Snap Circuits 500-in-1 Manual

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Project #381
OBJECTIVE: To construct a time delay circuit.
Turn on the slide switch (S1) and the bulb (L2) does not light. Press
switch (S2) and slowly the bulb lights.
When the press switch is pressed, current flows to the base of the
transistor (Q2) and charges the 100µF capacitor (C4). When the
capacitor charges up to more than 1 volt, the transistor (Q2) turns on
and triggers the SCR (Q3). The bulb will stay lit until the slide switch
is turned off. The values R5 and C4 determine the time it takes until
the transistor turns on. The larger the capacitor value, the more time
it takes to turn on.
Delay Light
Project #382 Project #383
OBJECTIVE: To construct a time delay fan.
Delay Fan
OBJECTIVE: To construct another type of time delay fan.
Delay Fan (II)
Use the circuit in project #381. Replace the lamp (L2) with the motor
(M1) and fan, then replace the 3-snap (base grid locations E6-G6) with
the lamp (L2). Turn on slide switch (S1) and press down the press switch
(S2) to start the motor.
Use the circuit in project #382. Replace the 100µF capacitor (C4) with
the 470µF capacitor (C5). Turn on slide switch (S1) and press switch
(S2). See how long it takes until the motor (M1) spins.
!
WARNING: Moving parts. Do not touch the fan or
motor during operation.