This circuit has been designed to complement the ‘Simple IR Transmitter’ and to decode its transmitted signals. The similarity to the transmitter can be clearly seen: the received data is decoded by a shift register (74HC4094), which again is clocked by a counter/oscillator (74HC4060). The receiver is started by the first edge from the IR-receiver module, which triggers monostable IC5a. The output of the module is active-Low, so the negative trigger input is used. The monostable used is a 74HC4538, which is re-triggerable. By connecting the Q-output to the positive trigger input, IC5 is prevented from being triggered whilst it has an active output.