Abstract
A solid-state Doppler Radar outdoor equipment has been designed and developed which can serve as an ideal replacement for existing outdoor equipments using vacuum tubes throughout for generating microwave power, for amplifying audio frequency Doppler signals and other applications. The performance of the equipment has been evaluated in—10°C to +80°C ambient temperature range and found to be quite satisfactory. The equipment has also been installed in a railway marshalling yard, and is working satisfactorily as speed sensor in an automatic closed-loop retarder control system.