon
NPN
HFE
390
445


BC414C
Silicon
NPN
HFE
374
393
506


BC413C
Silicon
NPN
HFE
487


PN 2N2222 (Metal can)
Silicon
NPN
HFE
191
222


KC509
Silicon
NPN
HFE
448
478
481
499
502
509
516
522
542
552
583
592
620
633
686


There were also a few other silicon transistors that have no markings on them (Various HFE) about 30 capacitors most of them being physically vey compact electrolytics, about 15-20 small blue beads with coloured dots on them (Anyone have an idea on what they might be?) a couple of chunky metal cased diodes, 3 large bolt style diodes (Approx 14mm across) a few fuses, and 3 snapped pieces of pcb with god only knows what on them, grey metal casing, roughly running track shaped, approx 32mm long, 23mm wide, 16 mm high, two parallel rows of 4 pins out the bottom?

Looks like I might be able to keep myself gainfully occupied over the winte

[motterpaul]

You managed to acquire in one day what a lot of us do over a year or more. It's good to have variety and I am looking forward to seeing what the "germ" experts here advise you to do, especially since I have a lot of the same parts.

[Pavlos]

well I had a list of things I was interested in building if I was going to try my hand at Ge builds, pink/purple fuzz, EGDM, Crimson Drive, various Tonebender variations and derivitives and a few others, and after a fair amount of me blindly asking lots of questions, Zach, Travis and Beaker gave me a huge amount of help and some suggestions of what to get and quantities that would give me a decent chance of having enough 'good' transistors to have a realistic chance of at least few successful builds. So with a mixture of that advice and looking at cost vs quantity = value for money, it made more sense to go for 20 + of each (If I was looking to build for others it'd probably make sense to buy 50 to 100 + at a time) rather than multiple buys of smaller quantities. Especially true of the diodes, buying 10 or 20 at a time works out very expensive when you take into acount that they are often used 2 or more at a time, so it's pretty easy to go through 30 - 40 without even noticing, and those boxes of 100 were a no brainer at the price, should keep me going for quite a while 

overall cost wasn't exactly cheap, but then again Ge stuff never is, and it made more sense to buy in one hit and keep the shipping costs down, than bitting and bobbing. Total cost including shipping worked out at roughly £60GBP which considering how much I got isn't silly money, and does give me a reasonable stock to play with, and as you say it's definitely good to have variety. With the mix of different diodes and transistors I ordered, along with all the extra goodies, I reckon that gives me plenty of scope to experiment oh, and also save up for any future purchases of course!

[Beaker]

Marbles, those MP38s will be great - don't be dissapointed about the gain figures you have. All the ones I have are a similar gain, and I've yet to find a build where they don't sound good.

[Beaker]

Pavlos, that's a good haul you've got there - don't you just love those diode boxes? It's worth getting them just for the packaging, my Graphic Designer son-in-law is obsessed with the things.

That's quite a task testing that lot - I don't really bother testing until I'm ready to use them.

[Pavlos]

It is quite a haul isn't it, and it's at least partly your fault matepretty much all looks to be in a useable range of HFE, but I'm not too sure about the leakage on the AC125? hopefully I can get a bit of advice there though? and the extras, I was surprised by the sheer quantity to begin with and when I sorted through it, very pleasantly surprised Testing wasn't too much of a task really, I had the day off, the weather wasn't anything great and I wanted to see what I'd actually ended up with, so plenty of coffee and good music makes it a far less of a chore.

Those diode boxes are great, so stereotypically eastern bloc, the whole style screams soviet state sanctioned art! takes me back to being in the forces during the cold waroh how things change eh! just goes to show that people the world over have more in common with each other than the differences that divide us

[Beaker]

I'm not the guy to ask about those AC125, as I tend to steer clear of PNP builds. I've only built a few, and not done much in the way of trialling and testing those builds for different gains and leakages.

Zach, Travis and others know far than I do about this.

[Pavlos]

Thanks Beaker, not that you haven't already given me a lot of help and good advice on this already and that's what I like about you guys, you're always willing to help out, and however much you know (Which is hell of a lot) you're always quite happy to defer to someone with greater or more detailed knowledge on a given subject.

[Marbles]

Great to hear! I have only used 2 of them so far. One in a Skreddy Lunar module and one in a DAM Red Rooster.. Especially the latter sounds and feels great. I tried a bunch, but ended up with the highest hfe I think.

[Travis]

You have a lot of good readings from the AC125s for the MKIII Tone Bender you were wanting to build. I usually use hfe about 90 and up for Q3 and test them by ear.

If you find out what those blue blob things are let me know. Zach and I both have a pile of them that we don't know what to do with

[Pavlos]

Thanks for the confirmation about the AC125 leakage Travis looks like pretty much all the transistors I ordered are useable in some form or other which is a very pleasant surprise though to be fair I did get a lot of help and some good advice to work from  And I'm impressed with the extras as well, particularly the transistors, no idea what I'm going to use them in but it can't harm to have a bit of choice eh! The MP101 are the only ones I'm struggling to think of any use for though, HFE is only 10 - 12 so maybe in buffers?

Would I be correct in assuming the the leakage on the MP20As and MP21As would be useful in Q1 and Q2 for circuits that benifit from it? and also that the leakage on the MP38s isn't likely to be an issue?

As for those blue blobs, Silver Blues posted this http://guitar-fx-layouts.42897.x6.nabble.com/Great-Jumpin-Germaniums-Ge-Diode-and-Transistor-Reviews-Discussion-tp13256p18920.html thinking they might be bead inductors? top right of the second photo look just like what I have so who knows

[Travis]

The leakage of the MP38A, MP20A, and MP21A is low. You could use them for Q1 and Q2 in MKIII Tonebenders. You could also use the lower hfe AC125s for that. You could use them in most circuits. Fuzz Face, Tonebender MK1.5, MKII, Rangemaster etc.

Some of the lower hfe ones (30-40) can be used in the Carlsbro Fuzz, or Q2 of the Ge Fuzzrite or Orpheum Fuzz

[Pavlos]

Thanks Travis, from the help you'd already given and a bit of reading through various posts I thought that might be the case, always good to have it confirmed though and now the fun begins

[Silver Blues]

Yeah they're bead inductors  no real use for them in pedal circuits that I've seen, unless you happen to find some filter that calls for one of those values.

[rocket88]

damn. i've got a metric ton of them. i wonder if there's a way to string them together to get the inductance you want. side note, how can we figure out their inductance to even see if they're usable.