The Model B-12 Regulated Power Supply is a reliable source of d-c voltage, bias voltage, and filament power. The B-12 is a most valuable device for testing and developing any new circuit you may build. The B-12 is also useful for testing during normal servicing of electronic instruments. The power supply offers regulated d-c voltages from 0 to +400 volts, and from 0 to -150 volts. Each output is variable throughout its range, with a front panel control. The 0 to +400 volt, d-c supply voltage and current are monitored with a voltmeter and milliam- meter, both mounted on the front panel for easy viewing. The voltage of the 0 to 150 volt bias supply is also monitored. Filament voltages of 6.3 volts a-c center tapped, 6.3 volts a-c (no center tap), and 12.6 volts a-c are available at terminals on the front of the unit, as are the d-c bias voltages.