Eleven-centimeter broadband correlation radiometer

A broadband hybrid-junction radiometer operating at 2700 MHz is described. It employs twin receiving channels, each with two-stage synchronously pumped degenerate paramps, and has an overall effective bandwidth of 200 MHz. Installed on the 210-ft radio telescope at Parkes, New South Wales, it gives a system noise temperature of
80\deg
K and an rms recorder fluctuation of
0.006\deg
K for a 2-second smoothing time constant.