Please help troubleshoot a Fuzz Factory clone

[MiguelDamas]

Hello everyone.

This is my first post (great forum btw) and also my first build and I find myself in a bit of a pickle. I wired everything up, but this thing will not pass signal, either turned on or off - although the LED does light up.

Here's the rest of the info based on the troubleshooting template:

1. Name of the project:

The Factory (Fuzz Factory clone) from Musikding


2. Links to the source of the project web site with the schematic or project, layout and wiring diagram:

Parts list:
http://diy.musikding.de/wp-content/uploads/2013/06/factorybomen.pdf

Schematic and PCB:
http://diy.musikding.de/wp-content/uploads/2013/06/factoryschalt.pdf

Wiring layout:
http://diy.musikding.de/wp-content/uploads/2013/06/factorywire.pdf


3. Some candid admissions about how closely you followed the suggested layout, if any:

I followed the wiring diagram and made no changes whatsoever.


4. Any parts substitutions or modifications you made to the original.

I didn't make any changes, but Q3 is an AC125 contrary to what the parts list says.


5. Whether or not it's a positive ground circuit.

Negative ground.


6. What it does and does not do how it works; partially or not at all. For instance, if it lets no sound through; or if it makes a harsh, distorted sound only when you strum hard on the strings at full volume; or if everything is really, really low volume.

No sound at all, either turned on or bypassed. The amp stops humming as soon as I plug the cable into the output jack of the pedal.

Here are the measurements I took:

Battery: 9.05V


Q1:
C = 1.50
B = 0.62
E = 0.00

Q2:
C = 9.34
B = 9.22
E = 9.15

Q3:
C = 9.33
B = 9.15
E = 9.31

D1:
A = 0.00
K = 9.33

C5:
negative - 0.00
positive - 9.39

C4:
negative - 0.00
positive - 4.64

C3:
negative - 9.40
positive - 9.40

C2:
9.28 / 1.50

C1:
negative - 0.00
positive - 0.62

R1:
0.00 / 0.00

R2:
0.62 / 1.50

r3:
1.49 / 0

R4:
9.13 / 9.01

R5:
8.53 / 8.93

R6:
4.51 / 9.10

R7:
0.00 / 0.00

R8:
9.12 / 1.88


This being my first build I'm sure the soldering is far from ideal. Here's a pic:



And a link to a huge version if you want to have a real good look at my exquisite soldering:

HUGE PIC

Any help is much appreciated.

[MiguelDamas]

Right, so a couple of things I've found by following some of the troubleshooting steps found in http://www.geofex.com/fxdebug/newfx.htm

Here are the power and ground measurements I took:



The stab, drive and comp ground connections read just over 6K while the other two pots read 0. The switch and input jack numbers are through the roof (I got a couple of overloads even on the 2M ohm setting on my DMM).

Also, according to that link, the numbers I got for my Q2 and Q3 mean they're saturated?

[Jakub421]

Photo of your board doesn't work.

[MiguelDamas]

Photo of your board doesn't work.

Thank you. Should be fixed now.

[bloxstompboxes]

That link to the larger photo is still broken. However, give us a pic of the part side too, please!

[duck_arse]

your huge pic still gives 404 error. we can't see it.

welcome to the forum, and are you measuring ohms/resistance/continuity with the power applied? this is the wrong method, you must power down for ohms measures.

check carefully your "6" connection, I think if that were open, you'd get floating (all ~9V) readings.

[MiguelDamas]

That link to the larger photo is still broken. However, give us a pic of the part side too, please!

Hi.

I will take some more photos when I get home. In the meantime, I have fixed the link in the original post.

Here it is again anyway:

PHOTO

[MiguelDamas]

your huge pic still gives 404 error. we can't see it.

welcome to the forum, and are you measuring ohms/resistance/continuity with the power applied? this is the wrong method, you must power down for ohms measures.

check carefully your "6" connection, I think if that were open, you'd get floating (all ~9V) readings.

Hi there and thank you.

I measured resistance with the battery removed from the circuit. You mean the contact labelled "6" on the PCB, right?

[duck_arse]

yep, 6 on the pcb.

[jimilee]

Ok so, lets see a picture of the switch and the jack wiring. If we got no bypass, all the rest is mute at this point.


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[MiguelDamas]

yep, 6 on the pcb.

I'll redo the connections and measure again. Pardon my ignorance but where would I get ~9V readings? Following that troubleshooting guide, I only measured voltage where the positive wires connect (and resistance where the ground wires go). Where should I be taking voltage readings after I redo the wiring between "6" and the gate pot?

Thanks again.

[MiguelDamas]

Ok so, lets see a picture of the switch and the jack wiring. If we got no bypass, all the rest is mute at this point.


Sent from my iPhone using Tapatalk

Will post later, thanks.

[MiguelDamas]

Considering my complete lack of experience I decided to get down to the absolute basics and make sure I at least get the thing to pass signal when it's switched off.

This is what the switch looks like at the moment:



The input jack:



And the output jack:



I've tested the switch and there is continuity between the middle row and the top and bottom rows depending on the switch position. I have also confirmed there is continuity between the input jack and the output jack regardless of switch position, but still no sound whatsoever.

The cables are working fine btw.

Thanks for your help so far.

[jimilee]

It doesn't look like either of your jacks are grounded


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[MiguelDamas]

It doesn't look like either of your jacks are grounded


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Right. So I wired input jack tip to output jack tip and sleeve to sleeve and verified continuity between them but it's still dead quiet.

I understand this is electronics 101 at this point.

[jimilee]

The grounds are the sleeve, not the tip.


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[MiguelDamas]

The grounds are the sleeve, not the tip.


Sent from my iPhone using Tapatalk

That's how I wired them:



They work fine outside the enclosure but not if I put them back in.

[cortezthekiller]

In your picture of the output jack (mono) mounted inside the enclosure it looked to be shorting out against the back of the pot.

[Tony Forestiere]

In your picture of the output jack (mono) mounted inside the enclosure it looked to be shorting out against the back of the pot.

Good eyes.  It looks that way to me too.

[MiguelDamas]

In your picture of the output jack (mono) mounted inside the enclosure it looked to be shorting out against the back of the pot.

Thanks! That was it. I put electrical tape on the back of the pots (is this bad practice?) and now I get the guitar signal on the output jack.

I will rewire the switch and take it from there.

There is hope!