his Project ?Infrared Remote Switch? is used to Switch
On/Off an electrical appliances which may be Light, Fan etc
The Remote control used is an ordinary TV remote control
which should be pointed towards the Kit and by pressing
any button the device connected to the system will toggle
on every button press.
The above system is monitored and controlled by the 8 bit
Microprocessor. The Microprocessor continuously monitors
the Infrared sensor and if it sense infrared signal then it
latches the sensor and the microprocessor toggle the load
according to the software stored on the RAM.

The circuit is built around a 3-pin IR receiver (Siemens SFH-506-38 or equivalent) that can detect the 38kHz burst frequency generated by a TV remote control. (This IR receiver module has been covered previously in many projects published in EFY). The IR sensor output pin goes low when IR light is detected, firing the monostable (1 second) built around the NE555 timer. The mono output alternates the J-K flip-flop, whose Q output drives the relay through the SL100 npn (T1) transistor. LED2, LED3 and LED4 are used to display the status of each output stage during circuit operation. The Back-EMF D5 is used for protection. Transistor T1 is configured as an open collector output device to drive the nominal relay to 12 VDC. The circuit extracts the power from the 7805 voltage regulator. The capacitor C5 is soldered near the pins of the IR sensor to prevent noise and false shots. Capacitor C3 and resistor R3 also prevent false tripping of the monostable NE555. The monostable acts as a hysteresis unit of 1 second to restrict the flip-flop from being re-activated in one second. To activate any other 12V logic device, use the output via the relay coil terminals.