Additional sound channels on PAL television transmissions

This paper describes work performed for an Electronic Engineering final year undergraduate project. Several different systems were investigated for the incorporation of additional sound channels on a PAL television transmission system. The pilot tone system similar to that employed in FM stereo radio was found to be the most suitable and a prototype system providing two additional audio channels was designed and constructed. The proposed system is fully compatible with existing TV transmissions, whilst ensuring sound quality equal to that of the existing audio channel. The prototype was tested on a commercial television set where signal-to-noise ratios, total harmonic distortion and crosstalk were measured.