Mechanical aspects and component features of a new 12-channel open-wire carrier system

A NEW line of carrier equipment known as the class 45 has been developed with a view toward application on open-wire lines, paired and coaxial cable, and radio systems. Both mechanical and electrical design have been co-ordinated for each of the systems in these respective applications. In this paper, the 45A system arrangements for open-wire use are described. In basic terminal equipment, no differences exist for the various applications. Substitution of a small number of common group-modulating assemblies, modifications in slight degree in carrier supply, and rearrangements of terminal frame assemblies identify specific uses. Great stress has been placed on standardization in this respect, both to speed the development in the different areas of ultimate use and also to increase the demand for specific items of manufacture. With the major part of this equipment alike among these different systems, and differences introduced by the relatively small number of group-identifying parts, it has been possible to come out almost simultaneously with manufactured terminal arrangements for most of the fields of application. Transmission features and electric performance of the equipment are described in a companion paper by Appert, Caruthers, and Chaskin.1