In electronics, a distribution amplifier or simply distribution amp, is a device that accepts a single input signal and provides this same signal to multiple isolated outputs.

These devices are important because they allow a signal to be distributed to multiple destinations without ground loops

Ground loop (electricity)

In an electrical system, a ground loop usually refers to a current, almost always unwanted, in a conductor connecting two points that are supposed to be at the same potential, often ground, but are actually at different potentials. Ground loops created by improperly designed or improperly installed...

 or signal degradation. They are used for a number of common engineering tasks, including multiple amplification, cable television

Cable television

Cable television is a system of providing television programs to consumers via radio frequency signals transmitted to televisions through coaxial cables or digital light pulses through fixed optical fibers located on the subscriber's property, much like the over-the-air method used in traditional...

, splitting monitor and front of house

Front of House

Front of house is primarily a theatrical term, referring to the portion of the building that is open to the public. In theatre and live music venues, it typically refers to the auditorium and foyer, as opposed to the stage and backstage areas...

 mixes, and "tapping" a signal prior to sending it through effects units to preserve a "dry" signal for later experimentation.

Video distribution amplifier

A Video Distribution Amplifier (also known as a distribution amp or VDA) is a type of electronic equipment that takes a video signal as an input, amplifies it, and outputs the amplified video signal to two or more outputs. It is primarily used to supply a single video signal to multiple pieces of video equipment.

Function

Video signals can suffer deterioration over relatively short cable distances. To compensate for that loss, a Video Distribution Amplifier (VDA) is used.

A VDA adjusts the amplitude

Amplitude

Amplitude is the magnitude of change in the oscillating variable with each oscillation within an oscillating system. For example, sound waves in air are oscillations in atmospheric pressure and their amplitudes are proportional to the change in pressure during one oscillation...

 of a video signal to compensate for loss of signal in a video distribution system. Extending the distance of the signal of the video signal is the main purpose of the VDA.

There are VDAs built for all video formats, NTSC

NTSC

NTSC, named for the National Television System Committee, is the analog television system that is used in most of North America, most of South America , Burma, South Korea, Taiwan, Japan, the Philippines, and some Pacific island nations and territories .Most countries using the NTSC standard, as...

, ATSC

ATSC

ATSC standards are a set of standards developed by the Advanced Television Systems Committee for digital television transmission over terrestrial, cable, and satellite networks....

, QAM16, QAM32, QAM64, Composite Video

Composite video

Composite video is the format of an analog television signal before it is combined with a sound signal and modulated onto an RF carrier. In contrast to component video it contains all required video information, including colors in a single line-level signal...

 and Component Video

Component video

Component video is a video signal that has been split into two or more component channels. In popular use, it refers to a type of component analog video information that is transmitted or stored as three separate signals...

.

Their construction and capabilities can be simple; accept input signal, amplify, then output. Others can be more sophisticated that allow remote control from a control station, allow adjustment of the gain, equalization, and provide status of the input and output signals through Ethernet networks.

External links

• Info about some very common distribution amplifier types.