A Novel TV Add-On Data Communication System

This paper presents a description of the theory and operation of a new television add-on data communication system which does not utilize the vertical interval. The basic add-on signalling technique allows more efficient utilization of the television spectrum. Added information, producing no perceptible interference with either the picture, or ancillary and test signals, is sent through a television channel along with the standard video signal. Novel techniques to significantly reduce errors in the data channel will be described. Several interesting systems utilizing this new signalling method have been built and will be described in this paper.