S-PARAMETER MEASUREMENTS OF HIGH-TEMPERATURE SUPERCONDUCTING AND NORMAL CONDUCTING MICROWAVE CIRCUITS AT CRYOGENIC TEMPERATURES

A fixture is presented that accepts both nounal and superconducting mi crostrip structures for S-parameter measurements. The use of small rep laceable inserts and a compression contact for the strip makes the fix ture especially suited for rapid prototype testing of microstrip circu its. The technique is explained and measurements at room temperature a nd at low temperatures are demonstrated.