A milliwattmeter for the 70-80 Gc/s frequency band

The considerations leading to the design of a milliwattmeter for use at 75Gc/s are outlined and the design is described. The incident power is dissipated in a load and the temperature rise measured by a thermopile giving a sensitivity of 36 ¿V/mW. The device is calibrated by passing a measured current through the load. The input v.s.w.r. over the band 70¿80 Gc/s is greater than 0.7.