Free Circuit Diagram

This circuit is a simple crystal oscillator that can be operated in overtone mode. Overtone mode permit the operation at higher frequency than specified by the crystal. The circuit uses a grounded base amplifier configuration, and place the crystal as a series resonator. The transistor Q1 is biased in the active region as [...]

Quadrature oscillator generate two sine-wave signal, but one signal is shifted 90 degree from the other signal. One output that lead the other called cosine signal, and the other is called sine. Here is the schematic diagram of the circuit: This circuit is another type of pahase shift oscillator, with three phase shifter [...]

Bubba oscillator is another example of phase shift oscillator. The Bubba oscillator takes the advantage of quad op-amp package to get 45 degree phase shift for each section. The result is excellent d(phase)/d(t) to get very low frequency drift. Here is the schematic diagram of the circuit: Each RC section give 45 degree [...]

With very low harmonic distortion, 2N4416 JFET is suitable to smoothly oscillate in a circuit. On application where low harmonic content is required for a good mixer circuit, JFET local oscillator is very good. Below is the circuit diagram of Low Distortion Oscillator: And here’s the 20 MHz Oscillator Values [...]

Sawtooth wave oscillator is used in cathode ray tube deflection circuitry, in a PWM modulator, or in a analog to digital conversion. You can also use it in your own design, only your imagination can limit its application. Here is one example of the circuit: The frequency is determined by C1, R1, R2, [...]

Crystal Colpitts oscillator can be implemented using a transistor and a parallel mode crystal. Here is the schematic diagram of  the circuit: In this circuit, the crystal acts as an inductance. A large value capacitive divider is used between gate, source, and ground, and a small series capacitor is placed in the crystal [...]