Microwave Radio Equipment and Building Considerations

Microwave radio relay stations have existed in the Bell System in several forms since 1950.1 In this time, the equipment and the layouts within the buildings have changed to accommodate the new designs that have been introduced into these systems. The introduction of the T D - 3 repeater bay offers further opportunities for improvements particularly in the simplification of power requirements. The basic power for a T D - 3 station is --24 volts dc. Those power plant elements peculiar to TD-2, namely the +250, + 130, and --12V dc plants have been eliminated. Voltages other than --24V dc are furnished by dc-to-dc converters, except for +24V dc which may be furnished by a separate plant in some stations. Except for the power plant, the typical T D - 3 station will not differ greatly from recently constructed TD-2 stations, since the 100A IF protection switching system, 2 the 3A FM terminals, and the 3A solid-state wire line entrance links have been previously introduced into the TD-2 system. The 200A protection switching system for use with the 3A FM terminals and wire line entrance links has been developed for long haul microwave radio systems.