Project 94
Fan Flash Energy
Place the fan on the motor (M1). Hold down the press switch (S2)
for a few seconds and then watch the color LED (D8) as you
release the switch. The LED flashes briefly but only after the
batteries (B1) are disconnected from the circuit.
Do you know why the LED flashes? It flashes because the motor
uses a magnetic field to spin the shaft. When the switch is released
energy creates a brief current through the LED.
If you reverse the motor direction, then the LED will light the same
way, but the fan may fly off after the LED lights.
Project 95
Fun with the Alarm IC
Phototransistors can be used
to control many devices such
as street lights, clock radio
alarms, night lights, etc.
Place the fan on the motor (M1) and turn on the slide
switch (S1). The lamp (L1) lights, the motor spins,
and you hear a machine gun sound (with very faint
music in background). Cover the phototransistor
(Q4) with your hand and the sound becomes a siren.
After a while the sound will stop, hold down the press
switch (S2) and the sound resumes.
!
WARNING: Moving parts. Do not touch the fan or
motor during operation. Do not lean over the motor.
!
WARNING: Moving parts. Do not touch the fan or
motor during operation. Do not lean over the motor.
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