have imagined (Figure 13). It is fascinating how — even
though you are aware that each skeleton is operating in a
non-programmed random fashion — it seems as if they
move to and with a musical background. They even seem
to synchronize with each other, having motions that are at
first complimentary and then in counterpoint to each
other. To get the full effect, I highly suggest having a look
at the video (link in the Resources section) of the finished
trio performing to an original sound track by Marvin
himself. He’s not only an artist, he’s a
After you’ve built your own
dancing skeletons or ghosts or
spiders or whatever prop you’ve
decided to animate, keep in mind the
concept of Apophenia. This tendency
of humans to find patterns in random
motions could be very useful in
other projects — artistic or not.
As examples, the random movements of a robot
could be perceived as intentional, or random LED lighting
patterns could be viewed as meaningful. There are lots of
ways you can use this knowledge to your advantage in all
sorts of human interface designs.
If you do come up with a project that takes advantage
of this phenomena, please let me know! You can reach
me via email at email@example.com. NV
Order Toll Free 1-800-826-5432
2.5mm stereo phone plug,
standard on most cordless home
phones. However, most current cell
phones / smart phones require a 3.5mm
plug. Use adapter CAT# AD- 25.
CAT# PHN- 39
Reduced Price! $2.35 $150 each 100 for $1.00 each
Great stereo sound
This 20W per
channel amplifier was
designed for use in a portable outdoor music system.
There are no external controls; volume is
controlled from an MP3 player, cellphone or
other audio source. A button on the front
panel mutes the sound. Heavy-duty metal
cabinet, 9. 5" x 8. 5" x 2".
CAT# AMP- 15
KEYSWITCH, 4PST ON-OFF
Two-position keyswitch. 5A 250 Vac.
Key removable in
one position only.
switches, 2-on and 2-off
in each position. New switches. Two of the
four poles are prepped with four 4" Teflon-insulated leads. Two keys. UL, CSA, CE.
CAT# KSW- 32
24VDC 3A POWER SUPPLY
6' output cord with
2.5mm coax plug,
center negative. Includes
cord. cULus, CE.
$1100 each 10 for $10.00 each
Miniature photovoltaic cell in a 5mm diameter LED-type package. 0.53 Vdc.
CAT# PD- 8 $100 for 2 100 for 40¢ each
CONTROL, 12VDC 6 AMP
Ideal for automotive
applications, but can also
be adapted to home use
with the addition of a 12 Volt
relay. Switches 12 Vdc
loads up to 6 Amps.
Operates on small 12V
alkaline batteries VR22 /
CN22 / CN23A (our CAT# BAT- 27). Includes
two keychain transmitters with batteries and
CAT# RC- 10
4-Channel remote, see CAT# RC- 13, $38.00
DOOR LOCK ACTUATOR
12 Vdc motor-drive
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Nylon plunger moves
0.75". Push or pull, depending on polarity.
Includes mounting hardware and a 9. 5" extension rod. Actuator assembly (retracted):
5. 50" x 2. 45" x 1.25". Rubber boot for moisture and dust protection.
Pigtail leads. CAT# DLA-1
A Note on Power
If you don’t happen to have suitable power
supplies in your junk box, I would
recommend picking up a multiple-voltage
power supply from a surplus electronics
vendor. For example, All Electronics has
the PX- 17. This is multiple voltage power
supply with selectable voltages of
3/4.2/5/6/7/8.4 VDC at a maximum current
from 1.7A 8.4V to 2.5A 3V.
It includes short-circuit protection
and automatic overload cut-off,
and is listed for under $10.
Some other suitable offerings are available
from suppliers such as Marlin P. Jones ...
... and from Electronic Goldmine
Of course, if you want some precise speed
control, you could always opt for a PWM
based speed control kit such as this one
offered by Ramsey Electronics ...
... or this one from QKITS
Lastly, if you don't plan to run your display
for extended periods, you could always
power these systems on batteries. The
Tamiya gearbox should run well on two AA
batteries, whereas the larger gearhead
motors might need a bit more current. So,
four C or D cell batteries might be in order.
September 2014 59