Free Simple Circuit Diagram
VCO (voltage controlled oscillator) is an electronic signal generator which produce a signal that has variable frequency depends on a voltage level at its control input. Many VCO circuits are based on ramp generator to produce a variable frequency output, but they produce a square wave signal. With varactor (voltage controlled variable capacitor), we can produce a high quality sine […]
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This is a Wien-bridge sine-wave oscillator circuit. This circuit uses negative-feedback stabilization to make sure the gain won’t go higher than unity to prevent signal distortion. The D2 and D1 will conduct when Negative peaks in excess of -8.5 V. That action will charges C4. The amplifier gain is determined by the biased Q1 that is charged by C4. Offset […]
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This is a 100MHz Varicap Oscillator circuit. This circuit can provide modulation signals less than 28V and frequency deviation of 28 MHz peak-to-peak. This circuit uses two variable-capacitance diodes which is connected to d-c bias and audio modulating signals in parallel connection and connected in series to r-f. Here is the circuit: [Circuit’s schematic diagram source: seekic.com]
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Phase shift oscillators uses capacitors to shift the phase of a signal coming from the output of an amplifier. If the phase shifting match the frequency, then a positive feedback will be produced a continuous sine waveform. Here is the basic schematic diagram of the circuit: To maintain the oscillation, the gain of the amplifier should produce exactly same amplitude […]
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