How much high voltage?.....current?

[Richard Hull]

All fusors and accelerators of the electrostatic type use DC voltages or DC pulses to operate. All simple amateur systems, even neutron fusors use steady DC voltages fairly exclusively.

The simplest of demo devices with poor vacuum systems can light off at 800 volts. The show would be rather disappointing, being just a dull, diffuse, violet glow in and around the inner grid.

A creditable demo device suitable for high school show and tells/science fair exhibits, etc., would be OK with about 5 or 6KV applied and up to about 10 milliamperes of current.

A plus ultra demo device capable of showing star mode would demand a solid 10kv supply with up to 20 ma current capability.

X-rays begin around 12kv and go up at an alarming rate with further voltage increases.

Neutrons in most well made amateur fusor systems with dueterium fills can barely be detected at 10kv, but near 20kv they are really noticeable with about 10ma of supply current.

30 kilovolts is required to really start the system cooking so that even a poor detector will register plenty of neutrons.

Currents are limited only by the heating of the inner grid structure. It is a rare fusor that hits 30kv at 10ma and keeps an intact grid for more than a minute of operation.

A supply capable of maintaining a voltage of 50kv at 30 ma would be the ultimate amateur fusioneer's research supply. It would also be instant death to any who contacted the hot wire. There is little need for such a potent supply until about your fifth fusor.

Voltages and currents from a limited supply are a function of the pressure within the device and are often controlled by it.

Richard Hull