Elenco Electronics EP-130, Руководство пользователя

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VCO? What’s that? VCO stands for voltage
controlled oscillator, and as the name implies, this
oscillator changes its oscillation frequency
according to the voltage applied to the circuit. The
circuit produces two different output signals that
have triangular and square waves.
When you complete 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. When you turn the control clockwise, the
sound becomes lower.
When the voltage through terminal 27 of the control
changes, the 0.01
μ
F capacitor’s charging /
discharging time also changes, causing a change in
the frequency of the oscillator. Current that shows a
triangular wave travels from terminal 67 of the first
operational amplifier to terminal 65 of the second
amplifier which acts as a comparator. The
comparator releases output from terminal 64 -
current that shows a square wave.
Notes:
EXPERIMENT #81: VOLTAGE CONTROLLED OSCILLATOR CIRCUIT
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
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Schematic