The antennas have existed for a long time. The two most common antenna types we often encounter are the television antenna and the radio antenna. Antennas are used to transmit and receive electromagnetic waves. Without an antenna, our TV and radio could not take a signal from the stations. The number of channels your TV can display depends on the power of the antenna and how the signals can be suppressed. The position of the antenna, its quality and its climate can affect the quality of the transmission as well as the number of stations that your device can remove.
|image from WirelesSHack|
A television antenna has been specifically designed to receive signals which are generally transmitted at frequencies of 41 to 250 MHz in the high frequency (VHF) band and 470 to 960 MHz in the UHF band in different countries of the world . Several antennas are designed differently. TV antennas can be indoors or outdoors. An internal antenna, also called half-wave dipole antenna, is usually small. They have "ears", which can be adjusted in lengths to increase the signal. However, these antennas are not as good as mounted on roofs or outdoors. External antennas are usually larger and can receive better signals and more. The problem with these antennas is that it can be easily affected by the weather. For example, if there is a strong wind blowing outside, you can change the position of the antenna that interferes with the signal. The disadvantage of external antennas is that they can be relatively expensive. Another factor affecting the quality of the received signal is its position relative to the transmitter. If you are near the transmitter, the signals you would definitely get are of better quality.
|image from Wikimedia Commons|
How a radio antenna works is identical to a television antenna. The signals are transmitted when the transmitter applies a high-frequency current to the antenna connections which radiate this energy in the form of radio waves, which may also be called electromagnetic waves.