StewMac SUN FUZZ Manual

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SUN FUZZ
UPGRADED FUZZY-FACED CLASSIC
INSTRUCTION GUIDE

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BASED ON THE ANALOGMAN SUNFACE
FIRST TIME BUILDING A PEDAL? Kick back and watch our 4-part
series where we show you the basics of pedal building. Even if
you’re a complete beginner don’t worry! We go over everything
from unboxing, to choosing the right soldering iron, to making
every connection. We also give tips on painting your pedal.
Visit: stewmac.com/pedal-build
This kit nds its roots in the classic Fuzz Face, which while very popular, isn’t the most easy-to-get-along-with fuzz pedal on the
market. Eventually, Analogman’s Mike Piera went about ne-tuning the original circuit to make it more friendly and consistent
with a little bit of work from the player dialing in the pedal with their guitar and amp. Mike calls this pedal the SunFace.
Based on the BC-108 version Analogman SunFace, the Silicon BC-108 transistor provides a brighter tone, higher gain, and
temperature stability that Germanium transistors do not have. And at a lower cost to boot. This transistor rst started
appearing in the Fuzz Face around 1969 as a replacement for the nicky Germanium components. In addition to the standard
Volume and Fuzz controls, the Sun Fuzz also features a tone control to further dial in the desired tone.
The SunFace is still being made by Analogman but is subject to long lead times and high resale prices. Currently listing on the
used market at around $500 as of 1/22.

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Soldering Iron #0502
Solder Wick #0504
Solder #0505
Wire Cutter #1607
Long-Nose Pliers #1610
Fine-Gauge Wire
Stripper #1606
Guitar Tech
Wrench Set #3691
or nut drivers/sockets
PC Board Holder #0500
TOOLS AND SUPPLIES
REQUIRED OR RECOMMENDED
Not pictured: #1 Phillips screwdriver,
and supplies to paint your pedal, clear
silicone adhesive, spray nish.
Power: Model 12252 requires a
standard 9V DC center-negative
power supply (not included) and
consumes less than 100mA.

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Magnifying glass or
OptiVISOR #1685
Multimeter PM16B #3607
Our Pedal BuildingTool Set #2318 is the
perfect companion for new pedal builders
who do not already have a lot of tools and supplies.
TOOLS AND SUPPLIES
HELPFUL
Soldering Aids #0521

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We know you are excited to get started building.
That said, one of the keys to a successful build, is
taking the time to get to know all of your parts. Sort all of your pedal’s
parts and check o according to the parts lists that follow. If you are not
familiar with what they do, the next section will give you a little primer.
1K resistor (1) #7357
Brown Black Black Brown Brown
Brown Black Black Orange Brown 100K resistor (1) #7365 Orange Orange Black Red Brown
33K resistor (1) #7409
Yellow Violet Black Brown Brown 4.7K resistor (1) #7359
Yellow Violet Black Black Brown
470Ω resistor (1) #7355
1N5817 rectifier diode (1)
#7522
22µF capacitor (1)
#7311
22uF
1µF capacitor (1)
#7337
1uF
47µF capacitor (1)
#7478
47uF
10nF capacitor (8)
#7331
WIMA
0,01
100-
PARTS LIST
Note: While electrical
properties remain the same,
the appearance of parts may vary
based on availability. If you are ever
unsure, please contact us via the
information on the back of this manual.

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50K trim pot (1)
#100739
503
5K trim pot (1)
#100738
502
BC-108 Transistor (2)
#101123
30" of 22 guage lead wire (1)
#101978
5mm white LED (1)
#7422
5mm LED mounting bezel (1)
#7432
2.1mm DC power connector (1)
#7468
B1K linear taper pot (1)
#7451
B5K linear taper pot (1)
#7452
A250 audio taper pot (1)
#7531
3PDT latching footswitch (1)
#1611
PARTS LIST CONT

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Circuit Board [PCB] (1)
Breakout Board (1)
Sticker sheet (1)
Pre-drilled enclosure (1)
IN GND SW OUT
Control knobs (3)
#7501
1/4" mono jack (2)
#4652
PARTS LIST CONT

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1. To minimize redoing steps, make
sure you have a solid idea of the
look and feel you’re going for.
2. Lightly sand housing with a
P240 grit sandpaper and wipe
clean any debris.
3. Cover the holes from the
inside with masking tape.
4. On a large piece of cardboard,
elevate the housing top and
bottom on a couple of small blocks
of wood.
5. With long, slow strokes, spray
one light coat of primer or primer/
paint on top and bottom. Allow
45 minutes of drying time between
next two to three coats.
6. If you’re using primer followed
by paint method, paint 3 coats
with 45 minutes between coats.
7. Now, add your Sun Fuzz
sticker and any other
desired decoration (paint
pens, acrylic paint, Sharpie
etc.). Allow drying time.
8. Add 3 coats of clear coat glaze
with 45 minutes between
coats. Wait at least 2 hours
before adding parts.
Give your pedal a custom paint job by painting and adding the stickers provided in this kit
(or custom decals that you can create on your own). Doing this pre-build is not only fun,
but it’s much easier than disassembling the pedal to paint it once you put it together. Don’t
forget to order quality primer and lacquers from stewmac.com.
PAINTING
YOUR PEDAL
HOUSING
11

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you’re having trouble reading the color bands, there are
apps that make easy working of identifying them. Or, try
using a multimeter to read a resistor’s value. Just set your
multimeter to ohms and connect the test leads on each
side of the resistor.
A number of dierent components are used to make an
eects pedal. Here’s an overview of what they do..
RESISTORS
A resistor is used in an electrical circuit to present an
opposition to current ow. It resists the amount of
current that can pass through it.
A resistor’s value—the amount of resistance it creates—
is rated in ohms (). The higher the ohmic value, the
greater the resistance to this ow of current. For
example, a 100 resistor creates ten times as much
resistance as a 10 resistor.
Resistor values are indicated by colored bands, read from
left to right. The rst color in the code is usually the one
painted closest to a lead. When a gold or silver band is
present, it’s always one of the last colors in the code. If
UNDERSTANDING ELECTRONIC
COMPONENTS
4.7KΩ ±1%
K=1,000
Band 1 Band 2 Band 3 Multiplier Tolerance
4 7 0 x10 ±1% =5-band code:
4-band code: read Bands 1 and 2 same as above, then
Band 3 is the Multiplier and Band 4 is the Tolerance.
BLACK 0 0 0 1
BROWN 1 1 1 10 +/- 1%
RED 2 2 2 100 +/- 2%
ORANGE 3 3 3 1,000
YELLOW 4 4 4 10,000
GREEN 5 5 5 100,000 +/- 0.5%
BLUE 6 6 6 1,000,000 +/- 0.25%
VIOLET 7 7 7 10,000,000 +/- 0.10%
GRAY 8 8 8 100,000,000 +/- 0.05%
WHITE 9 9 9
1,000,000,000
GOLD 0.1 +/- 5%
SILVER 0.01 +/- 10%
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Resistors and capacitors may also be referred to with
shorthand notation on the printed circuit board when
there is a decimal in the value. For example, the place
on the board for the 4.7K resistor will read 4K7 and the
spot for a 2.2nF capacitor will read 2n2. This is done to
save space on the board and make the labels as clear
as possible.
Some capacitors have polarity and some don’t. It’s
extremely important to install polarized caps correctly
in a circuit. The negative lead will often be indicated
by a band of arrows pointing to the negative lead and
will be shorter than the positive lead. The positive lead
of an electrolytic cap will be longer and won’t have
any arrows pointing to it.
Installing capacitors with the polarity backwards will
make the circuit malfunction and quickly destroy the
capacitor— even causing it to explode.
CAPACITORS
The two main uses of capacitors are to store electricity
and to block the ow of DC current.
Capacitor values are typically printed on the
component. The key values with caps are their voltage
and capacitance.
The voltage spec for a cap refers to how much DC
voltage it can handle at any given time. If this rating is
exceeded, the capacitor will fail.
Capacitance, measured in farads, refers to how
much electricity a capacitor can hold. One farad (1F)
would be much too large for use in a pedal. Caps
for pedals are rated between millionths of a farad,
called microfarads (F), billionths of a farad, called
nanofarads (nF), or trillionths of a farad: picofarads
(pF). .001μF = 1nF = 1,000pF.
++
11
1
0
1
J
1
00V
1
02J
1u F
.1J63

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TRANSISTORS
Transistors are used
to amplify electrical
signals. They have
a square tab on
one side. Be sure to
match the tab to the
outlined tab shown
on the circuit board
when installing.
INTEGRATED CIRCUITS
Integrated circuits are
complex, tiny, self-
contained collections
of components that
contain a complete
circuit. Op-amps, audio
processors, and linear
voltage regulators are
three kinds of
integrated circuits.
DIODES
Diodes are used where you want electricity to ow in
only one direction, such as power rectication, and
also to limit how much current can ow, to create
“clipping” distortion.
Diodes are also polarized, so they need to be installed
in the correct orientation. The stripe around one end
marks the negative (minus) lead of the diode. On the
circuit board, the printed outline of the diodes also
shows this stripe. Install each diode so that its stripe
matches the direction shown on the circuit board.
2n2J630
TL072
PT2399
PT2399
PT2399
PT2399
echo audio
processor (1) #7490
TL072CP TL072CP
low noise
op-amp (1) #7444
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POTENTIOMETER
A potentiometer, or pot, is a variable
resistor. This means as the knob shaft
is rotated, the DC resistance
will change. There are three
lugs or soldering terminals on a
conventional potentiometer. The
outside two are the ends of the
resistive strip, and the center lug
is connected to the “sweeper.” The
sweeper allows you to vary the DC
resistance relative to its position along the resistive
strip, or relative to the outer
two lugs.
Potentiometers come in
two varieties, linear-taper
and audio-taper. The linear-
taper pot’s taper works at a 1:1
ratio. Audio taper, has a special
logarithmic ratio.
Audio taper is used because our ears don’t hear
changes in volume in a linear fashion as you might
expect. As the volume increases, a greater change
in signal or sound-pressure is required to perceive a
smooth transition.
LED
LED stands for Light Emitting Diode,
and functionally LEDs are very similar to
regular diodes. LEDs are most often
used as indicator lights in pedals. They
are polarized just like diodes and
electrolytic capacitors and must be
installed in the correct orientation to
work. The positive (anode) lead of the LED
will be longer and the anode side of the
LED housing will be round. The negative
(cathode) lead of the LED will be shorter
and the cathode side of the LED housing
will be at. LEDs are mounted inside
of a bezel, which protects the LED and
insulates the leads from shorting against
the enclosure or any internal components.
13

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The solder joints you’ll make on the circuit boards
are very small, and too much heat can damage the
board. The idea is to make joints quickly, without scorching the holes.
SOLDERING Here’s a few more
soldering tips that
might be helpful:
• Keep your soldering tip
clean by wiping it often on
a damp sponge.
• Also keep it tinned by
occasionally melting a little
solder onto it.
• Don’t blow on the hot
solder or touch anything
until the joint has cooled
completely. A good solder
joint is shiny – a sign that it
was left to cool undisturbed.
• Plan so each joint is only
soldered once. Resoldered
joints are messy and more
likely to fail.
1. Hold components in place for soldering by
threading the leads through the board and bending
them apart on the reverse side. You will be making
your solder joints on the reverse side of the board.
2. Tin the iron by melting a
small amount of solder onto
the tip of the iron.
3. Insert the tip into the hole and let it heat for 4-5
seconds before touching it with solder. This heats the
contact enough for the solder to ow nicely without
damage. Feed the solder to the hole, not the iron, and
you don’t need much solder, just enough to ll the
holet. Keep the iron on the connection for a second
longer; this pause gives time for all of the ux to cook
out of the joint. After the joint has cooled, trim away
the excess lead wire.
14

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1N5817 rectier diode (1)
#7522
BC-108 Transistor (2)
#101123
Insert the diode leads through the component side (the side with the component’s info
silkscreened in white). In many cases, components must be inserted in a specic direction
due to polarity, so follow the graphics carefully. For example, diodes are polarized, so they
must be installed in the correct orientation. Solder the diode and transistors on the opposite
side of the board, known as the solder side.
INSTALL
1 DIODE & 2
TRANSISTORS
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Note the stripe around one end of the diode.
This marks the negative (minus) lead. On
the PCB, the printed outline of the diodes also
shows this stripe. Install each diode to match the
direction shown. Place all diodes with the wires
pointing down, through the component side.

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1K resistor (1) #7357
Brown Black Black Brown Brown
Brown Black Black Orange Brown
100K resistor (1) #7365
Orange Orange Black Red Brown
33K resistor (1) #7409
Yellow Violet Black Brown Brown 4.7K resistor (1) #7359
Yellow Violet Black Black Brown
470Ω resistor (1) #7355
Next, we’re going to add some resisitors to our PCB. Like in the previous step, you’ll nd an
outline of each resistor and its value printed in their proper location on the PCB. Resistors
are not polarized, so it doesn’t matter which lead goes in which hole. Match resistors to the
values on the PCB, a few at a time, and solder in place. Clip the leads close to the board, but
not touching the board so you don’t damage the solder pads.
INSTALL 5
RESISTORS
33

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1µF capacitor (1)
#7337
1uF
47µF capacitor (1)
#7478
47uF
22µF capacitor (1)
#7311
22uF
INSTALL 3
POLARIZED
CAPACITORS
44
The three types of capacitors shown below are polarized and have to be installed in the
correct orientation. Note the stripe running the length of each cap; this identies the
negative (minus) lead. On the circuit board, the circle for this cap’s location has a round
through hole on one side, and a square through hole on the other: insert the capacitors
with their stripe facing the round hole side. (On polarized caps of this type, there’s a
second way to identify the negative lead: it is the shorter of the two leads).

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55
INSTALL 1
CAPACITOR
10nF capacitor (8)
#7331
WIMA
0,01
100-
The remaining capacitor below is not
polarized. However, best practice is to
solder this cap in place with text facing
the bottom of the PCB.
C3
R3
R2R1
R10
R4
D1
CLEAN
BIAS
C3
Q2
C1 C2
C6
Q1
503
502
R1
R10
R4
D1
CLEAN
BIAS
Q2
C1
C2
C6
Q1
50 3
50 2
1K resistor (1) #7357
Brown Black Black Brown Brown
100K resistor (1) #7365 Orange Orange Black Red Brown
33K resistor (1) #7409
Yellow Violet Black Brown Brown 4.7K resistor (1) #7359
Yellow Violet Black Black Brown
470Ω resistor (1) #7355
1N5817 rectier diode (1)
#7522
22µF capacitor (1)
#7311
22uF
1µF capacitor (1)
#7337
1uF
47µF capacitor (1)
#7478
47uF
10nF capacitor (8)
#7331
R3
R2
WIMA
0,01
100-

18
R3
R2R1
R10
R4
D1
CLEAN
BIAS
C3
Q2
C1
C2
C6
Q1
503
502
WD 07
503
502
5K trim pot (1)
#100738
502
50K trim pot (1)
#100739
503
About the trim pots: When you are nished with the build, the two BC108 transistors will need to be
dialed in using these internal adjustable trim pots. One of them is labeled “clean”and the other “bias”.
INSTALL 2
TRIM POTS
66
The internal trim pots featured on the Sun Fuzz allow the user the ne tune the overall
“feel”the pedal will have when engaged. The Clean trim pot adjusts the amount of fuzz
in the signal. The Bias trim pot adjusts the amount of voltage being routed to the transistors.
Both controls have a signicant impact on the sound.
Carefully insert the legs of the trim pots into the
PCB and solder in place on the back of the PCB.
Use a phillips head screwdriver to adjust the high
end frequency. Turn it to the right for more high
end, to the left to remove high end.
CLEAN
BIAS

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StewMac’s PCB Holder (#0500) is perfect for soldering tiny
parts and wires. With two free hands and the ability to
rotate the board, you’ll easily nd the perfect angle to work.
R3
R2R1
R10
R4
D1
CLEAN
BIAS
C3
Q2
C1
C2
C6
Q1
503
502
WD 07
This kit comes with 30" of 22 guage lead wire. Using
the correct 22AWG slot on your wire stripper cut the
wire into eight, 2.5" sections. Strip around 3/32" o
both ends of all wires.
The rst four 2.5” sections will attach the in, out and
DC jacks at the top of the PCB and the other four 2.5”
sections will attach the breakout board to the bottom
center of the PCB.
Insert the stripped ends of the wires into the holes
on the component side of the PCB and solder them
on the back.
77
INSTALL 8
LEAD WIRES

20
WD 08 -2
IN GND SW OUT
R3
R2R1
R10
R4
D1
CLEAN
BIAS
C3
Q2
C1 C2
C6
Q1
503 1E
502 9L
WD 08
Align the PCB and breakout board component side
up. Guide the leads of the 2.5” wires coming from the
bottom of PCB through the holes in the breakout board.
Next, cut two 4” pieces of the remaining 22 gauge
wire and strip 3/32” o both ends of both wires. Insert
one end of each wire into the remaining holes on the
breakout board and tape the leads to the breakout
board on the component side to prevent them from
slipping out of the holes.
Carefully ip the PCB and breakout board over and
solder all the wires in place on the solder side of the
boards. Once the solder has cooled, remove the tape.
SOLDER
BREAKOUT
BOARD TO
THE PCB
88
Now we’re going to attach the
breakout board to the PCB, as
well as attach the wires to the
breakout board that will connect
to the pots. Have a small piece of
masking tape on hand.