Elenco Circuit Maker Sound Plus 200 - Manual (Page 54)

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Project #120 Tone Generator
Project #121
Tone
Generator (II)
Place the 0.1mF capacitor (C2) on
top of the whistle chip (WC) in the
preceding circuit, you hear a
lower-frequency sound. Why?
The whistle chip is used here as
a capacitor and by placing the
0.1mF on top (in parallel) we have
increased the capacitance, and
doing so lowers the frequency.
Project #122
Tone
Generator (III)
Now replace the 0.1mF (C2) with
the much larger 10mF capacitor
(C3), (orient with the positive (+)
side towards the left); the circuit just
clicks about once a second. There
isn’t a constant tone anymore due
to other transistor properties. You
need a different type of circuit to
create very low frequency tones.
Project #123 More Tone Generator
Place the 0.1mF capacitor (C2) on
top of the whistle chip (WC). The
sound is different now because
the added capacitance has
lowered the frequency. The LED
appear to be on, but are actually
blinking at a very fast rate.
Now place the 10mF capacitor
(C3, “+” side up) on top of the
whistle chip (WC). You hear a
clicking sound as the LEDs blink
about once a second.
Build the circuit and turn it on; you hear a high-frequency sound
Project #124
More Tone
Generator (II)
Project #125
More Tone
Generator (III)
Build the circuit; as the name suggests, this circuit is similar to that in
Project #120. Turn it on; you hear a middle-frequency sound.
CM-200_Manual_031914.qxp_CM-200_Manual_031914 4/2/14 12:04 PM Page 54