Feb 092017
Light sensitive alarm using LDR

This light sensitive alarm is very simple and works using, as main components, a transistor, an LDR and a relay.

The alarm activates when the illumination level changes from almost total darkness to a moderately high illumination level. When this happens the alarm is locked and the alarm signal, be it a light or a sound, remains active.

Sep 072016
SBS – Silicon Bidirectional Switch

The SBS – Silicon Bidirectional Switch is a symmetrical low power device used on trigger applications. The SBS is more versatile than the SIDAC.

It also has an additional terminal, which allows you to modify its trigger characteristics with small pulses of current.