Device and construction refinements yield first 33 to 50 GHz GaAs FET YTO

It is announced that limited production of a 33 to 50-GHz gallium-arsenide, field-effect-transistor, yttrium-iron-garnet-tuned fundamental output oscillator has begun. It is the first wideband signal source to compete effectively with backward-wave oscillator tubes and oscillator-multiplier chains as a local oscillator or swept signal source in this frequency range. The oscillator, designated AV-33050, combines a GaAs FET fundamental oscillator with three stages of single-ended GaAs FET amplification, followed by a balanced amplifier stage to provide a minimum +7 dBm output power with a maximum plus or minus 3 dB output variation over the full tuning range. The unit will be available integrated with analog (voltage/current) and digital drivers, for tuning with a 0 to 10 V analog signal or 12-bit TTL digital word. It operates from low dc voltages and provides good tuning linearity, moderate efficiency and an extremely compact package. The 5-mW power level of the present version suits it for backward-wave oscillator replacement in many instrument and electronic warfare receiver applications. Single sideband phase noise will be in the range of -80 to -90 dBc/Hz at 20 kHz from the carrier. Specifications of the 19-oz device over the 0-65 C operating case temperature range are tabulated.