Homemade High Voltage Capacitor

You can make a Leyden jar for high-voltage experiments.

You can make a high voltage capacitor yourself from simple materials. Designs, such as the Leyden jar, have worked for experimenters for hundreds of years. Since high voltages are hazardous, pay attention to safety issues to avoid injury.

Safety

When working around high voltage equipment, wear safety goggles, neoprene gloves and thick, rubber-soled shoes or boots. Always discharge the capacitor before touching or storing it.

Design

The Leyden jar, developed in the 1700s, is a practical, high-voltage capacitor you can make at home. It consists of a glass jar lined inside and out with metal. The glass isolates the metal layers electrically and holds the charge. An electrode passing through an insulating lid touches the inside metal layer.

Materials

You can use aluminum foil for the metal inside and outside the jar. A clean glass or plastic jar serves as the capacitor's body. A plastic screw-lid seals the jar and holds a wire passing from the outside to the metal inside the jar.

Discharge

If you make the capacitor, you'll need a discharge wand. Use a bent length of metal tubing fixed to an insulated wood or plastic handle. To discharge, touch one end of the tubing to the top electrode and the other end to the metal on the jar's outside.

References

• Florida State University: Leyden Jar Tutorial