Elenco Projects 306-511 - Manual (Page 57)

-56-
Project #489
Set the meter (M2) to the LOW (or 10mA) setting. Instead of driving a
speaker (SP) with the music IC (U1), you can see it by using the meter.
Turn on the slide switch (S1) and the meter deflects according to the
rhythm of music. After the music stops, hold down the press switch
(S2) to make it continue.
Hand-control Meter
OBJECTIVE: To understand music deflection.
OBJECTIVE: To control the circuit using
light.
Use the circuit in project #489. Replace the
press switch (S2) with the photoresistor (RP).
The music IC (U1) outputs a signal, as long as
a light is present on the photoresistor. The
photoresistor is like a short, connecting the
pin to the battery. When the song repeats,
cover the photoresistor with your hand, the
resistance goes up, and the music stops.
Light-control
Meter
Project #490
OBJECTIVE: To start the circuit using an
electric motor.
Electric-
control Meter
Project #491
OBJECTIVE: To start the circuit by using the
whistle chip.
Sound-control
Meter
Project #492
Use the circuit in project #489. Place the
motor (M1) across points A & B. Turn on the
slide switch (S1) and the meter (M2) deflects
and swings according to the rhythm of music.
When deflection stops, rotate motor to start
the music again. The voltage generated by
the motor triggers the IC again.
Use the circuit in project #489. Place the
whistle chip (WC) across points A & B. Turn
on the slide switch (S1) and the meter (M2)
deflects and swings according to the rhythm of
music. When deflection stops, clap your
hands next to the whistle chip, the music plays
again. The clapping sound vibrates the plates
in the whistle chip, creating the voltage
needed to trigger the IC.