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IR Remote Switch for Home Appliance

10/13/2011 Category: Basic, Control, Remote

If you are looking for simple ON-OFF remote switch for your home appliance then this InfraRed remote control circuit is suit for it. This circuit allows you to turn on/off your home appliance (lamp, ran, radio, etc) using any type TV, VCD or DVD remote control with range up to 10 meters. The circuit is easy to build and consist of familiar components like IC CD4017 (decade counter) and Infrared receiver module TSOP1738.
IR remote switch on off schematic

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How it works?
The 38 kHz infrared (IR) rays generated by the remote control are received by IR receiver module TSOP1738 of the circuit. Pin 1 of TSOP1738 is connected to ground, pin 2 is connected to the power supply through resistor R5 and the output is taken from pin 3. The output signal is amplified by transistor T1 (BC558). The amplified signal is fed to clock pin 14 of decade counter IC CD4017 (IC1). Pin 8 of IC1 is grounded, pin 16 is connected to Vcc and pin 3 is connected to LED1 (red), which glows to indicate that the appliance is ‘off’. The output of IC1 is taken from its pin 2. LED2 (green) connected to pin 2 is used to indicate the ‘on’ state of the appliance.

Pin 2 of IC1 connected transistor T2 (BC548) to drives relay RL1. Diode 1N4007 (D1) acts as a freewheeling diode. The controlled appliance is connected between the pole of the relay and neutral terminal of mains. It connected to live terminal of AC mains via normally opened (N/O) contact when the relay energizes.