Operation of the TEMPO machine

The TEMPO machine is a repetitively pulsed, high-voltage driver for experimental microwave generating devices. Three units have been built. TEMPO has a transformer-charged, water-insulated Blumlein directly coupled to the vacuum diode. The Blumlein has a relatively high impedance (20-..cap omega..) strip-type, pulse-forming transmission line (PFL) designed to minimize size. Stray capacitance and enhanced electric fields along the edges of the PFL are controlled by lining the tank in which the Blumlein is housed with polyvinyl chloride (PVC) plastic sheet. During the initial stage of operation, problems with breakdowns in the plastic occurred that necessitated replacing the liner with either polyethylene or polypropylene. During the same period, problems with the power supplies and high voltage switch performance were addressed. These modifications and their results are discussed in the following sections.