Which Fuzz to Build?

[enigmur]

So I want to build a fuzz circuit next.

I would like a Hendrixy fuzz, but can be toned down to be really creamy sounding drive aswell.

The Axis Face looks good to me, and doesnt look too hard - plus it is on vero.

http://www.indyguitarist.com/torchy/Distortion_Overdrive/Axis%20Face%20-%20Si/Axis_Si.gif

Is this a good fuzz to go with? Any better suggestions?

Looking at the transistors, can I use something else here? If not I'll have to get them from overseas.

Also what sort of Pot's is it using?

The build doesnt look too far over my head, and I'd love to have a fuzz to use myself or give to the rhythm guitarist.

Any suggestions or ideas would be a help -
Cheers

[Meanderthal]

 Yep, go for it, that's a good choice for what you describe.

Funny thing, someone was very recently searching for that exact layout round here...

[tcobretti]

Read this which is where the Axis Face came from:

http://fuzzcentral.ssguitar.com/axisface.php

[enigmur]

Yeah should be exciting to build. I'll put it in a bright orange case and call it Ginger Muff.

Looking at the schem I'll just have to find the trannies and diodes, or something that can be used instead.

And is a trimpot the same as a preset variable resistor? Sounds to me it's the same thing but the local component shop doesnt call them trimpots.

[Meanderthal]

 HUH ? Preset variable resistor? Yeah, I guess you could call it that, it's a small set-and-forget pot intended to be mounted on the circuit board.

R7, R8, and R9 are the external pots.

[tcobretti]

Note that on that layout the smooth pot is a trimpot, but I think the creator's intention is that it be an external pot. 

That said, on my Si FF I made it a socketed resistor and swapped values until I found one I liked.

[enigmur]

What are the differences between pots?

I used linear on my boost pedal, can I use linear again on this?

[tcobretti]

Linear vs. Audio has to do with the sweep of the pot, and they are usually interchangable, though the wrong taper may not work as well.

Trimpots are small pots that mount to the circuitboard and are adjusted with a screwdriver.

[enigmur]

Cool thanks for the info.

I can't find those transistors on the local site, anything I can substitute them for?

Doesn't this board use diodes at all?

And what are those white squares with red dots in the layout diagram? Cheers.

[petemoore]

Cool thanks for the info.

I can't find those transistors on the local site, anything I can substitute them for?
  Yes...low gainer for Q1 or any NPN si or Ge really, you're building the NPN neg gnd I assume, socket the transistors, does this use a trimpot for Q2C resistor?
  This is a great fuzz box, higher gain transistors will make it...higher gain, will be 'large' in the fuzz dept. probably won't do guitar volume cleanup as cleanly.
Doesn't this board use diodes at all?
  You could can put a polarity protection diode for reversed battery if you like, I don't think it need signal clipping diodes.

And what are those white squares with red dots in the layout diagram?
  Those must be the trace cuts, slowly drill the vero trace until it is completely cut, test with DMM, don't go too far with it, just enough to remove the copper.
  Get the schematic and make sure it matches some before drilling the trace cuts...if it's a verified layout, just count carefully, then cut.

[enigmur]

Hi thanks a lot Pete.

I have started building the fuzz, I just need to order a couple of Caps, the 2 trimpots, pots and maybe the transistors (depending how this question is answered).

Basically I have an old Crate Chorus pedal which had a dodgey switch in it, I gutted it and have been stealing resistors off it for my wah pedal.

I just found a 10nf capacitor on it (after learning how to read the value codes - 103K).

Now there are a bunch of transistors on it, I'd like to post a few of the codes from the transistors and see if they can be of any use in this pedal, or another pedal - if they are NPN or PNP (not sure what these actually mean).

Okay so here are the codes on the normal looking 3 legged type - how it appears on the trannie.

There are quite a few of this type -
C945
PI77C

Then there are two of -
CI328
R 75

There are also smaller square/pentagon shaped ones -
K44
C2G

Are any of these transistors any use to me? And what type are they?

Also, when reading values on capacitors, there are a few on here which don't seem to be the usual numbering system I mentioned before (like 104K, 223J ect...)
They are .047K and .1K - what are these in F?

Thanks for any help, I will send off my order once I know that sort of transistors these are and if I need to get different ones.
Then I just need to get my 3PDT switches from Aron when I'm ready 

Shopping List
Looking at the list, is 2u2F the same as 2.2uF?
I can only find a 100pf Surface Mount capacitor, would that work? I also looked for .1nF and couldnt find one.
The shop has Slide, Log, and Linear pots, which should I use? And what does it mean by 1K-B, 5K-B, 100K-A? (What are the letters?)
And what are some other Transistors I should search the shop for (if the ones on my chorus PCB wont do) because the shop doesnt have PN2369A.

Cheers for any help

[jlullo]

enigmur,
you don't any surface mount components... that's a whole other ballgame!

if you want the suggested transistors (per fuzzcentral)
PN2369A
BD139
i'll gladly put them in the mail for you.  just PM me your address

i ordered a bunch so i could do this project as well!

[enigmur]

I did a search on their site for BD139 and they have 100v versions of the transistor. I'll get some of these.

I still can't find a 100pf cap though. Would ceramic disk work? Because there is are 100pf ceramic.

I really want to get this order sent off

[MikeH]

For a fuzz, my opinion is (and others may differ) that a ceramic cap will sound find.  In things like compressors and delays and such where clarity and low noise are crucial, you would want film caps.

[enigmur]

Cheers for that, I'll try one out.

Anyone got any ideas on my previously posted question about the components on the PCB out of the chorus pedal?

[DanielWong]

Since were on the topic of Fuzz, has anyone build the Uglyface lately? Is the "hype" (I don't like using the word "hype" as this is DIY...but whatever) behind the circuit just because it can self oscilate into craziness just using the potentiometers? Other than that, does the actual fuzz sound good?

[tcobretti]

I just built it, and it is pretty cool.  I ran the freq knob to an expression pedal, and it serves as a weird synthy wah that also sounds cool if you leave it in a fixed position.

I don't think the fuzz would sound particularly cool by itself, but it is always running thru the 555 so the weirdness is always present.  I think it would be an amazing pedal if it could be clean with all the filtering/weird wah action.

I'll try to make some clips, and I'll start a new uglyface thread.

[enigmur]

Ok, sent away my order for parts just then, should have them tomorrow.

I also got a few extra bits just for if I need them (kid in a candy store).

Would still like to know some info about the transistors and caps I posted about earlier...

[petemoore]

I did a search on their site for BD139 and they have 100v versions of the transistor. I'll get some of these.

I still can't find a 100pf cap though. Would ceramic disk work? Because there is are 100pf ceramic.
  As long as the caps are rated for higher voltage than applied, they'll work.
  I lost track of the position of the cap, now I think it's a small value rolloff cap, and in that position, it might be hard to tell any teeny weeny differences compared to film types.
  I think mostly we're using non-ceramic types.

I really want to get this order sent off

[enigmur]

I got my order today.

The transistors I got are weird though. They are square and flat with a hole thru the middle. And the legs are thicker than usual, wide and flat. I think this may be because they are a high voltage rating?

Also the capacitors I got are square and flat, unlike the usual rounded red or green ones, these are just square and grey.

I think it will all work, if the trannies are right. But I might start ordering parts from SmallBear or something so I know what im getting...

Wish me luck!