Wireless data transfer can be useful for a variety of projects. I stumbled upon a very low cost emitter+receiver modules pair, and planned to use it for some time now. There are a few variants available on the market, but they do quite the same thing, just the operating frequency might be different (315MHz / 418MHz / 433MHz/ 915MHz): The emitter usually has 3 pins (VCC->5V, GND, DATA), with a…