thyristor

Even the solid-state thyristor, a cousin of the transistor invented in the 1950s, offered no great advantages over the tens or hundreds of kilometres that power grids tended to span.

Mr. Spira’s idea was to replace a rheostat, which controlled the current flow in an industrial dimmer by absorbing electrical energy on its way to a light source, with a thyristor, a type of transistor that interrupted the flow of power to the light.

Some bomb makers will also use other pieces of technology, like using a thyristor instead of connecting directly to the battery.

A thyristor acts as a switch when an electrical signal is sent to it.