The transmission of dual channel sound

The Independent Broadcasting Authority (IBA) is to introduce a Dual Channel Sound (DCS) service on both the ITV and Fourth Channel networks. The major stations will be equipped to transmit DCS to 75% of the UK population by the end of 1990. This will be achieved through replacement of fourteen ITV transmitters with new DCS capable systems and modification of Fourth Channel transmitters at the same sites. The paper describes the modulation principles used in DCS transmission and the distortions which can arise in transmission systems. A DCS test set, developed by the IBA, is described with results of measurements taken in evaluation and modification of Fourth Channel transmitter systems