By D. Stevens McVoy, Coaxial Scientific Corporation
Cablenet International Corporation and Coaxial Scientific Corporation·have been operating a per program pay television business in Columbus, Ohio, since June of 1973, using a two-way cable system. This system utilizes technology developed by Coaxial Scientific Corporation which greatly reduces the home terminal cost, simplifies system maintenance, and increases reliability. In the past two years of operation, CSC and Cablenet have gathered a substantial amount of information on two-way system design, construction, balancing, performance, and maintenance. The practical experience gained in the course of operating the two-way CATV system over the last several years will be discussed. An analysis of signal intrusion, noise accumulation, system hum, and system impulse noise problems and their solutions will be among the topics discussed. In addition, day-today operation procedures developed by CSC and Cablenet for two-way systems will be discussed. The experience gained demonstrates that two-way CATV is now economical and practical for not only per program pay television but also other services such as fire, intrusion alarm systems, opinion polling, and interactive data transmission.