Microwave-frequency synthetisers

A new type of microwave-frequency synthetiser, suitable for use in digitally tuned u.h.f. and microwave superheterodyne receivers (and possibly also signal generators), is described. The method is based on phase locking a voltage-tuned transistor oscillator to successive harmonics of a fundamental crystal oscillator, resulting in an all solid-state design capable of operation up to Xband. Early experimental work on a u.h.f. synthetiser is noted, and basic functional diagrams are provided.