The uosatmma and u.h.f. data beacons and antenna system

single canted turnstile antenna is used for satellite transmission and command reception in the v.h.f. and f. bands. Details of the antenna hybrid and coupling filters are given, together with performance measurements. The v.h.f. and u.h.f. beacons use 5th overtone oscillators 72 MHz, and a multistage varactor modulator provides sufficient phase modulation with overall frequency multiplication of only x 2 at v.h.f. and x 6 at u.h.f. Some unusual aspects of the design and construction are described.