A high-voltage generator (8 kV AC, 50 mA heavy iron core neon sign transformer) is housed in a wooden box and connected to two long brass electrodes. The electrodes are kept in place by two porcelain insulators. In order to facilitate an electrical discharge between the two main electrodes, a shorter auxiliary electrode is located between them. This third electrode can start the discharge but, due to the high resistance in series to it, is not capable to sustain it.
The main electrodes can be easily separated from the base block by removing a few screws for transportation or for their replacement if damaged.
A main switch block, including the mains fuses, is placed on the back side of the wooden box. On the front side, a rotary knob has the function of the operation switch. Both of these switches must be closed for the Jacob's Ladder to be operational.
Electrical discharges are generated between the two main electrodes, starting from their lower part and moving up to their top edges in a repetitive manner.
The electrodes are shielded by a clear acrylic tube, which is kept in place by four small brass balls. The shield can be optionally removed for installations where security is ensured by other means (e.g. a windowed room with no access).
