Test Equipment for the TH Radio System

It became apparent early in the development program for the TH radio system that to operate the system in the field and to attain its high performance objectives would require the regular use of accurate field test equipment. Therefore, the planning and development of field maintenance facilities was done concurrently and cooperatively with, and continued throughout, the development of the rest of the TH system. At the outset it was decided to include in a mobile console all of the test instruments required to make all routine and some trouble location tests on each major subdivision of the system. From this philosophy, there results a number of mobile test consoles, each named for that portion of the system which it is primarily designed to maintain. Transmitter-receiver test sets, available in all repeater stations and maintenance centers, are designed to assure optimum performance of the broadband radio transmitter and receiver and the RF and IF portions of the auxiliary channel. 1 KM terminal test sets, available wherever there arc FM terminals and in maintenance centers, are designed to adjust and maintain FM terminal transmitters and receivers.2 Protection switching test sets, appearing at all switching stations, maintain the protection switching system. 3 Currently under development is an auxiliary channel test set for testing baseband portions of the auxiliary channel. 1717