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LoveMyLesPaul
05-05-2006, 01:49 PM
I just built the arbiter fuzz face clone from fuzz central. I used the germanium transistors from smallbear, and the only thing I changed was using a 22uf cap in place of a 20uf cap in one spot because that's all I could find. I don't have a lot of soldering experience, so it's possible that something didn't make a good connection, my problem is this:

When bypassed, everything's fine. When I turn the pedal on (not in the enclosure yet, just carefully spread out on the floor) The sound gets slightly darker, but it's clean except for this loud clicking sound. Imagine you took a comb, bent all the teeth over with your thumb and then one by one let them snap back... but pretty loud through my amp. The fuzz pot just makes it click more, the volume pot slightly affects the volume, and also makes it click more (but the clicking is more bassy with the volume pot turned up, and more trebbly with the fuzz pot turned up). Did I make some common mistake? Please help a dumb guy out...

Sir H C
05-05-2006, 01:53 PM
Pictures? That would help a lot. That and if you have a volt meter measure the voltages throughout the circuit (base and collector of the first transistor and the collector of the second one).

LoveMyLesPaul
05-05-2006, 02:24 PM
Probably the first thing I should say is that I've never used a soldering iron before in my life. I'm sure the problem is something that I soldered wrong, so don't be surprised when you see how bad it looks :eek:

also, since asking the question I grounded the empty lug of each pot, and that helped a lot... the thing kinda almost works now, but the fuzz is really bad and last for like half a second before the signal is gone, and some notes don't even come across... like it goes in and out...

Here's the whole thing:
http://images5.pictiger.com/images/5d/aac119e2c04fe75fd167c2b64659375d.jpg

Here's the top of the circut board:
http://images5.pictiger.com/images/51/a113a5270b47e55762bdedd48b11a251.jpg

And here's the bottom with the horrible soldering:eek: :
http://images5.pictiger.com/images/57/a5dc1661ee9ec95841e5c1f08c53dd57.jpg

LoveMyLesPaul
05-05-2006, 02:40 PM
OK, on the first transistor (measuring with the positive lead on the positive battery terminal for ground, and the negative lead doing the probing... is that the right way? it's PNP I think...)

on the Emitter I have 0,
on the base I have 0.1
and on the collector I have 0.29

On the second transistor:
on the Emitter I have 0.3
on the base i have 0.29
on the collector i have 8.4

on the package the transistors came in it says:

tested with:
R3 30k (mine's 33k)
R4 680ohm (mine's 470ohm)
R5 8.2k (mine's 8.2k)
R6 100k (mine's 100k)

it says these values will put the collector of Q2 at 4.5 volts with a 9 volt power supply.

but I have 8.4...

Sir H C
05-05-2006, 02:45 PM
Looks like you have a short between the base and emitter of the second transistor. That would be the first thing to look at.

LoveMyLesPaul
05-05-2006, 02:55 PM
Looks like you have a short between the base and emitter of the second transistor. That would be the first thing to look at.

Thanks! I checked it with the ohmmeter and it says 120ohms between the base and emitter. is that shorted?

I also just watched that how to solder video... and realized I was supposed to solder the leads TO the pads... doh!

Sir H C
05-05-2006, 03:05 PM
It is hard to say if 120 ohms is a short or not. I would say yes, because it is pretty definite that the second transistor is not "on" but there is current running through the emitter resistor to pull that up to .3volts. Where is it coming from? Most likely the base connection to the 33k resistor.

LoveMyLesPaul
05-05-2006, 04:21 PM
First of all thanks so much for your help!

Let me make sure I understand I need to find where there's a short in the rectangle I've drawn? or could there be a short inside the transistor? Like if I got it too hot while soldering (very possible)? It looks a lot cleaner in real life than these pictures, I can't see anything on either side between the base and emitter.

What's the next thing I do?

http://images3.pictiger.com/images/d4/f3a480def0613d25efc2c08d517611d4.jpg

RoboPimp
05-05-2006, 04:56 PM
you might try a new transistor and maybe socket it.