Session Synopses

The adoption of the NTSC color television system about 20 years ago added the entire new dimension of color to the television signal without any increase in required bandwidth. Although of considerably smaller scope, many ingenious techniques have been developed for the insertion of ancillary communications within the television signal. Within the active video portion of the signal such techniques have provided for an emergency channel for the sound portion of the signal. Employing portions of the horizontal blanking interval, high quality audio channels can be provided using pulse amplitude, pulse code or pulse width modulation techniques. Within the audio portion of the television signal many systems have been developed which involve unobtrusive audio tones for alerting station personnel, for the automatic control of equipment and for program or commercial identification. Several systems are also under consideration which involve tones designed for alerting the general public in times of a national emergency.

Print ISSN
Published
1971-11
Content type
Original Research
DOI
10.5594/J05711