- Published in issue 7/1996 on page 101
Inexpensive emergency light
The low-cost circuit charges two nickel-cadmium cells from the mains to provide a stand-by power supply for a two-lamp emergency light which is automatically switched on in the event of a mains failure. The best place to moint the circuit is probably in the electricity locker in your home. That location is also convenient because the 4.5 V alternating voltage may be tapped from the doorbell transformer.