AMX192 (often referred to simply as AMX) is an analog lighting
communications protocol
A communication protocol is a system of rules that allows two or more entities of a communications system to transmit information via any variation of a physical quantity. The protocol defines the rules, syntax, semantics (computer science), sem ...
used to control
stage lighting
Stage lighting is the craft of lighting as it applies to the production of theater, dance, opera, and other performance arts. . It was developed by Strand Century in the late 1970s. Originally, AMX192 was only capable of controlling 192 discrete channels of lighting. Later, multiple AMX192 streams were supported by some
lighting desks. AMX192 has mostly been replaced in favour of
DMX, and is typically only found in legacy hardware.
History
The name ''AMX192'' is derived from ''analog multiplexing'' and the maximum number of controllable lighting channels (192). AMX was developed to address a significant problems in controlling
dimmer
A dimmer is a device connected to a light fixture and used to lower the brightness of the Lighting, light. By changing the voltage waveform applied to the lamp, it is possible to lower the Luminous intensity, intensity of the light output. Al ...
s. For many years, in order to send a control signal from a lighting control unit to the dimmer units, the only method available was to provide a dedicated wire from the control unit to each dimmer (analogue control) where the voltage present on the wire was varied by the control unit to set the output level of the dimmer. In the late 1970s, the AMX192 serial analogue
multiplexing
In telecommunications and computer networking, multiplexing (sometimes contracted to muxing) is a method by which multiple analog or digital signals are combined into one signal over a shared medium. The aim is to share a scarce resourceā ...
standard was developed in the US, permitting one cable to control several dimmers.
At about the same time,
D54 was developed in the United Kingdom, and differed from AMX192 in that it used an embedded clocking scheme. AMX192 used a separate differential clock with a driver circuit similar to
RS-485
RS-485, also known as TIA-485(-A) or EIA-485, is a standard, originally introduced in 1983, defining the electrical characteristics of drivers and receivers for use in serial communications systems. Electrical signaling is balanced, and Telecomm ...
, but current limited on each leg with 100Ī©
resistor
A resistor is a passive two-terminal electronic component that implements electrical resistance as a circuit element. In electronic circuits, resistors are used to reduce current flow, adjust signal levels, to divide voltages, bias active e ...
s.
See also
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Dimmer
A dimmer is a device connected to a light fixture and used to lower the brightness of the Lighting, light. By changing the voltage waveform applied to the lamp, it is possible to lower the Luminous intensity, intensity of the light output. Al ...
*
Lighting control console
A lighting control console (also called a lightboard, lighting board, or lighting desk) is an electronic device used in theatrical lighting designer, lighting design to control multiple stage lighting, stage lights at once. They are used throughou ...
*
Lighting control system
A lighting control system is intelligent network-based lighting control that incorporates communication between various system inputs and outputs related to lighting control with the use of one or more central computing devices. Lighting control ...
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DMX512
DMX512 is a technical standard, standard for digital communication networks that are commonly used to control lighting and effects. It was originally intended as a standardized method for controlling stage lighting dimmers, which, prior to D ...
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RDM
External links
Strand Lighting CorporateUniversity of Exeter - Strand Archive
Stage lighting
Network protocols
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