By Society of Cable Television Engineers
In the past several years, various proposals have evolved suggesting certain reassignment of television channel frequencies for carriage on a cable T.V. system. Some of these proposals have reached the available hardware stage in head-end equipment. The purpose of the exploration into the reassignment of frequencies is to determine if an arrangement other than the standard FCC broadcast assignments, in conjunction with standard midband and superband assignments, will provide an improvement in the performance of CATV amplifiers, specifically as the output capability of CATV amplifiers manifests itself in terms of second- and third-order beat products.
Three variations to date have been: the constant interval, the harmonically related constant interval, and the pivotal harmonically related constant interval. Each plan may have its own particular advantages and disadvantages and specific location considerations vis-a-vis off-air ambient signal level. In addition, a decision to employ a "non-standard" channeling plan is locked into the terminal equipment decision. The purpose of this panel is to state the pros and cons of the various techniques and relate them to practical applications. The panel represents a cross section of interested parties in this particular area of technology; i.e., receiver manufacturers, headend equipment manufacturers, terminal equipment manufacturers and the cable operator.