Bring “dead” batteries back to life with a toroid and the Joule Thief circuit.

Bring “dead” batteries back to life with a toroid and the Joule Thief circuit.

The Joule Thief (Wikipedia) is a well-known “instant gratification” hobby circuit that uses just a handful of components to pull off a pretty impressive parlor trick — using a single 1.5V battery, the Joule Thief can light a high-voltage blue or white LED that normally requires 3.5V or greater to turn on. Even more impressive, […]

Bring “dead” batteries back to life with a toroid and the Joule Thief circuit. Continue Reading