Long Distance IR Transmitter Circuit Document

Long distance IR transmitter circuit document

Here is a simple circuit that will give you a pretty long range. It uses three infrared transmitting LEDs (IR1 through IR3) in series to increase the radiated power. Further, to increase the directivity and so also the power density, you may assemble the IR LEDs inside the reflector of a torch.

Assemble the circuit on a general purpose PCB. Use switch S2 for power "on"/"off" control. Commercially available IR receiver modules (e.g., TSOP1738) could be used for efficient reception of the transmitted IR signals.