Mad Bean Pedals Woodstock User manual

woodstork
FX TYPE: Fuzz
Based on the Fulltone® ‘69™
© 2016 madbeanpedals
1.7” W x 1.925” H
Terms of Use: You are free to use purchased circuit boards for both DIY and small commercial operations. You may not offer these PCBs for resale or
as part of a “kit” in a commercial fashion. Peer to peer re-sale is, of course, okay.

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R1 1M C1 2u2 D1 1N5817
R2 100k C2 100pF
R3 33k C3 22uF Q1, Q2 PNP
R4 220R C4 100n
R5 4k7 C5 47uF IC1 TC1044SCP
A
R6 1k C6 100n
R7 1M C7 10uF T1 10k
C8 10uF
CONT 1kB
FUZZ 1kC
BIAS 50kB
VOL 500k
A
IC
Trimmer
Pots
B.O.M.
Resistors Caps Diodes
Transistors
V
alue QTY Type Rating
220R 1 Metal / Carbon Film 1/4W
1k 1 Metal / Carbon Film 1/4W
4k7 1 Metal / Carbon Film 1/4W
33k 1 Metal / Carbon Film 1/4W
100k 1 Metal / Carbon Film 1/4W
1M 2 Metal / Carbon Film 1/4W
100pF 1 Ceramic 16v min.
100n 2 Film 16v min.
2u2 1 Electrolytic 16v min.
10uF 2 Electrolytic 16v min.
22uF 1 Electrolytic 16v min.
47uF 1 Electrolytic 16v min.
1N5817 1
PNP 2 PNP Germanium Transistors
TC1044SCPA 1or, MAX1044CP
A
10k 1 Bourns 3362P
1kB 1 PCB Right Angle, Plastic Shaft 9mm
50kB 1 PCB Right Angle, Plastic Shaft 9mm
500kA 1 PCB Right Angle, Metal Shaft 9mm
1kC 1 PCB Right Angle, Metal Shaft 9mm
Shopping List
Note: 10n is the typical value for C4 used in Fuzz Faces, but it seems to be 100n in the ’69.

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1590G Drill Guide
3.66”W x 5.63”H
LED can be mounted directly to the PCB. Drill spot is directly above the “LED” text.

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Overview
The Woodstork is a PNP Fuzz Face with the Fulltone® ’69™ mods incorporated. It also includes a charge pump to invert
the supply voltage so that a regular 9vDC negative tip supply can be used for power.
Controls
Vol: Output level.
Fuzz: Fuzziness.
Bias: Adds series resistance at the circuit input.
Cont: Adds extra volume at the output.
T1: Sets the bias on the collector of Q2.
Notes
Space is limited in these 1590G builds so I recommend going with T0-5 (“top hat”) style PNP transistors. These should be
soldered flush to the PCB without sockets. You should be able to use other styles of PNP transistors, as well. If using
transistors that are too large to fit on top of the PCB (so that the enclosure lid will actually close) then you can solder them
to the bottom of the PCB instead. You may need to fold them over a bit to fit in that space, though.
Smallbear has many verities of PNP transistors including matched pairs for the Fuzz Face:
http://smallbear-electronics.mybigcommerce.com/fuzz-faces-and-similar/
These often include resistor values used to bias the transistors in a Fuzz Face. I recommend using the values listed in the
BOM to build the Woodstork.
“Bias” pot: This is not a true bias control…it’s just called that because reasons. When turned down it behaves similar to
rolling the volume pot down on your guitar. People find this control useful because the Fuzz control tends to get murky
when turned down. Leaving the Fuzz mostly all the way up and turning the Bias control all the way down is a way to
reduce the total fuzz without things getting muddy.
The Cont pot (short for “Contour) does not do much in the way of tone shaping but it will add extra volume output. With
the Cont pot halfway up it is about the same output as a regular Fuzz Face. Turning it up further will give you some more
dB to work with at the Volume control.
Biasing
Biasing the Woodstork is very easy. Using your multimeter, attach the black lead to a ground point on the PCB. Touch the
red lead to the “TP” pad on the Woodstork. Now adjust the T1 trimmer until you get a reading of about -4.5vDC.
Remember, the power here is inverted so you are supplying -9v to the circuit via the charge pump and adjusting the Q2
collector for -4.5v.

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