Abbreviation for via net loss.

Abbreviation for voice-coder. A device that usually consists of a speech analyzer, which converts analog speech waveforms into narrowband digital signals, and a speech synthesizer, which converts the digital signals into artificial speech sounds.
Note 1: For COMSEC purposes, a vocoder may be used in conjunction with a key generator and a modulator-demodulator to transmit digitally encrypted speech signals over… (Read More →)

Video on Demand

Acronym for voice-operated device anti-sing. A device used to prevent overall voice-frequency singing in a two-way telephone circuit by ensuring that transmission can occur in only one direction at any given instant.

Acronym for voice-operated gain-adjusting device. A device that has a substantially constant output amplitude over a wide range of input amplitudes.

Synonym voice frequency.

See vocoder.

A UIH (unnumbered information with header check) frame that contains a voice packet in its information field. [T1.312-1991]

Pertaining to those frequencies within that part of the audio range that is used for the transmission of speech.
Note 1: In telephony, the usable voice-frequency band ranges from approximately 300 Hz to 3400 Hz.
Note 2: In telephony, the bandwidth allocated for a single voice-frequency transmission channel is usually 4 kHz, including guard bands. Synonym voice band. See electromagnetic… (Read More →)

A patching facility that provides the first appearance of local-user VF circuits in the technical control facility (TCF).
Note: The VF primary patch bay provides patching, monitoring, and testing for all VF circuits. Signals will have various levels and signaling schemes depending on the user terminal equipment.