FuzzDog Bionic GuzzFun User manual

Bionic GuzzFun
5 knobs of sonic mayhem
and an oscillation switch too
PedalParts.co.uk

Schematic
BO
R1 910K
R2 180K
R3 910K
R4 910K
R5 10K
R6 180K
R7 4 7
R8 910K
R9 750R
C1 100n
C2 10n
C3 470p
C4 4.7u
C5 4.7u
C6 100n
C7 330n
S1-3 SPDT
Q1,2* 2N5089
Q3* 2N5306
DENS 100KB
FUZZ 10KB
FILT 10KB
BIAS 50KB
VOL 100KA
*The stock transistors give highly variable, very gated results, which may not
be to everyone’s taste. That’s all part of the charm of this box. However, if you
want to make it a bit more ‘normal’ you can try subbing some other stuff in
there. 2N5088 work well in Q1-2, and other medium gain NPN cans may offer
good results. A lower gain darlington for Q3 will tame things a bit. PSA13
worked well in reducing the gating, but the legs will need twisting. See later in
the doc for details.
The optional alternatives supplied with the kit are PSA06, which have the
same pinout as 2N5089, and BC517 which is different to the 2N5306 - see over.

Snap the little metal tags off the pots to mount them flush in the box.
You UST use some kind of heat sink on the legs of the transistors
when soldering. They aren’t keen on heat. Any more than 3-4
seconds of iron and they’re toast.
Pots mount on the same side as the components.
Give some thought to placement before soldering in your offboard
wires. Extra pads have been added to make it a doddle. Your 9V and
one GND should be on the same side as the components, as your
DC socket is on that side.
The others should all be on the back side of the board, which will place them very close to
the footswitch.
The two separate GND connections near VOL and BIAS
are for your jack sockets.
Non-standard pinout for Q3 is shown above.
2N5306 come in both ECB and EBC pinouts, so you’ll
need to check yours. If you’re subbing a different can then
you’ll need to check the pinout and twist the legs to fit.
BC517 have this pinout >>>>
Oscillation Switch - you can wire this offboard with any SPDT ON-ON toggle switch. You
can use a DPDT if you want to also wire in a LED to show whether it is engaged or not. You
can even wire it as a separate footswitch (see the Wiring section). Ignore the two holes
above S1-3 - they’re for the dinky board-mount switch which is an option.
OD!
If you want to get super-freaky you can replace R5 with a pot to control how much
oscillation you’ll get when engaged. Just connect pins 1 and 2 of a pot to the resistor pads.
10KB will work, but you may find smaller values and different tapers give a better useable
sweep. Experiment.
1 2 3
E
C
B

Test the board!
Once you’ve finished the circuit it makes sense to test is before
starting on the switch and LED wiring. It’ll cut down
troubleshooting time in the long run. If the circuit works at this
stage, but it doesn’t once you wire up the switch - guess what?
You’ve probably made a mistake with the switch.
Solder some nice, long lengths of wire to the board connections for
9V, G D, I and OUT. Connect I and OUT to the jacks as shown.
Connect all the G Ds together (twist them up and add a small
amount of solder to tack it). Connect the battery + lead to the 9V
wire, same method. Plug in. Go!
If it works, crack on and do your switch wiring. If not... aw man.
At least you know the problem is with the circuit. Find out why, get
it working, THE worry about the switch etc.
BATTERY
IN OUT
Your nice, new circuit board
INCLUDING WIRED POTS!!!!
IN 9V GND OUT

Wire it up - DC only version
There are G D connections for both jacks at either end of the board.
All the G D pads are connected to each other in the traces on the PCB,
and all of them are connected to both sides of the board.
For your convenience there is a G D pad for every required connection.
This circuit is standard, egative G D. Your power supply should be Tip
egative / Sleeve Positive. That’s the same as your standard pedals
(Boss etc), and you can safely daisy-chain your supply to this pedal.
L
E
D
BOARD
OUT
BOARD
9V
BOARD
GND
BOARD
GND
BOARD
GND
BOARD
INPUT
+
IN
OUT
L
E
D
BOARD
GND
BOARD
LED+

Wire it up - with battery
There are G D connections for both jacks at either end of the board.
All the G D pads are connected to each other in the traces on the PCB,
and all of them are connected to both sides of the board.
For your convenience there is a G D pad for every required connection.
This circuit is standard, egative G D. Your power supply should be Tip
egative / Sleeve Positive. That’s the same as your standard pedals
(Boss etc), and you can safely daisy-chain your supply to this pedal.
Just because our pre-drilled
enclosure doesn’t
accommodate a battery, it
doesn’t mean you can’t add
one yourself in a bigger box.
Follow this!
L
E
D
BOARD
OUT
BOARD
9V
BOARD
GND
BOARD
GND
BOARD
GND
BOARD
INPUT
BATTERY
+
IN
OUT
L
E
D
BOARD
GND
BOARD
LED+
+

Oscillation Switch
Maybe you want the oscillation mode on a footswitch...? Wire it as above
and your extra LED will light up when oscillation is engaged.
If you’re using DPDT (footswitch or toggle switch) just pretend that
middle row isn’t there.
You can use a footswitch daughterboard if you want to neatly mount the
LED for the oscillation. Connect the wires as below, but then flip the
PCB so the labels face down onto the footswitch so the LED pads are on
the correct side of the switch. You’ll also have to connect V to 9V and G
to ground to power the LED. Don’t forget the Current Limiting Resistor.
L
E
D
+
L
E
D
S1
S2
S3 GND
9V
S3S1 S2

Drill template - 1590B
Please check positioning before drilling - those holes are your
responsibility and these templates are just a guide.
The best way to mark holes for the pots is to lay the PCB on the box
before you start soldering anything and mark at the centre pad of each.
The DC socket needs to be quite close to the edge of the box so it
comfortably clears the pots.
Recommended drill sizes:
Footswitch, DC 12mm
Jack sockets 9.5-10mm
Pots 7mm (8mm if you’re using the board-mount toggle)
Mini-toggle 5mm
Vertical distance from centre of pots to centre of toggle switch is 19mm.

Drill template - 1590BB
See previous page for notes on sizes etc.
Drill EITHER the second footswitch OR the mini toggle switch,
depending on which you’re using for the oscillation mode.
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