See Chapter 4 for more information about choosing drill bit sizes for par-
ticular components and other advice 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 potentiometer through the drilled hole and secure
with the nut provided. - Slip the knob on the potentiometer shaft and secure with the set screw.
- Slip the threads of the headphone jack through the drilled hole and
secure with the nut provided. - Slip the threads of the audio jacks through the drilled holes and
secure with the (you guessed it) nuts provided. - Slip 8-32 screws through holes in the clamp and the holes you drilled
in the box and secure with nuts from the inside of the box. - Solder the black wire from the battery pack to one lug of the on/off
switch and solder an 8" black wire to the remaining lug of the on/off
switch, as shown in Figure 6-17. - Solder one 8" black wire to the lug on one of the audio jacks and
solder one 8" red wire to the lug on the other audio jack, as shown
Figure 6-17. - Solder 8" wires to each of the three potentiometer lugs, as shown in
Figure 6-17. - Solder one 8" black wire and one 8" red wire to the lugs of the head-
phone jack, as shown Figure 6-17.
The red wire should go to the contact that touches the tip of the head-
phone plug.
Okay, we’ll say it again: Heed all the safety precautions about soldering that we
give you in Chapter 2. Don’t ever leave your soldering iron on and unattended.
And to avoid damage from flying pieces of solder, wear your safety glasses!
Chapter 6: Focusing Sound with a Parabolic Microphone 133