Build the circuit board
- Use tin snips or a hacksaw to cut your perfboard to size. The usual shape for
a project of this type is a horizontal rectangle. This rectangle must fit your
case. Typical boards are about two and a half to three inches high by three or
four inches long. Allow plenty of room
for your parts, plus a little extra for miscalculation and mounting. Cramped
layouts aren't a good idea. But do make sure that the PC board will fit your
case. You don't want to have to trim the board after mounting the parts. (If
you must, you can. Still, the chance of snapping off leads is very real.)
- With bus wire, mount your ground and Vcc lines. Take your roll of naked steel bus
wire and turn loose several inches of wire. Don't cut it. Run the end of the wire
through the second-to-the end hole in the board. Let about one and a half inches
extend beyond the board. Run the spool side of the wire across the back of the board.
Insert the wire into the second-to-the-end hole in the board. Let another inch and a
half length of wire extend beyond the board. Then cut the wire at this point. Now loop
both extending pieces of wire back though the board in the outside holes. Double the
wire back to the second hole and allow about a a quarter inch of overlap. Then twist
the wire on the top of the board into a loop. The two loops are great for connecting
test power with alligator clips.
- With an indelible marker (Sharpie® or similar), mark the board near each bus wire:
On both sides of the board and in several places, mark a "+" for the Vcc bus and a "-"
for the ground bus.
- Use your schematic as a template for parts placement as well as for wiring.
- Following your schematic, mount the first transistor to the board. Leave at least a
half inch between the left edge of the board and the transistor base. In the vertical
direction, the transistor should be about in the middle of the board. The collector
lead should be nearest to the Vcc bus. The emitter lead should be nearest to the
ground bus. Collector and emitter should mount in holes in line with one another.
The base should mount between these other two leads. The base should be one hole to
the left of the other two leads.
Build the case
- Buy a cast aluminum case. Sheet aluminum isn't heavy enough to take the
abuse. Cast aluminum is easy to work. Avoid steel cases. They're hard to work, and wear down
your tools quickly. Don't be stingy. Get a case with plenty of room for parts. A long case
allows you to stomp the switch without smashing the controls. If the case has
enough room, you can also mount the battery on the outside. Outside mounting
offers the advantage that curious fingers don't ever get inside the project.
- Lay parts on the top of the case. Try to figure out the best layout. Leave plenty
of room between controls for wiring. Keep the stomp switch well away from the
other controls and cables. Otherwise, your fuzzbox won't last long. Allow room
under or over the controls for labels.
- For reference, draw out the layout in exact size. Do the drawing in pencil. Then
you can revise it.
- Drill the case for the controls and jacks.
- If you used a second-hand case, putty up the extra holes.
- Paint the case. For a few days, let it dry.
- Label the case. Use mylar printable film. (I printed my label on the laser printer.)
- Mount your ground bus and Vcc bus to the back of the perfboard. I suggest
that you label both buses. Just mark a "+" and a "-" on the board in a few places.
Use an indelible, lacquer marker.
- Mount the battery clip, controls and jacks to the case.
- Solder the parts into the circuit.
- On the PC board, mount studs for chassis-mount controls, etc.
- To provide strain relief, knot the battery line inside the case.
- In the case, mount the board, controls and jacks.
- Solder stranded, insulated wires between the board and off-board
parts: 2-Pots, 1-Switch, 1-Battery clip (case exterior), 2-Jacks. Solder
with mounted parts in the case. Leave just a little slack in your wires.
Allow that little extra wire that will allow opening the case. Make parts access
and servicing as easy as possible. To replace a pot, you shouldn't need to cut
all the wires.
- Before you close the case, insert a folded copy of the schematic. Better still,
mount the schematic inside the case. Make sure that the diagram is easy to read.
Test the effect
- Connect the battery.
- Check the board for shorts and opens.
- With a guitar and amplifier, perform music tests. If you don't have a
guitar handy, you could also test the fuzzbox with a microphone. I tried the
microphone test. When I talked into the mic, I became fuzzy. Success!
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