High tension (H.T.) supply 0-300V (DC) adjustable for anode voltage, independent variable knobs are provided for L.T. & H.T. adjustment. (Milliamperes) filament voltage in (Volts), plate voltage in (Volts) & plate current in (Milliamperes). provided on the front panel. The whole system is enclosed in metal cabinet. Kit is used to determine the work function of cathode material.