Panel ThProcure IR modules from an old VCR, Raphael writes “Some time ago, I came across the Lirc (Linux Infrared Remote Control) website and decided to build a serial port IR receiver. They had a list of suggested IR receiver modules, but I was unable to buy one, so I had to think of using something else. A IR Receiver module is usually a photodiode and a 38khz detector. Most of them have 3 pins. VCC, GND, an output pin. If a 38khz carrier is detected, the output pin will become active. Some modules are active low, and others are active high. It is sometimes required to use an inverter(eg: 7404) to get the correct signal.” Link.