tip: Seal the eyes with slightly heated five minute epoxy
using a disposable paint brush. Heat the epoxy with a
heat gun or hair dryer (carefully) to make it flow smoothly.
Practice first! Too much heat will bubble the coating. Also
be aware that heating the epoxy makes it set up a little
quicker, so work fast. You’ll have shiny, wet-looking
eyeballs in less than five minutes! The 24 mm irises can be
found at etsy.com.
The enclosure/book itself could be made by cutting
out the center of the pages of an old dictionary and gluing
them together, but that’s a lot of work. It’s faster to buy a
book box — a box that looks and opens like a book. One
such box is made by Punch Studio and their medium size
is just right — about 8-1/2 x 11 x 2-1/2” (Figure 6).
Magnets hold the cover shut, but you don’t want that.
Find them with a single-edged razor blade, cut them free,
and completely remove them. (The magnets are tiny, so
keep them away from small children.) The cover should
SERVO 10.2014 55
FIGURE 3. Populated prop board.
FIGURE 4. Top component placement.
Prop Board Parts List
1 Four-channel TX/RX IC2272 315 MHz
1 V module, VMA2012 three-watt stereo
1 MP3 player Tenda TDB380
1 Printed circuit board (see text)
1 SD memory card 2 GB or less
1 9V relay SPST OJE-SS-109LMF, OEG-SDT-SS-109DM, or equivalent;
they are different sizes, but the PCB will accomodate both.
1 PIC16F690 Microchip IC
2 Mini PCB pushbuttons, 6 mm
5 N-channel FET, NTD4963N-35G or equivalent
2 Break-apart 40-pin pin headers, .1" (or 2. 54 mm pitch)
1 Proper charger for lithium-ion batteries
2 Eight ohm speakers 2", at least 5W each
1 Battery power connector, matched to battery connector
1 7805 5V 1A regulator IC or equivalent
1 7806 6V 1A regulator
2 10K resistors
1 100 ohm resistor
1 3 or 5 mm LED, any color
1 1N4148 diode
3 1N4003 diode
1 Schottky diode 1N5817
2.1 µf ceramic capacitors
1 Lithium-ion 11.1V battery 1,000 mAh or larger
3 220 µf 16V radial electrolytic capacitors