DiSEqC (an abbreviation for Digital Satellite Equipment Control) is a specialized switch operating according to a specific protocol that allows transmitting signals from different LNBs via a single cable. The LNBs can receive different satellites and may even be installed on different antennas. When a certain channel is selected, the DiSEqC switch activates the required LNB.
The DiSEqC protocol is a specialized communication protocol that enables data exchange between a satellite receiver and other peripheral devices such as switches, polarizers, and positioners. This protocol uses a coaxial cable for signal transmission and can operate in either one-way or two-way mode, including the ability to transmit power. The DiSEqC standard is compatible with traditional 13/18-volt voltage switching and a 22 kHz carrier frequency. In addition, the term "DiSEqC" is often used to refer to the switches themselves that support this protocol.
The DiSEqC protocol is used to control various peripherals in satellite TV reception systems, including positioners, switches, and even LNBs. DiSEqC commands are transmitted via the cable, providing both power and control to devices using 22 kHz tone signals with a defined amplitude. The protocol employs pulse-width modulation to transmit data, where the pulse width determines the transmitted bit.
The DiSEqC standard has several levels, each defining a set of commands and device capabilities. It also provides for both unidirectional and bidirectional communication between the receiver and peripheral devices. Variations of the standard include DiSEqC 1.0, 1.1, 1.2, 2.0, and 2.1, each offering different functionalities such as switching between LNBs or controlling a positioner.
Although mentioned in the standard, the DiSEqC 3.0 level has not yet been implemented in the market and lacks a concrete description. This level is expected to provide two-way communication between receivers and peripheral devices, which could be useful in collective systems. However, in practice, devices supporting DiSEqC 3.0 are not available.
Some variations of DiSEqC, such as 1.3, may be used by manufacturers and retailers to designate other protocols, but such types have no official confirmation from "Eutelsat".