Manual

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V
CO? What’s that? VCO stands for voltage
controlled oscillator, and as the name implies, this
o
scillator changes its oscillation frequency
according to the voltage applied to the circuit. The
circuit creates two different output signals that have
triangular and square waves.
When you finish the wiring sequence, slide the
switch to position A to turn on the power. Turn the
control slowly while you listen to the sound from the
earphone. The sound becomes lower when you turn
the control clockwise.
Turning the control changes the voltage at terminal
27, which changes the 0.01mF capacitor’s charging
and discharging times, which changes the oscillator
frequency. The output signal from the first
operational amplifier is a triangular wave signal is at
terminal 67, and is applied to terminal 65 of the
second amplifier. The second amplifier acts as a
comparator, and produces a square wave signal at
terminal 64.
N
otes:
EXPERIMENT #96: VCO
Wiring Sequence:
o 79-63-26-131
o 27-87-89
o 46-91
o 47-76
o 86-92-109-64
o 65-78
o 66-80-83-85
o 67-102-77
o 68-90-101-75
o 69-88-81
o 84-70-134
o 121-135
o 122-132
o 124-119-28-48-94-82-14-EARPHONE
o 110-93-13-EARPHONE
Schematic
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