■ FIGURE 1.
Enclosure is Jameco #18922
2. 5 mm high-brightness Live Wire draws about 8 MA/meter at 80 volts and 1KHz
offer a huge range of devices, the programming tools are
cheap, and they seem well-suited to this task. Going back
to my prototype board, I programmed a PIC12F675 to
switch one of the pins on and off, fed the signal to the
G3VM- 2, and the EL wire blinked at my command!
Now, I had to design the controller. The shirt I had
used with the simple inverter was an Eric Clapton concert
T-shirt from many years ago (see Photo 1). Even when it
was just a simple blinking guitar outline, it was popular at
concerts. What could I do to improve it?
There was just enough room on the neck of the guitar
to allow four wires across. The body of the guitar was
another circuit, for a total of five circuits. The PIC12F675
has six I/O pins. If I reserved one for a switch to change
the pattern, I’d have five output pins. That left just
connecting the controller to the shirt. Looking around my
parts bins, I spotted a spare Ethernet cable. Hmmm, eight
wires. I checked the specs for the connectors, and they
are rated for 120 volts AC at 1.5 amps. Five control lines,
two grounds, and a spare. Perfect!
I now had all of my major components selected, so I
started on the schematic (see Figure 1). I used
ExpressSCH from ExpressPCB (
assigned each pin on the connector to a circuit. I assigned
the spare pin to an “always on” circuit. Each of the
controllable circuits led back to a G3 switch (U2-U7; note
that I numbered them to match the pin they are attached
to), then to the PIC pin. The pattern-changing switch is
connected to pin 4 through a 1K ohm resistor. The pin is
pulled high through R9 (10K) until you press the switch.
Printed Circuit Board
I designed the printed circuit board (PCB) to fit into a
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