ABSTRACT
Many analogue camera/recorders have the facility of recording four audio tracks. Often two of these tracks are recorded on the longitudinal tracks and two tracks are encoded as an audio frequency modulation (AFM) signal and are recorded in the same area of the tape as the video information. These tracks can only be recorded at the same time as the pictures. They are designated as tracks 3 and 4 and are of superior quality to the conventional longitudinal tracks, 1 and 2.
