A Precision Dc Potentiometer Microwave Insertion Loss Test Set

A simple, accurate microwave test set has been devised for measuring coaxial or waveguide insertion loss. The instrument is designed primarily for highest precision with low attenuations. It is composed almost entirely of commercially available equipment and components, is portable, and can be operated in the laboratory or in the field from ac mains or batteries. The precision of the measurements depends on the connector type and value of the component measured. The precision is better than 0.0001 dB when measuring low insertion losses, discounting the error due to the connectors. Equipment nonlinearity reduces the precision in proportion to the measured attenuation in dB. The frequency range covered is 10 MHz to 40 GHz, which can be extended to 90 GHz with slight perfornance degradation.