Elenco Snap Circuits SOUND &reg - Manual (Page 56)

Project 92 Oscillator
This circuit is an oscillator, because it
produces a repetitive electrical signal on its
own. You hear it as sound waves from the
speaker. The signal is produced by a circuit
inside the keyboard module, but may be
controlled using your Snap Circuits®
resistors and capacitors, and the keys on
the keyboard. The keys are actually
connecting different resistors inside the
keyboard, similar to the 5.1k
W resistor (R3).
Project 93
Oscillator (II)
Project 94
Oscillator (III)
Project 95
Oscillator (IV)
Project 96
Oscillator (V)
Use the preceding circuit, but
replace the 1
m F capacitor (C7) with
the 0.1 m F capacitor (C2). Do you
hear anything? The circuit is
producing a high frequency tone,
which may be too high for your ears
to hear, especially if you are older.
Now remove the 0.1 m F capacitor
from the circuit. This makes the
tone even higher frequency, and
you probably won’t hear anything
now. Dogs have better high
frequency hearing, so maybe your
dog can hear it.
Use the preceding circuit, but replace
the 5.1k
W resistor (R3) with the 100 W
resistor (R1). The frequency of the
sound is higher now, and you hear
several clicks a second.
Use the preceding circuit, but replace
the 470
m F capacitor (C5) with the 1 m F
capacitor (C7). The frequency of the
sound is much higher now, and you hear
a continuous tone.
Use the preceding circuit, but replace
the 1
m F capacitor (C7) with the 470 m F
capacitor (C5). The frequency of the
sound is now so low that you just hear
a click every few seconds.
Use the preceding circuit, but replace
the 0.1
m F capacitor (C2) with the 1 m F
capacitor (C7). The frequency (pitch)
of the sound is lower now.
Build the circuit, and turn the slide switch
(S1). You hear a tone. You can also press
keys on the keyboard (U26) to change the
sound.
Project 98
Left Right Bright Light
Turn on the slide switch
(S1) and move the
lever on the adjustable
resistor (RV) around.
The color LED (D8) is
bright if the lever is to
the far left or far right,
and dim if the lever is in
the middle.
Project 97
Oscillator (VI)
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