To produce high voltage alternating current or pulses of high voltage current from a low voltage direct current source. Suitable for use with gas-filled discharge tubes, vacuum tubes, eudiometers and for general laboratory work. Comprised of two coils fully enclosed in a polished wooden case with binding posts. Includes adjustable vibrator system, primary current polarity reversal and off-on switch, a condenser enclosed in the box and special alloy contacts. Spark gap at the discharge points can be adjusted by sliding rods back and forth. Requires 6-12 volt power source such as a battery. Spark length in air is 100mm. Other spark lengths are also available.