Hybrid Integrated 10-Watt CW Broad-Band Power Source at S Band

An S-band CW power source consisting of transistor-amplifier-driven varactor-doubler chains fabricated in hybrid integrated form is described. The source employs a microstrip package for high-power transistors, which has good heat sinking and low parasitic reactance and which permits direct paralleling of transistors. A breadboard model of the power source consisting of hybrid integrated components interconnected by coaxial lines produced a CW output of 9.8 watts at 3000 MHz with a 1-dB bandwidth of 6.7 percent and a dc to RF efficiency ranging from 9 to 14.5 percent over the band. The required RF input power to the module was 600 mW centered at 1500 MHz.