The AR6A Single-Sideband Microwave Radio System: Terminal multiplex equipment

A combination of new multiplex facilities provides the 6000-message-circuit loading for AR6A radio. It includes a Mastergroup Translator Type-B (MGTB) arrangement that accepts five U600 mastergroups to translate and combine them into a Multimastergroup (MMG) spectrum. A new multimastergroup translator for radio accepts two such MMG spectra from MGTB to produce the intermediate frequency signal and pilots for the AR6A line. A pair of pilots from the Bell System reference frequency transmission unit may be added to the MMG spectrum to be recovered at the receiving end for office synchronization. An office master frequency supply sends synchronization frequencies accurate to within one part in 10
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for the MGTB and Multimastergroup Translator-Radio translating equipment. Description, design features, and performance characteristics are described in detail below.