well, i put a mangler together and guess what? that's right, it doesn't work. go figure ::) i'm still battin 1000 though! i'm only getting 1.6v at the bias test terminal. i think it's in the transistors. although i have the right resistors installed, i don't think the values are right fot these particular transistors. they are supposed to be pnp ge. the number on them is 2n1039. any thoughts? thanks a million in advance! ;D
You may want to test for leakage. All of my 2n1309's have extremely high leakage and gain. They are almost unusable in my tests. You may have different ones though. These are TI branded. I would also test with a pair of Si devices to make sure it isn't the transistors.
Quote from: JakeFuzz on January 23, 2013, 01:19:37 AM
You may want to test for leakage. All of my 2n1309's have extremely high leakage and gain. They are almost unusable in my tests. You may have different ones though. These are TI branded. I would also test with a pair of Si devices to make sure it isn't the transistors.
thanks for the response, JakeFuzz! these are marked with an "S" inside of an inverted triange, then 730. i am as green a newbie as you'll run across. so the next question is, how do i check for leakage? and what values am i looking for? Thanks for your time and patience. LT
http://www.geofex.com/article_folders/fuzzface/fffram.htm (http://www.geofex.com/article_folders/fuzzface/fffram.htm)
This document is like the bible of fuzz faces. About halfway down there is a guide to making a very simple DC tester for gain and leakage. It is only DC but lots of people use this method for characterizing transistors and it works pretty well. In reality you're going to have a logarithmically decreasing gain value as the frequency increases. I would say anything greater than 50-60 for gain and you should be fine. The leakage should be below about 700-800uA (or 0.7mA) in my experience. Anything above that and things get funky. Silicons are the way to go as far as testing is concerned. They should bias up just fine and pass sound to confirm everything else is solid with your build.
Quote from: JakeFuzz on January 23, 2013, 03:08:45 AM
http://www.geofex.com/article_folders/fuzzface/fffram.htm (http://www.geofex.com/article_folders/fuzzface/fffram.htm)
This document is like the bible of fuzz faces. About halfway down there is a guide to making a very simple DC tester for gain and leakage. It is only DC but lots of people use this method for characterizing transistors and it works pretty well. In reality you're going to have a logarithmically decreasing gain value as the frequency increases. I would say anything greater than 50-60 for gain and you should be fine. The leakage should be below about 700-800uA (or 0.7mA) in my experience. Anything above that and things get funky. Silicons are the way to go as far as testing is concerned. They should bias up just fine and pass sound to confirm everything else is solid with your build.
LOL! although your speaking greek to me now, i'm gonna check this out. i may or may not (more than likely) understand, but you can't learn if you you don't read. (read: "you can't win if you don't play") thanks a million! you're my horse if you never win a race! ;{D LT
2 resistors, a momentary switch, 9v, and a dmm its a really quick build.
i got a small radio shack project board and attached stand-offs in the corners
crack a op socket in half and you got a tranny socket
Quote from: jeffaroo on January 23, 2013, 03:48:47 AM
2 resistors, a momentary switch, 9v, and a dmm its a really quick build.
i got a small radio shack project board and attached stand-offs in the corners
crack a op socket in half and you got a tranny socket
got plenty of resistors, 9v battery and power supply (voodoo lab power2 plus) a pro dmm. not sure what you mean about "cracking an op socket in half". i have a bread board coming. i've nearly ruined a couple of MadBean pcb's so i thought i could use one...
yes you can use a breadboard if you like. i built this thing only cuz i use it all the time. i cracked a op amp socket in half as a place to plug the tranys into. the stand-offs on the board is like table legs. on the board i soldered a loop (like a upside down U) for +/- hooking in the dmm. whole project was like 3.00 plus scrap parts laying around
Quote from: jeffaroo on January 23, 2013, 04:05:03 AM
yes you can use a breadboard if you like. i built this thing only cuz i use it all the time. i cracked a op amp socket in half as a place to plug the tranys into. the stand-offs on the board is like table legs. on the board i soldered a loop (like a upside down U) for +/- hooking in the dmm. whole project was like 3.00 plus scrap parts laying around
cool breeze, Bro! i think i understand. i'll holler back when i'm ready to set it up. thanks a million!
;D
man i'm gettin close! i swaped trannys to 2n5087's, now i have a low rough growl at wide open vol and fuzz. i was also able to bias to -4.6v not real sure where to go from here. BTW, battery voltage was low (7.6v) so i replaced it (9.5v) and it actually worked better at the lower voltage.
beavisaudio.com
look for the voltage sag mod
you will like it ! ;D
Quote from: jeffaroo on January 27, 2013, 01:22:21 AM
beavisaudio.com
look for the voltage sag mod
you will like it ! ;D
i bet i would! just gotta get it going right first. thanks!
Quote from: TreeSlayer on January 27, 2013, 12:22:53 AM
man i'm gettin close! i swaped trannys to 2n5087's, now i have a low rough growl at wide open vol and fuzz. i was also able to bias to -4.6v not real sure where to go from here. BTW, battery voltage was low (7.6v) so i replaced it (9.5v) and it actually worked better at the lower voltage.
well, i've tryed all of the trannys in my arsenol, and 2n5087 works best. i have to turn all of the volume's up full, vol-fuzz on box, and full volume on guitar. it actually works best for several seconds when you first turn it on, then seems to fade away. if you turn down any of the three pots, it quits. i wish i could put some audio on here....
I'm guessing you've checked the resistor values to make sure nothing was swapped like a 100r for a 100k for example. It happens to the best of us.
Quote from: jimilee on January 28, 2013, 12:32:46 AM
I'm guessing you've checked the resistor values to make sure nothing was swapped like a 100r for a 100k for example. It happens to the best of us.
actually, i checked everything before i commited to solder. i learned this early on, not only to make sure the value's right, but also to make sure it works (got a hold of a bad one).
ya know, it just occured to me. once, when i was testing, i shorted out the battery when it was connected to the board. i didn't see or smell anything bad so i marched on. any thoughts?
I'm sure it has something to do with the weird ass wiring (+9v effect) , trying to figure it out now.
Quote from: jimilee on January 28, 2013, 01:07:18 AM
I'm sure it has something to do with the weird ass wiring (+9v effect) , trying to figure it out now.
i thinking the same thing. -9v f'cks with my head any way.