[en] A 150-kV, 80-A power supply and neutral beam test facility is now operational at the Lawrence Berkeley Laboratory, Berkeley, California. This supply uses banks of 450-V electrolytic capacitors for over 10⁶ joules of energy storage. SCR switches control the power flow to the neutral beam accelerator. Turn on and off times of a few microseconds are possible. An auxiliary capacitor bank also uses SCR switches to provide regulation (''flat-topping'') of the main bank output by switching in additional capacitors as the main bank discharges. Air-operated switches are used to connect the main-bank sections in parallel for charging and series or parallel for discharge, depending on the operating voltage desired. A single digital switch sets the desired operating voltage. Filament and arc power supplies are also solid state. With the exception of the suppressor supply which has one vacuum tube the complete neutral beam system uses all solid state components