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DIY Stompboxes => Building your own stompbox => Topic started by: asilker on November 10, 2015, 03:47:34 PM

Title: Fuzz face help
Post by: asilker on November 10, 2015, 03:47:34 PM
Had an old BYOC fuzz face that I mangled as a teenager, decided to go back and try my hand at fixing it. Totally disassembled it so that I could trim the crazy long leads and fix the blobby solder. Things look much better now.

However I'm having trouble engaging the circuit. The LED lights up and the clean bypass works. However when I click the switch it still gives me the bypass sound. I've been trying to fix this for days now and I feel like I'm losing my mind.

Aside from the obvious "is the wire going to the correct place" comments, is there anything out of the ordinary I should be watching out for?
Title: Re: Fuzz face help
Post by: mcknib on November 10, 2015, 03:54:22 PM
Best to put some pics up both sides of the board and offboard wiring to the 3pdt switch etc if'n we can see it we may be able to spot something.

It's hard to say whether your board IN and OUT's may be going to the wrong place on the switch it's easy done when the pedals the wrong way up putting your IN jack tip to the OUT jack side on the 3pdt but as far as I can remember that'd give you bypass and nothing in effects mode it could be many things so if you can wack a picture up 

Debugging info here:

http://www.diystompboxes.com/smfforum/index.php?topic=29816.0 (http://www.diystompboxes.com/smfforum/index.php?topic=29816.0)
Title: Fuzz face help
Post by: asilker on November 10, 2015, 03:57:33 PM
Thanks for the reply :) (http://images.tapatalk-cdn.com/15/11/10/ff14186277fc580b902db5d0cf457159.jpg)(http://images.tapatalk-cdn.com/15/11/10/f2d647bd6503b0b765265f281ecea3b2.jpg)

The pedal is so simple, I feel embarrassed for spending so much time to no avail
Title: Re: Fuzz face help
Post by: mcknib on November 10, 2015, 04:06:38 PM
I wouldn't feel embarrassed not at all we've all had troubles with circuits simple or not I'll have a gander
Title: Re: Fuzz face help
Post by: mcknib on November 10, 2015, 04:39:49 PM
If the build docs the same it looks to me like your 4K7 and 470R resistors are mixed up the one next to the out pad should be 470R (yellow purple brown gold.) going to Q2's collector and the one next to the 2u2 cap should be 4K7 (yellow purple red gold) I'm no expert but I think that'd affect your fuzziness some, so swap those two around 4K7 is effectively 10 times the resistance to Q2C.

I take it your LED's pretty bright?
Title: Re: Fuzz face help
Post by: asilker on November 10, 2015, 08:47:07 PM
Ok I'll check that out tomorrow. I checked the DC voltage and the LED is getting around 7 volta
Title: Re: Fuzz face help
Post by: mcknib on November 10, 2015, 11:15:40 PM
That's a lotta voltage mine are usually 1.7 to about 2.5v using a 3K3 to 4K7 CLR.

Basically tells you that your CLR is letting more power through to your LED so hopefully when you swap those 2 around you'll get more juice to your transistor and less to your LED! and it'll work just fine when biased correctly hopefully that'll be your only problem.

What is your Q2 collector voltage? must be under a volt? causing the transistor to not function as it should ideally you want around 4.5v or per the build doc anywhere between 3.5v to 6.5v

Meant to say these are the build docs I used:

http://moodysounds.se/wp-content/uploads/2014/09/esvfuzzinstructions.pdf (http://moodysounds.se/wp-content/uploads/2014/09/esvfuzzinstructions.pdf)