- Drill holes in the box where you will insert the microphone and on/off
switch.
We put both the potentiometers and on/off switch on one side of the box
and the microphone on another side, but the placement is really up to
you. Chose a drill bit size for the microphone hole so that the micro-
phone has a slip fit. The upcoming Figure 5-22 shows where we place
these components.
See Chapter 4 for more information about choosing drill bit sizes for par-
ticular components and other pieces of wisdom on how to customize a
box for your projects. Make sure you use safety glasses when drilling,
and clamp the box to your worktable!- Slip the shaft of the on/off switch through the drilled hole and secure
with the nut provided. - Slip the shaft of the potentiometers through the drilled holes and
secure with the nuts provided. - Slip a knob over the shaft of each potentiometer and tighten the knob
with the set screw provided.
The tread on potentiometers is about^1 ⁄ 4 " long, so if the wall of your
wooden box is^1 ⁄ 4 " thick, you won’t be able to use the nut to secure the
potentiometer. Instead, check to make sure that the potentiometer shaft
extends far enough beyond the box to allow the knob set screw to tighten
on the shaft. If the shaft extends far enough, glue the face of the poten-
tiometer to the box, making sure that you don’t get any glue on the rotat-
ing shaft of the potentiometer. If the shaft doesn’t protrude quite enough,
use a small chisel to remove some wood on the inside of the box to let
the potentiometer shaft extend a little farther before you glue.- Slip the microphone into its drilled hole with a press fit.
Figure 5-22 shows the on/off switch, potentiometers, and microphone in
place in the box.- Solder 12" black wires to each of the three potentiometer lugs, as
shown Figure 5-23. - Solder the black wire from the battery pack to one lug of the on/off
switch and solder a 12" black wire to the remaining lug of the on/off
switch.
Figure 5-23 shows the switch after the wires are soldered. - Attach Velcro to the breadboard and the box and then secure the
breadboard in the box. - Attach Velcro to the battery pack and the box and then secure the bat-
tery pack in the box.
Chapter 5: Making Light Dance to the Music 109