The 85021A Directional Bridge is designed especially for the 8757A, 8756A and 8755C Scalar Network Analyzers. The unit features outstanding directivity and test port match in a compact, rugged package. Within the unit, one zero-bias Schottky diode detector measures the return loss of the test device. The unit covers the 10MHz to 18GHz frequency range. It uses a Type-N Female input connector and a APC-7 output connector.