Abstract: A broad band, balanced microwave component, such as an amplifier, includes an input Lange coupler having a first center frequency and an output Lange coupler having a second center frequency. The center frequencies of the two Lange couplers are offset or the coupling is different so that at least one of the cross-over points of the input Lange coupler is offset in frequency from both the cross-over points of the output Lange coupler. The pair of Lange couplers so offset in frequency yields no more than one peak in gain which is readily equalized by single-ended amplifiers within the balanced amplifier.

Abstract: A tunable coupled transmission line band reject filter for use in the microwave frequency range includes a coupled transmission line having first and second line sections. Each line section has an input end and an output end. A transmission line exhibits a natural notch at a particular frequency. A first varactor is coupled between the input ends of the first and second sections. A second varactor is coupled between the output ends of the first and second sections. A D.C. bias voltage across the varactor diodes controls the center frequency of the resulting notch filter.

Abstract: Recirculation is prolonged in a broadband microwave loop by flattening the overall frequency response of the loop. A bandpass filter, tuned to the input signal frequency, is placed in the loop after the broadband amplifier. A frequency discriminator responsive to the input signal controls the filter driver.

Abstract: Spaced conductive strips are formed on a substrate. A first transmission line transformer is connected between the input and one end of the first strip. A second transmission line transformer is connected between the other end of the first strip and the output. The second strip is connected to ground. A shunt tuning circuit is connected between the strips. The circuit includes first and second MOS capacitors mounted on and connected to the grounded strip. An RF choke interconnects the other side of each capacitor. A varactor diode is mounted on and connected to the first capacitor. An etched spiral inductor connects the varactor and the first strip. A bias signal is applied to the junction between the choke and the second capacitor in order to tune the filter.