Voltage Controlled Oscillator for Commercial FM Band

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 […]

Read more

100MHz Varicap Oscillator

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]

Read more

Basic Phase Shift Oscillator 1KHz

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 […]

Read more
1 2 3