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Project #296, Light oscillator project #297, Sound, light & motor stepper circuit – Elenco Electronics 202 User Manual

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Project #296

OBJECTIVE: To control an oscillator circuit using light.

Set the adjustable resistor (RV) to the middle position and then turn on
the slide switch (S1). Wave your hand over the photoresistor (RP) and
the sound changes. You can adjust the sensitivity by moving the
adjustable resistor to a different position.

Light Oscillator

Project #297

OBJECTIVE: To build a stepper circuit that powers a motor,
speaker and LED.

Set the adjustable resistor (RV) to the far left and turn on the slide
switch (S1). The circuit produces around two pulses per second,
which power the motor (M1), speaker (SP) and LED (D1). Increase
the rate by moving the adjustable resistor to the left.

Change the 10

μF capacitor (C3) to the 100μF(C4) and see how the

time changes.

Sound, Light & Motor

Stepper Circuit

!

WARNING:

Moving parts. Do not touch the fan or

motor during operation.