Extender/Repeater Device for IR Remote Control

Overview

The goal of the project is to show how an IR remote control extender/repeater was built in order for electronic appliances from a remote location to be controlled.

Details

The three main parts that comprise the circuit include the IR receiver module, a 555 timer configured as an oscillator, and the output/emitter stage. The IR signal from remote control is received by the IR detector module and the signal is re-emitted to the appliance by the two IR LEDs. Using some wires, the IR emitting LEDs can be placed near the device to be controlled while keeping the main unit close to the location of the remote control.

The infrared receiver TSOP1738 running at 38kHz receives the IR signal. A demodulated signal that signifies the low frequency control pulses is obtained at the output of infrared receiver which is powered by a 5V supply. The 555 timer starts to oscillate at a preset frequency for the duration of each data pulse when HIGH control pulses are appearing on TSOP1738 output. The optical indicator of the output signal is represented by the red LED as the circuit uses a 9V battery to obtain power.