Wireless On Off Switch
Small and simple circuit, Suitable for home appliances Normally home appliances are controlled by means of switches, sensors, etc. However, physical contact with switches may be dangerous if there is any shorting. The circuit described here requires no physical contact for operating the appliance. You just need to move your hand between the infrared LED (D2) and the phototransistor (Q1). The infrared rays transmitted by D2 is detected by the phototransistor to activate the hidden lock, flush system, hand dryer or else. This circuit is very stable and sensitive compared to other AC appliance control circuits. It is simple, compact and cheap. Current consumption is low in milliamperes. The circuit is built around an IC CA3140, D2, phototransistor and other discrete components. Circuit Diagram: Parts: R1 = 470R R2 = 100K R3 = 3.3K R4 = 10K D1 = 1N4007 D2 = IR LED Q1 = L14F1 RL = 5Vdc Relay IC = CA3140 Q2 = BC548 Circuit Operation: When regulated 5V is connected to the circuit, D2 emits i...