]]Tuning into Satellite TV and Radio[[
To tune in to satellite TV some specific receiving equipment is needed.
The most obvious item is the dish. The dish is the antenna (aerial). It works like a curved mirror to collect, reflect and concentrate the radio energy from the satellite and focusses it into the throat of the
LNB (Low Noise Block).
The
LNB amplifies these very weak signals and converts them to a lower frequency (from about 11GHz down to less than 2GHz), the so-called intermediate frequency. This signal travels along the coaxial cable to the Receiver unit in the home.
The Receiver (often called the set-top box, STB, or Digibox etc) performs all the electronic signal processing that is required to recover the TV signal. In addition it sends power and control signals up the cable to the
LNB. The Receiver is connected to the TV set either by an antenna (aerial / RF) lead or SCART cable. Operation of the receiver and channel selection is normally done with an infra-red remote control unit.
This basic principle of getting the satellite TV signal is the same whether an analogue or digital system is being used. However, the electronic processing of digital and analogue signals is very different indeed.
Digital signals comply with the DVB-S (Digital Video Broadcasting - Satellite) protocol. Look for the DVB logo. For an analogue signal, the signal strength is very important, but for digital reception as much care must be paid to maximizing signal quality (the higher the quality number the less bit-rate errors the receiver will have to cope with).