• Satellite dish"Dish and Sky" is Copyrighted by Flickr user: cogdogblog (Alan Levine) under the Creative Commons Attribution license.
  
  

Function

• Satellite receiver communication can be conducted on either low- or high-band channels. The amount of power surging through the coaxial cable determines the exact protocol used. If less than 15 volts is going up the dish cable, the LNB (Low Noise Blocker) detects only vertically polarized transmission. On the other hand, if more than 15 volts are used, the LNB detects only horizontally polarized transmissions. The LNB then relays the appropriate signal to the satellite receiver.
  
  DiSEqC helps control the LNBs, enabling them to switch back and forth between the low- and high-band channels as needed. DiSEqc messages are sent in short bursts of a 22 kHz tone. The signals consist of eight-bit digital bytes, with the sequence of numerals, either 1s or 0s, commanding the proper component operation. DiSEQc enables one switching box to run numerous LNBs, increasing efficiency and performance.
  
  

Features

• DiSEqC operates on the standard 22 kHz tone generator associated with upper and lower band switching. This allows it to squeeze more channels into a given frequency, because it can transmit channels with either vertical or horizontal polarization. DiSEqC's versatility and low cost has made it the industry standard for satellite receiver-component communication.
  
  

Benefits

• DiSEqC can replace existing communication protocols, whether analog or digital, in all commercial satellite installations. The chief benefit of DiSEqC is it provides a standardized digital system for channel switching without any proprietary commands or restrictions. It also enables switching in multisatellite installations.
  
  

History

• Eutelsat, a European satellite provider, developed DiSEqC as an open standard, making it available to the public. In 1977, Eutelsat began as an intergovernmental organization designed to build satellite infrastructure across Europe. It launched its first satellite in 1983 and quickly became one of the industry leaders in Fixed Satellite Services. Eutelsat has extended its reach beyond Europe, conducting business in the Americas, Africa, Asia and the Middle East.
  
  

Misconceptions

• Although its name may indicate otherwise, Digital Satellite Equipment Control can be used on more than just digital systems. DiSEqc can operate analog or only partially digital systems, as well.