(1) (Voltage Controlled Oscillator) An oscillator that can be tuned over a wide range of frequencies by applying a voltage (tuning voltage) to it. Used in many applications such as radio tuners, VCOs are less costly than crystal oscillators, but not as stable. Contrast with crystal oscillator.
An offering of Telecommunications Relay Service (TRS) that allows a person with a hearing disability to use his or her own voice to speak directly to the called party, but receive responses in text from the communications assistant (CA), who acts as a facilitator. See also TRS.