How does a remote change a channel?

Answer 1

Pushing a button to change the channel on a remote control begins a process that causes the remote to carry out the command. It works something like this:

1. You want to go to channel 13 and push these buttons on the remote control. This causes it to touch the contact beneath it, and this completes the "channel change" circuit on the integrated circuit board, which detects this.
2. The integrated circuit then sends the "channel change" command to the LED (Light-emitting diode) at the front of the remote. [LEDs are able to transmit visible, ultraviolet, and infrared waves and are very useful across a variety of disciplines.]
3. The LED sends a series of light pulses which corresponds to the numerical code that indicates which channel the TV should switch to.

(These numerical codes, also called binary commands, are each seven digits long. Each different command or number has a different binary command. For instance, on Sony TVs, the "volume up" command is 001 0010 while the "change to channel 13" command would read like this: 000 0000 000 0010 (there are 14 digits because the channel you want has 2 digits and each digit has it's own binary command).

On the TV set, the infrared receiver picks up the signal sent from the remote control and converts the light pulses back into the electrical signal. This signal is then passed to the microprocessor, which completes the command of changing the channel.