■ FIGURE 5. The inside of the frame.
are available on the Nuts & Volts website (click
“Magazine” and then “Downloads” and find “Shazam”).
You will need to download the free software from
www.expresspcb.com to view the schematic and the PCB
(printed circuit board). (However, I think you will find it
cheaper to order the boards from the Nuts & Volts store.)
Also available is a
pre-programmed
PIC16F690 if you
don’t want to
program it yourself.
If you don’t have
a PIC 2 programmer
and still want to
program, put a 20-pin
socket in IC1 and
solder. Note that the
square pin is pin 1 on
both ICs. Solder IC2,
the resistors, and
capacitors into their
proper areas. I put an
extra pad in for C1 so
that you can use
either 2. 5 mm or 3
mm radial capacitors.
Note the “+-” on the
220 µF and 4. 7 µF
caps. Solder in the
three male headers at
SPK, the mic, S2, the
five male headers in
the programming
■ FIGURE 7. The back of the frame.
pads, and the three-position female
headers in the PIR
area. If using a three
D, three C, or three
AA battery pack,
thread the wire
through the strain
relief hole and
solder the red lead
to the + and the
black to the -. (All
chips will run on 4. 5
volts.) You can also
use a five volt
battery eliminator.
Do not use four
batteries as the PIR
will lock up!
If programming
with a PIC 2, make
sure you place the
DIP switches in the
open position. The
chip can also be programmed by other programmers if it’s
removed from the board. The assembly files are also on
the N&V website.
■ FIGURE 6. Inside the frame showing the flash.
Display
The display I built is rather unique. I made a
transparency of the picture drawn by Charles Allan Gilbert
called “All is Vanity.” It is a picture of a woman sitting in
front of her mirror and vanity. However, when viewed
farther back, it becomes a skull. The picture is available on
the N&V website if you want to use it.
The frame I used was the cheapest 8” x 11” stand-up
frame I could find. The back was removed. I tacked the
transparency on each corner to the glass using super glue.
A sheet of white tissue paper was tacked to the
transparency on each corner giving a semi transparent
background but still showing off the picture. I took the
back and added a 3/8” x 1” pine strip to make it look like
a shadow box mount and painted the outside with a flat
black paint. The inside was left unpainted. Holes were
drilled in a zig-zag pattern with a #60 drill for the LEDs.
The Superbrite LEDs were pushed through the back and
held with wire wrap. The circuit board was mounted on
the inside of the box in the left lower corner using 1/4”
standoffs and 6-32 screws. However, I found that the PIR
would not detect through either the transparency or the
glass. I ended up drilling a 7/8” hole through the bottom
of the picture frame and inserted the PIR into this hole
from the inside, then tacked it with hot glue. I used a 3-pin
male header and plugged it into the PIR female header,
then wire-wrapped the PIR using the wire as an extension.
There are mounting holes in the board, and the 1/2“
34
October 2010