audio subcarrier

In TV transmission via satellite, several subchannels are provided for sound transmission, which can be used for stereo sound but also for multilingual transmissions, for commentary sound or audio film versions for the blind. This means that internationally broadcast TV programs can be backed up with country-specific commentaries or films can be broadcast in the local language.

Frequencies above the video signal are available for the audio subcarriers, always at intervals of 18 MHz, starting at 7.02 MHz. In total, the transponders offer 8 audio subcarriers, which could be used in pairs for stereo sound at 7.02 MHz and 7.20 MHz, 7.38 MHz and 7.56 MHz, 7.74 MHz and 7.92 MHz, and 8.10 MHz and 8.28 MHz. In addition, some telecommunications satellites still provide audio subcarriers at 6.12 MHz, 6.30 MHz, 6.48 MHz, 6.66 MHz and 6.84 MHz.