implement the usual switching/override business.
So, What’s Possible With It?
The convoluted wiring of Figure 1 may have
left you scratching your head a bit. Just to make
sure you understand what all is possible as you
customize things for your own setup, let me tell
you how I flip the switches in my rig. Recall that S1
is the output switch, while S2 is the microphone
switch. You might want to peek ahead to Figure 2
which shows what the front panel looks like. On
that, you can see the switch labels for each of the
three positions which are:
S1 — Output:
• Line: The sound card output is routed to either
J1/J2 (cassette deck) or J10/J11 (guitar amplifier).
• Phones: The sound card output is routed to
headphones; S2 determines if these are headphones
connected to J7 or J14, or the earpiece in a headset
connected to J5.
• Spkr: The sound card output is routed to the PC
■ FIGURE 3.
S2 — Microphone:
• Headset: The microphone in the headset is used at J8,
and the sound card output is routed to the earpiece in
the headset at J5.
• Mute: No microphone is connected, but any
headphones or speakers selected continue to work as
• Computer: The monitor-mounted microphone is
selected at J9, and the headphones at either J7 or J14
are used (not the headset).
Warm Up the Iron
Of course, your arrangement may turn out differently
from mine depending on the gear you expect to hook up.
To let you in on the possibilities, here’s how I built my
sound card switcher.
You’ll want to start by gathering all of the
components. The Parts List shows the items I used, but
your shopping list will probably be a little different to
cover your requirements. In any event, none of the parts
are particularly hard to come by. For example, Jameco
and All Electronics (both advertisers in this magazine)
have a very wide selection of switches, plugs, and jacks
sure to match what you need for your rendition.
By the way, I was able to find everything I required
in my electronics junk box and so didn’t have to spend
I housed the entire thing in a plastic project box
rescued from the trash, believe it or not. The front cover is
aluminum and secured in place with four small machine
bolts. The dimensions weigh in at 6 x 3-1/2 x 2 inches.
This appears to be a standard size (at least the cover plate
is), so you could probably employ the front panel design
shown in Figure 2 without change. What I did was print
the pattern out on a light blue card stock, laminate it with
clear sticky-back film, and glue the entire label to the
aluminum panel with rubber cement. You could follow
suit, if desired, simply by photocopying Figure 2 on some
card stock of your own choosing. By the way, the figure
also serves as the drilling guide; the crosshairs show
where to aim the drill bits.
July 2012 45