News:

Forum may be experiencing issues.

Main Menu

Need Pinout for Russian gt 403 trannies for my zygote build

Started by ch1naski, February 17, 2013, 05:10:09 AM

Previous topic - Next topic

ch1naski

I can't for the life of me find any info on these that isn't in Russian. That wouldn't be a problem,  except that it's all images of datasheets, and therefore can't use Google translate. Any one have any experience with these?

Sent from my Nexus 7 using Tapatalk HD
one louder.

midwayfair

http://www.radiomuseum.org/tubes/tube_gt403.html
This one's in German, but you should be able to figure out the picture. :)

FWIW, many Russian PNPs are this same pinout.

If it helps, in Russian the letter that looks like a lowercase b with a hook on it is a B (for base), the long word starting with K is the collector, and the first letter of emitter begins with a letter that looks like a 3. If there's a fourth pin, it'll be marked with a word that looks like kopnys ("corpus" = body), which is the case (for ground).

ch1naski

that explains why couldn't get the darn things to test right for leakage: base and collector are swapped around.

Thanks for pointing me there, you rock.8)

Sent from my Nexus 7 using Tapatalk HD
one louder.

ch1naski

Omg....the lowest reading I've gotten, out if the ten I bought, is 0.5mA .
Some were over 1.0.

Seems like the leakage prohibits any usefulness.....I would be looking for leakage under .03mA  for a decent fuzz-worthy germanium right?

I'm using the rg keen test method, the one with the 2.472k/2.2 meg resistor pair.


Sent from my Nexus 7 using Tapatalk HD
one louder.

culturejam

I've used some that had leakage in the 500µA range, and they worked fine. Hiss/noise seems to be hit or miss from piece to piece. I would suggest socketing the tranny pads and auditioning them by ear.
Partner and Product Developer at Function f(x).
My Personal Site with Effects Projects

ch1naski

Thanks. That's what I've been doing with the various black glass telefunkenand metal case sbxxx  trannies I've been grabbing out of old radios from the local antique fair. I've found that different transistors react very differently, tone-wise, in a rangemaster circuit. The af 105 I have sounds absolutely perfect,  except for the hiss.But that may be due to the 5% carbon resistors I'm using. Very woody tone, better than the oc44. I have a test rangemaster circuit just for switching out different transistors. :) I didn't realize how much effect the transistor could have on tone.......I thought it was all about the capacitors and resistors.

Sent from my Nexus 7 using Tapatalk 2
one louder.

midwayfair

The final transistor in some fuzzes sounds better with leakage -- to the point it occasionally needs to be *added* to get a good fuzz. Tonebender, Buzzaround, those sorts of things. If any of the ones you have are also low gain, the Percollator can use a trash transistor in Q1 to great effect. Yet another reason to love that design ...

ch1naski

Now I understand why some of you guys buy these things in lots of 100 or more: increases the odds of getting a few good ones.
I bought 10, hoping to at least get a couple decent q1 trannies for ff circuits, or a nice quiet 100hfe for a rangemaster.
Now I'm gonna have to build a tone bender. ;D that percolator seems pretty raunchy, I dunno if my kid would be into it. (Most fuzz-ish stuff I build goes to him, he digs Jimmy and Jimi. Good kid. ;) ) I'm more of a boost/overdrive/woody tone guy.
Sorry for the tangent...:P

Sent from my Nexus 7 using Tapatalk 2
one louder.