Low Phase Noise, 125 MHz Crystal Oscillator

Jfet pierce crystal oscillator

The JFET Pierce crystal oscillator allows a wide frequency range of crystals to be used without circuit modification

Crystal checker

This circuit is a simple Pierce oscillator with an LED go/no go display

Collection of Crystal Oscillators

On following pages circuits are shown for 3rd overtone crystals 15 to 65MHz and 5th overtone crystals 60 to 105 MHz operating in their series resonant mode. In both of these circuits with the crystal short circuited, the oscillator should operate at or near the required frequency. With the...

Crystal Oscillator Circuit

The CMOS amplifier is biased into the linear region by resistor RB. The pi-type crystal network (CI and C2, and XTAL) provides the 180 phase shift at the resonant frequency

Fundamental-frequency-crystal-oscillator

For frequencies below 20 MHz, a fundamental-frequency crystal can be used and the resonant tank is no longer required. Also, at this lower frequency range the typical MECL 10,000 propagation delay of 2 ns becomes small compared to the period of oscillation, and it becomes necessary to use a...

Crystal-controlled oscillator

This circuit oscillates without the crystal. With the crystal in the circuit, the frequency will be that of the crystal

One-Chip Crystal-Controlled Converter Circuit

This circuit can work over a wide range of frequencies. XTAL 1 is a fundamental-frequency crystal. Tl and CI are tuned to the input frequency. An application of this circuit is a simple shortwave converter for AM radios, etc.

Overtone crystal oscillator

The crystal element in this circuit is connected directly between the base and ground. Capacitor Cl is used to improve the feedback due to the internal capacitances of the transistor. This capacitor should be mounted as close as possible to the case of the transistor. The LC tank circuit in the...