Decades ago it was a luxury to have a TV remote that could only do the most basic of functions such as change channel, on/off and volume. Nowadays it’s common to have a TV made by a different company from your DVD player, also you may have Sky and possibly a surround sound system. This could mean four different remotes, and as is always the case whenever you need the remote you can never find it, so with four remotes that’s pretty annoying.
This is where universal remotes come in. Most remote controls communicate with their appliances by sending infrared signals, whereas more long distance applications use radio waves. Whenever you press a button on a TV remote you are triggering a specific numerical code that manifests itself as a unique series of these infrared pulses. The TV has been programmed to recognise these pulses as instructions such as turn on or change channel and so on.
Not only do different instructions have different codes but also appliances made by different manufacturers have different manufacturing codes. Universal remotes work by ‘learning’ these different codes or having the codes programmed in manually by the user allowing them to work with multiple devices. Does this assist in helping to locate the remote when you need it most? Probably not.
Rik Sargent, Science Museum