Zvex - Fuzz Factory

trad3mark · Post by **trad3mark** » 26 Apr 2009, 12:26

ok, so, since yesterday, i found a few loose wires etc, fixed them up, but still nothing. I think it's an issue with the switch. yet again, i'll post my wiring, cos it all seems to be in order.

ALSO, before i do, i figured out how to explain my whole transistor flipping issue. Basically, because i cut the tracks backwards so to speak, the transistors aren't flipped, they'red just backwards to coincide with the circuit. It's as if my layout is flipped like.

Anyway, here's my wiring, any help would be awesome...

Input Jack:
Ground > Master Ground (on board, a line where all my grounds go to)
Switched > -ve on BATTERY CLIP
Hot > Switch 5

Output Jack:
Ground > Master Ground
Hot > Switch 6

Switch:
The switch is laid out like this:
1 2 3
4 5 6
7 8 9

where the poles are going like this - - - and is based on this: http://www.generalguitargadgets.com/dia ... attery.gif
1 > Nothing
2 > Switch 3
3 > Switch 2
4 > Master Ground
5 > Input Hot
6 > Output Hot
7 > Stab 1, via an LED and 2.2k Resistor
8 > Circuit Input (Hole e25 on layout)
9 > Circuit Output (Hole c1 on layout)

Pots:
Volume:
1 > Master Ground AND Gate 3
2 > +ve of C1 (hole a1)
3 > 5.1k (hole b1)

Gate:
1 > Gate 2
2 > Gate 1 AND 470R (hole a7)
3 > Volume 1

Comp:
1 > 10k (hole a17)
2 > Comp 3
3 > Comp 2 AND Drive 3 AND 47k (hole a11)

Drive:
1 > Stab 3
2 > -ve of C2 (hole b24)
3 > Comp 3

Stab:
1 > +ve of BATTERY CLIP AND Switch 7 via Resistor 2.2k and LED
2 > Stab 3 AND +ve of C2 (hole a24)
3 > Stab 2 AND Drive 1

I've checked and double checked. I'm going by the same layout redraw. Just to double check, in that redraw, all the pots are 3 2 1? like it's as if you're looking at the back of the pots, right? Also, oddly enough, i did the whole thing of touching the various contacts, looking for that sort of grounding hum. It's there at the end of the circuit, where output is... so my guess (although i'm still quite a noob at electronics) is that power/signal is going through the circuit...

trad3mark · Post by **trad3mark** » 26 Apr 2009, 15:18

oooh! progress!

ok, so i've noticed now that when i put my fingers on certain points, i get noise. Not fuzz, noise. Like the signal's coming through, but just getting screwed along the way. I think there's a few bad connections.

trad3mark · Post by **trad3mark** » 27 Apr 2009, 01:01

as if i couldn't get any closer...

i'm now at a stage where it basically works. however, when i start to put it in the box, i literally get to the last bit. The LED and switch went in first, test run, works. Then the pots went in, one by one, test, works. Then the input and output jack, tested, works. Then finally, the circuit, and it dies. Now, it's not entirely dead, only semi dead. When the circuit board is in certain positions, it all works fine, but, when i go to mash it in and all the wires, it dies. So, somewhere, some wires are crossing... any suggestions to combat/prevent this?

soulsonic · Post by **soulsonic** » 27 Apr 2009, 07:26

trad3mark wrote:When the circuit board is in certain positions, it all works fine, but, when i go to mash it in and all the wires, it dies.

There's the problem. One of the wires either has an intermittent break in it, or one of them is shorting against something.
I say have it all outside the box and working, and then carefully bend each wire individually to find which one has the break. If that doesn't work, then carefully inspect each one for missing insulation where wire is exposed and potentially able to short against things. I also recommend having all the wires be as short as possible.
Neatness is important when there's alot of wires.

ShortScaleMike · Post by **ShortScaleMike** » 27 Apr 2009, 08:31

Good advice. Also any connections you can make between the pot lugs themselves rather than going to common places on the board is to be recommended. When I made mine I drew up a layout and minimised all the wiring to the board, I think I got it down to around 4 wires to the Pots.

Crimson · Post by **Crimson** » 27 Apr 2009, 15:10

I'm sorry, i've searched in this topic but i only can find an approssimative answer.
I would like to know HFE of Q1, Q2, and Q3...
just the schematic to know the trannies i'm talking about:

Thanks in advantage for your help!

Crim

trad3mark · Post by **trad3mark** » 27 Apr 2009, 15:28

Q1 is a capacitor in that schem... and, afaik, it's a 0.1uF. As for the transistors, the 2N3904 is the same in all the layouts. Originally, AC128's were used for the other two, but there's a bunch of altenativels, like BC558, NTE158, OC44 or NTE126.

Scruffie · Post by **Scruffie** » 27 Apr 2009, 16:00

trad3mark wrote:Q1 is a capacitor in that schem... and, afaik, it's a 0.1uF. As for the transistors, the 2N3904 is the same in all the layouts. Originally, AC128's were used for the other two, but there's a bunch of altenativels, like BC558, NTE158, OC44 or NTE126.

Q1 is a capacitor ???

Anyway as for the original question, seeing as this is a fuzz face with a boost stage stuck on basically, the 2N3904 isn't too critical for hFe i don't think, as for the Germanium PNP's (or silicon if you decide germaniums are too expensive or hard to find) seeing as it's a fuzz face i would probably read through this article http://www.geofex.com/Article_Folders/ffselect.htm for info on choosing them for the correct hFe, some people have different preferences though, can always socket the transistors and go by ear for what you feel sounds best.

trad3mark · Post by **trad3mark** » 27 Apr 2009, 16:11

seriously, this pedal is throwing everything at me not to get finished. I don't know what happened, but it's now a volume pedal lol!

i have true bypass, but when i turn it on, volume works, but i have no fuzz. double checked all the wiring, it all looks spot on. ideas??

beans1 · Post by **beans1** » 28 Apr 2009, 05:14

Maybe this will help out http://www.fennecelectronics.it/Chitarr ... Factor.htm I just built one for a 12 year old kid down the road and it works.

trad3mark · Post by **trad3mark** » 28 Apr 2009, 12:26

nah i think it's just a dodgy contact on the gate pot. It's annoying only finding out now that even if a wire is soldered onto the contact, sometimes a proper contact isn't being made and it's as good as not being soldered...

Scruffie · Post by **Scruffie** » 28 Apr 2009, 12:35

If it's a good contact it should be shiny, if it's a cold joint i.e. it isn't gunna work it'll be murky and dull coloured, also, the problem with solid core wire is it can break at the end but still stay attatched annoyingly, just one of those things, can try braided wire if you prefer.

trad3mark · Post by **trad3mark** » 28 Apr 2009, 15:41

i'm working on a history project at the moment, but, i'm fairly sure the problem's with the gate pot. When i was working on it last night, i was getting crackling when i moved the gate wires. i didn't get that with the other pots at all, so that kinda suggests that the problem lies at gate, right?

Scruffie · Post by **Scruffie** » 28 Apr 2009, 16:32

Could be a good place to start, just rewire them i guess and see if that sorts it.

trad3mark · Post by **trad3mark** » 28 Apr 2009, 20:37

ive checked and checked the soldering at gate. still just the odd crackle. i'm tempted to give up at this stage...

Scruffie · Post by **Scruffie** » 28 Apr 2009, 20:41

You can't give up now, you had it fuzzing away before, you can get it fuzzing away again, i'm sick to death of my dr boogey having a signal and seemingly working controls but no distortion! but just gotta keep at these things, you will get there eventually, maybe start from fresh but it can be done, just keep poking.

trad3mark · Post by **trad3mark** » 28 Apr 2009, 22:47

i have intermittant fuzz, which isn't good enough. i'm rewiring all the pots..... AGAIN. ffs

beans1 · Post by **beans1** » 29 Apr 2009, 03:37

Has any one tested the transistor gain in the original Fuzz Factory?
If it has been posted and i messed it please direct me to it and sorry for asking but i did do a search that turned up nothing or again i messed it some were.
I think im going to order some 128 from banzaieffects.com
Thanks.

trad3mark · Post by **trad3mark** » 29 Apr 2009, 16:46

arrrrgh! i've lost my LED indicator!! bad sign!

trad3mark · Post by **trad3mark** » 30 Apr 2009, 11:30

i think i've managed to break another switch. If i want to JUST test the fuzz circuit, could i run the input from the jack into the input of the circuit and the output of the circuit to the output of the jack, so that when the amp is on it's JUST the fuzz circuit?

Zvex - Fuzz Factory [traced]