User Manual

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Project #83
OBJECTIVE: To show some new ways of using the alarm IC.
Build the circuit shown and place the fan on the motor (M1), but leave the
jumpers off for the time being. Turn on the slide switch (S1) and tap the whistle
chip (WC), it makes a machine gun sound (with music in the background).
Thoroughly cover the photoresistor (RP) with your hand and the sound
becomes a siren. With the photoresistor covered, press the press switch (S2)
and the sound becomes that of an ambulance. Uncover the photoresistor and
the sound remains that of a machine gun whether the press switch is pressed
or not. After a while the sound will stop, tap the whistle chip and it resumes.
Connect the two jumpers as shown and tap the whistle chip to resume the
sound. The lamp (L1) and LED (D1) light and the motor spins. The sound
continues, but it may become distorted as the motor speeds up. The motor
draws a lot of power from the batteries (B1), and this may reduce the voltage
to the music (U1) and alarm (U2) ICs, distorting the sound. The sound may
even stop if your batteries are weak.
Fun with the Alarm IC
Project #84
OBJECTIVE: To connect multiple devices
together.
!
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.
Project #85 Motor
Sounds
Combo (II)
OBJECTIVE: To connect multiple devices
together.
In the circuit, the outputs from the
alarm and music ICs are
connected together. Build the
circuit shown and then place the
alarm IC (U2) directly over the
music IC (U1), resting on three 1-
snaps. Turn on the slide switch
(S1) and you will hear a siren and
music together. Push the press
switch (S2) and the fan spins, while
the sound may not be as loud. The
fan may rise into the air when you
release the switch.
This circuit is similar to project #84,
but the fan will fly a little higher
since the sound circuit no longer
drives the lamp (L1) and therefore
uses less battery power.
!
WARNING: Moving parts. Do not touch the fan or
motor during operation. Do not lean over the motor.
To learn more about how circuits work, visit www.snapcircuits.net or page 45 to find out about our Student Guides.
Motor
Sounds
Combo
In the circuit, the outputs from
the alarm and music ICs are
connected together. Build the
circuit shown and then place
the alarm IC (U2) directly over
the music IC (U1), resting on
two 1-snaps and a 2-snap.
Turn on the slide switch (S1)
and you will hear a siren and
music together while the lamp
(L1) varies in brightness. Push
the press switch (S2) and the
fan spins, while the sound may
not be as loud. The fan may
rise into the air when you
release the press switch.