The High Voltage Assembly ITA (HVA ITA) is a Traveling Wave Tube (TWT) Power Supply. It provides the high voltage cathode voltage and grid pulse signals necessary to operate a TWT during test. The HVA ITA provides control and monitoring circuitry for TWT Unit Under Test and fully simulates the radar system environment. The HVA ITA is available as a fully integrated element of a Test Program Set or as a stand-alone test adapter for integration by the end-user. The HVA ITA can be produced for a variety of bias voltage ranges, duty cycles, pulse repetition frequencies, and pulse widths.