Voltage-controlled oscillator
A voltage-controlled oscillator (VCO) is an electronic oscillator whose oscillation frequency is controlled by a voltage input. The applied input voltage determines the instantaneous oscillation frequency. Consequently, a VCO can be used for frequency modulation (FM) or phase modulation (PM) by applying a modulating signal to the control input. A VCO is also an integral part of a phase-locked loop. VCOs are used in synthesizers to generate a waveform whose pitch can be adjusted by a voltage determined by a musical keyboard or other input.
27 MHz VCXO clock generator IC (TLSI T73227), used in a DVB-T set-top box.
The Korg Monologue is a monophonic synthesizer with two VCOs.
An electronic oscillator is an electronic circuit that produces a periodic, oscillating or alternating current (AC) signal, usually a sine wave, square wave or a triangle wave, powered by a direct current (DC) source. Oscillators are found in many electronic devices, such as radio receivers, television sets, radio and television broadcast transmitters, computers, computer peripherals, cellphones, radar, and many other devices.
Crystal oscillator
A 120 MHz oscillator from 1938 using a parallel rod transmission line resonator (Lecher line). Transmission lines are widely used for UHF oscillators.
Image: Ganna gjenerators M31102 1