Some of the first remote controls available to consumers used sound, visible light, or even just wires to communicate with their parent device. It was many years between these first rudimentary remotes before they standardized around infrared or RF signaling. Even then it was a while before remote controls were reliable enough to not have to think about anymore. They’ve gotten so good now that there are small modules available that let us quickly build these devices to perform all manner of tasks.

[Igor Brichkov] is demonstrating this project because his garage door remote control suddenly stopped working. The RF receiver and transmitter circuits are readily available and inexpensive, but they need some support circuitry to work properly. The transmitter is paired with an encoder which is provided a binary code by wiring various pins to power and ground. This “code” is sent to the receiver which has a decoder and listens for that specific code. When the codes match it changes the state of one of its pins, which is used in this case to short the garage door’s remote terminals and signal it to open the door.

Although the resulting handheld remote with its single button looks a bit like something from 1950s science-fiction, it’s an effective solution. Especially when compared to possibly trying to reprogram a proprietary remote, find one from a company that doesn’t exist anymore, or rebuild one that operates on a bizarre frequency. With access to the physical hardware, it turns out a lot of things are controlled by just shorting pins together, and anything can do that from wires to RF transmitters.