Here is a simple tester for checking the basic operations of an infrared remote control unit. It is low-cost and easy to construct. The tester is built around infrared receiver module TSOP1738. Operation of the remote control is acknowledged by a tone from the buzzer. The circuit is sensitive and has a range of approximately five meters. The integrated IR receiver detects, amplifies and demodulates IR signals from the remote control unit. The piezo buzzer connected at its output sounds to indicate the presence of signal from the remote control unit.
As shown in diagram output pin 3 of IR receiver module TSOP1738 (IR1) normally remains high and the B1 is in silent mode. When the IR receives an infrared signal, its output goes low and, as a result, the B1 sounds to indicate the reception of signal from the remote (such as TV remote control unit). Assemble the circuit on a general-purpose PCB and enclose in a cabinet. Make sure that the IR receiver module is placed on the front panel of the cabinet so that it can receive the IR signals easily. Before soldering/connecting the shunt regulator and IR module, refer for the pin configuration.