hi,
how can a remote control reciever distinguish between two buttons. when I click on the power button on the remote control how the tv ( for example) distinguishes it from any other button. is it using frequency?each button has a corresponding frequency? how is that? how it is generated and how it is analyzed by the reciever
Hello,
The world's first remote controls were radio-frequency devices that directed German naval vessels to crash into Allied boats during WWI. In WWII, remote controls detonated bombs for the first time. The end of the great wars left scientists with a brilliant technology and nowhere to apply it. Sixty years later, some of us spend an hour looking for the remote before we remember there are buttons on the TV.
Now a days infrared technology used in most home theaters, look at the difference between IR and RF remotes, find out the difference between a "universal" and a "learning" remote and check out some of the other high-tech features you can find on remotes today, like PC connectivity, RF extenders and macro commands.
There were remotes using ultrasound tranduceres before infrared LED's came into existance. Necessity is the mother of invention.
Similar is "Morse code". See how coding is adopted for particular needs.