What is Radio and How it works
What is Radio and its Working
A radio is a device for receiving and sending Speech or music over large areas by electromagnetic signals.
- Transmission: Information is sent out into the atmosphere from a Transmitting station. When someone speaks in the microphone at the radio station, sound waves are if converted into electrical fluctuating current. This current is converted into high frequency alternating current, which is allowed to pass in the transmitting antenna. The transmitting antenna produces radio waves with fluctuating amplitude. These waves are known as modulated carrier waves.
- Receiving: When the modulated carrier waves meet a receiving aerial, they generate fluctuating alternating current in it. This AC is converted into DC with the help of a rectifier. An earphone or a speaker is connected to the receiver. The DC energizes the electromagnet of the speaker and causes the diaphragm to vibrate. This produces the sound of same frequency as that at the radio station.
E-ink technology has another advantage – such displays require energy only when changing images, that is, when turning the pages of a book. Accordingly, the e-book itself has a much higher level of autonomy than a tablet, because the reader can work without recharging for a week. Manufacturers of e-books mark not even the battery life, but the number of pages, so that it is easier for the user to calculate how many books to read the charge of his reader will suffice