Emergency Standby Facilities for the Aural Television Transmitter

This paper presents a simple method for using the visual carrier of a television broadcast station for the purposes of transmitting both the aural and visual signals. The method is intended for use during emergency operation when the sound portion of the TV transmitter is ``off the air'' and the visual portion of the transmitter is in working order. This system is not recommended as a substitute for a standby transmitter. While various methods of transmitting the sound on the picture carrier are known, a simple and economical method of multiplexing is desirable for a TV broadcasting station. Consideration was given to a system which would require no adjustment of the main visual transmitter should the normal sound transmitter fail. The signal to noise ratio of the multiplexing system to be described is not as favorable as the conventional method of transmission.