The 3680 series Universal Test Fixture (UTF) provides an accurate, and repeatable solution for measuring microstrip and Coplanar substrate devices. Input and output connections are made to the substrate device by two spring-loaded jaws that include coax-to-microstrip/Coplanar launchers. The jaws accommodate substrates from 0.13 to 1.9 mm in thickness. No center section is required. One jaw is movable in two dimensions to accommodate substrates up to 50 mm long (100 mm for 3680-20) and substrates with line offsets of up to 12.7 mm (25 mm for 3680-20). The 3680 series UTF includes three models: the 3680-20 covering DC to 20 GHz with APC-3.5 TM connectors, the 3680K covering DC to 40 GHz with Anritsu's K Connector®, and the 3680V covering DC to 60 GHz with Anritsu's V Connector®.