help with fuzz and MP-41 transistor schematic wanted

[george79]

Hello,
i'm looking for a simple schematic for a fuzz with germanium MP-41.
Any help please?

Thanks
George

[tjdracz]

MP41 are just ordinary germanium transistors with quite a low leakage. Not sure about what hfe yours are but they should work with stuff like Fuzz Face for sure or you can try them with many other germanium fuzzes. Some like Marshall Supa Fuzz and such might need bit more leakage though

[george79]

i found those too,
i'm not familiar with the soviet transistors,are they better??

http://www.ebay.com/itm/50x-GT313V-80s-Soviet-Military-Grade-Germanium-Transistors-Ge-15V-30mA-100mW-/251488621989?pt=LH_DefaultDomain_0&hash=item3a8de3d5a5

http://www.ebay.com/itm/50x-GT320B-PNP-20V-150mA-200mW-Soviet-Military-Grade-Ge-Germanium-Transistors-/251517449437?pt=LH_DefaultDomain_0&hash=item3a8f9bb4dd

http://www.ebay.com/itm/Germanium-PNP-Transistors-GT308V-USSR-1980S-QTY-100-/161343038755?pt=LH_DefaultDomain_0&hash=item2590cb6523

Thanks for the fast reply!!!

[LucifersTrip]

i'm looking for a simple schematic for a fuzz with germanium MP-41.

honestly, can't give a schematic/recommendation without knowing gain/leakage of your specific transistor. ge stuff should be measured. can only give guess based on data sheet.

i'm not familiar with the soviet transistors,are they better??

there is no such thing as better...only better for a specific circuit. the 3rd model you listed above, GT308V, will generally be more useable in more fuzzes than the others you linked. but, like tjdracz wrote, the Russians are generally low leakage, so not good for the bunch of fuzzes that need that.

[george79]

so,continue with the ac-128 and leave the russians???

[tjdracz]

so,continue with the ac-128 and leave the russians???

By no means, they are quite good and work with a number of circuits like Fuzz Face, Rangemaster, Buzzaround... Plus you can get them quite cheap. I would leave alone the ones you've linked though as they are quite low gain normally and thus not that usable. Get yourself something like GT402, GT108 or MP20 if you want to get some germanium trannies, had excellent results with them

[LucifersTrip]

so,continue with the ac-128 and leave the russians???

By no means, they are quite good and work with a number of circuits like Fuzz Face, Rangemaster, Buzzaround...

only good for Q1/Q2 in Buzzaround...Q3 needs leakage

Plus you can get them quite cheap. I would leave alone the ones you've linked though as they are quite low gain normally and thus not that usable.

that's not correct...the 3rd one linked, GT308V, is one of the most common Russians used for no-leak fuzzes. The gains are ideal, usually in the 60-100 hfe range (common 70-80). I purchased 300-400 over the past few years and very few fall outside that range, especially the military grade ones, labeled, I believe "1T308В".

I bought a bunch from this guy in 2011
http://www.ebay.com/itm/1T308V-GT308V-PNP-120M-Germanium-Transistors-AF109-20pc-/370757168748?pt=LH_DefaultDomain_0&hash=item5652d96e6c

[tjdracz]

so,continue with the ac-128 and leave the russians???

By no means, they are quite good and work with a number of circuits like Fuzz Face, Rangemaster, Buzzaround...

only good for Q1/Q2 in Buzzaround...Q3 needs leakage

Plus you can get them quite cheap. I would leave alone the ones you've linked though as they are quite low gain normally and thus not that usable.

that's not correct...the 3rd one linked, GT308V, is one of the most common Russians used for no-leak fuzzes. The gains are ideal, usually in the 60-100 hfe range (common 70-80). I purchased 300-400 over the past few years and very few fall outside that range, especially the military grade ones, labeled, I believe "1T308В".

I bought a bunch from this guy in 2011
http://www.ebay.com/itm/1T308V-GT308V-PNP-120M-Germanium-Transistors-AF109-20pc-/370757168748?pt=LH_DefaultDomain_0&hash=item5652d96e6c

1T308V yes, but not GT308. We've measured a number of them with guys on the other forum and gains were lower than 50 more often than not,20-29 bag filled quite quickly

[LucifersTrip]

1T308V yes, but not GT308.

G = 1,  B = V.  Look at the box in the link



Of course it's possible you got a dud batch, but not common...here's a test from this forum of the GT308B



from the EXACT seller he linked to:
http://www.diystompboxes.com/smfforum/index.php?topic=83389.msg692902#msg692902

[rocket8810]

lucifer, i had similar experiences to tj with the gt308v vs 1t308v. it may be that recently the amount of really good ones had dropped, but i purchased both gt308v and 1t308v, and the gt's i've gotten have ranged as low as 10hfe to as high as 99hfe, with the vast majority of them in the 30-40 range, while the 1t308v's have been from 50-99hfe with the majority in the 60-80hfe range. i probably have about 100 or so of each, so my experience with them isn't as good as yours, but i've found for high hfe germaniums these are not the way to go.

Organized gt308v


Organized 1t308v


george, i've got a bunch of russians, and i've used the mp41's in everything from mark 1, mark 1.5, and mark 2 tonebender type circuits and fuzzfaces, to rangemasters and such. each of the russians have a different sound, so i would say if you can get a few different types for check go for it and experiment to find what you like. some of them clip softly, some more harsh almost silicon like, and most of the ones i've played with are more dark sounding compared to european, american, and japanese germaniums.

also, as a side note there is no best, just what sounds good to you, as we all hear things a little differently and have our own ideas of what's good and bad. it took me awhile to really realize that, and R.G. really got me to see that when he was helping me with a circuit i was designing and gave me some suggested reading. try to get out of the habit of thinking like that in relation to circuits and components, it will make it much easier to find what you're looking for.

[LucifersTrip]

lucifer, i had similar experiences to tj with the gt308v vs 1t308v.

We're talking about the specific link that the OP put in his 2nd post.  That's what he asked about....and those have been
confirmed good numerous times.
http://www.ebay.com/itm/Germanium-PNP-Transistors-GT308V-USSR-1980S-QTY-100-/161343038755?pt=LH_DefaultDomain_0&hash=item2590cb6523

If you have another link you can share that has confirmed poor gain ones, by all means post it so we can avoid them.

[rocket8810]

That's where I got mine. I'm not saying the ones I got were bad, just that they were not as good as expected, and I think it's important to talk about transistors on general then just from one supplier, because they're not always going to be the same every time, that's an unrealistic expectation with these kinds of parts. I've bought from gordelux and other sellers multiple times and sometimes they have been amazing, sometimes not as amazing. It happens with germanium. And it's also been well confirmed that the military spec ones are more reliable and consistent. I don't want to get into an argument or anything about it, it's just a fact about the military ones vs consumer grade germanium transistors.

Hell I have I gt109's with gains over 300hfe with almost no leakage, which shouldn't be, but they are and all of them are high gain >100hfe, but a lot of people I know haven't gotten anything like mine, it's just the nature of the beast with vintage and germanium.

[Finom1]

Hello,

I found someone on eBay selling the + 50pcs 1T308V ~ 2N2048 (Russian1Т308B) - Germanium vintage transistor USSR - https://www.ebay.com/itm/174668870744

I contacted him, and he said he has one lot left that is not listed at this time. Just email him and he will provide information.

Dmytro, is great to talk to and has a lot to offer on his ebay store. The price is right!!!

[Rob Strand]

LucifersTrip was a very industrious guy.   He's probably weeded through the details on over one hundred of those old pedals.