Elenco Upgrade Kit SC100 to SC750 - Manual (Page 14)

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Project #118
OBJECTIVE: To show how to make electricity in one direction.
When building the circuit, be sure to position the motor (M1) with the
positive (+) side snapped to the 470
μF capacitor (C5). Turn on the
slide switch (S1), nothing will happen. It is a motor speed detector,
and the motor isn’t moving. Watch the LED (D2) and give the motor a
good spin CLOCKWISE with your fingers (don’t use the fan blade); you
should see a flash of light. The faster you spin the motor, the brighter
the flash will be. As a game, see who can make the brightest flash.
Now try spinning the motor in the opposite direction (counter-
clockwise) and see how bright the flash is — it won’t flash at all
because the electricity it produces, flows in the wrong direction and
won’t activate the diode. Flip the motor around (positive (+) side
snapped to the 3-snap wire) and try again. Now the LED lights only if
you spin the motor counter-clockwise.
Motor Speed Detector
Project #119
OBJECTIVE: To show how a generator works.
Turn on the slide switch (S1), nothing will happen. Turn the motor (M1)
slowly with your fingers (don’t use the fan blade), you will hear a
clicking that sounds like an old-time manual typewriter keystrokes.
Spin the motor faster and the clicking speeds up accordingly.
This circuit works the same if you spin the motor in either direction
(unlike the Motor Speed Detector project).
By spinning the motor with your fingers, the physical effort you exert is
converted into electricity. In electric power plants, steam is used to
spin large motors like this, and the electricity produced is used to run
everything in your town.
Old-Style Typewriter