Abstract: A microwave oscillator arrangement comprising a microstrip resonator, a Gunn oscillator mounted outside the substrate of the resonator, a varactor diode connected in series with the Gunn oscillator and the resonator, and means for applying adjustable bias to the varactor diode.

Abstract: A dielectric waveguide oscillator includes a microwave producing diode, a strip resonator, and a dielectric waveguide butted against one end of the strip resonator.

Abstract: A frequency tunable microwave apparatus including a semiconductor TRAPATT diode generating a microwave signal at its fundamental, second and third harmonic frequencies. Energy is extracted at the second harmonic frequency and a certain impedance loading is provided at the fundamental frequency and third harmonic by a variable impedance hybrid idler circuit. The hybrid idler circuit comprises a distributed transmission line serially connected to a lumped variable capacitor. Variations in the capacitance of the variable capacitor tune the fundamental frequency without substantially varying the impedance loading conditions of the diode allowing energy to be extracted at the second harmonic frequency throughout the tunable frequency range.

Abstract: A varactor tuning apparatus for tuning a strip transmission line radio frequency device, wherein the device having predetermined operating characteristics includes an active element such as an avalanche diode and a resonant conductive strip section. The tuning apparatus comprises a separate varactor circuit having a varactor mounted on a dielectric substrate including a resonant conductive strip. The varactor circuit is RF coupled to the strip transmission line of the device to provide for tuning the device by varying the reactance of the strip transmission line by electrically changing the capacitance of the varactor.

Abstract: A two-inductor varactor tunable solid-state microwave oscillator comprising a series tunable circuit wherein one inductor is serially connected with a negative resistance active element, an impedance load, and a varactor. The circuit is tuned by changing the reactance of the circuit by varying electrically the capacitance of the varactor. The second inductor is connected in parallel with the varactor to increase the range of reactance change of the series circuit effected by the variation in capacitance of the varactor to provide thereby for a wider frequency tuning range.