Elenco Circuit Maker Sound Plus 200 - Manual (Page 57)

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Project #132 Buzzing in
the Dark
Project #134
High Frequency
Touch Buzzer
Now place the lamp (L4) across the points
marked A & B (in parallel with the speaker,
SP2). Now touching your fingers between A1 &
C1 creates a higher frequency sound.
Project #135
High Frequency
Water Buzzer
Now connect two (2) jumper wires to points A1
& C1 (that you were touching with your fingers)
and place the loose ends into a cup of water.
The sound will not be much different now,
because your body is mostly water and so the
circuit resistance has not changed much.
Project #136
Mosquito
Place the photoresistor (RP) into the circuit in
Project #135 across where you were
connecting the jumpers (points A1 & C1 on the
grid, and as shown in Project #132). Now the
buzz sounds like a mosquito.
Project #133
Touch Buzzer
Remove the photoresistor (RP) from the
preceding circuit and instead touch your fingers
across where it used to be (points A1 and C1
on the base grid) to hear a cute buzzing sound.
This circuit makes a high-
frequency screaming sound
when light shines on the
photoresistor (RP), and makes a
buzzing sound when you shield
the photoresistor.
Project #137
Loud Mosquito
Now place the 10mF capacitor (C3, “+” side up)
across the points marked C & D (in parallel with
the 0.1mF capacitor, C2). Now the sound is
much louder.
The circuit works because of the resistance in
your body. If you put back the photoresistor
and partially cover it, you should be able to
make the same resistance your body did, and
get the same sound.
CM-200_Manual_031914.qxp_CM-200_Manual_031914 4/2/14 12:04 PM Page 57