General purpose hobby circuit of a simple light fence security beeper is presented here. This circuit can be used as a door alarm, gate alarm, pathway alarm, etc. Any 12 Volt dc power supply can power ...

This luggage or bike alarm can be used while travelling by trains or bus and we generally lock our luggage using a chain-and-lock arrangement. But, still we are under tension, apprehending that ...

Learn to recognise different circuit symbols with these interactive learning resources for KS2 Science students aged 7-11 from BBC Bitesize.