The current market for fast switching frequency sythesizers is growing rapidly. Most synthesizers available today will not meet the stringent requirements for switching quickly, providing spectrally pure RF outputs and minimizing physical size and cost. As part of a current SBIR program, S.T. Research has developed a wideband, fast switching synthesizer, based on the use of broadband phase-locked loops (PLLs) and direct RF generation. This synthesis technique produces coherent outputs of exceptional spectral purity, and can switch and settle over the full .5-18.5 GHz range in under 300 nsec. The proposed SBIR program will miniaturize this demonstrated technology using the latest micro-wave monolithic integrated circuit (MMIC) parts and technology to produce a wideband,fast-switching, spectrally pure synthesizer of minimal size weight, and power consumption. Mass production techniques will be considered allowing the unit to be mass produced for a fraction of the cost of currently available synthesizer units. The performance features of this synthesizer design in conjunction with the lowered size, weight, and cost of this proposed unit result in efficient, cost-effective government and commercial microwave systems requiring stability, low phase noise, and fast switching speed. Examples of such systems include: Satellite and terrestrial communications, both fixed and mobile. Airborne and man-portable tactical systems such as electronic warfare intercepept and signal analysis systems, ECM jamming set-on receivers, LPI phase-coherent radars, active missle seeker systems. Portable test sets for EW and radar systemes used in both tactical and laboratory environments. Commercial and academic RF test and measurment equipment.