Radio station

A radio station is a set of equipment necessary to carry on communication via radio waves. Generally, it is a receiver and/or transmitter, an antenna, and some smaller additional equipment necessary to operate them. Radio stations play a vital role in communication technology as they are heavily relied on to transfer data and information across the world.

More broadly, the definition of a radio station includes the aforementioned equipment and a building in which it is installed. Such a station may include several "radio stations" defined above (i.e. several sets of receivers and/or transmitters installed in one building but functioning independently, and several antennas installed on a field next to the building). This definition of a radio station is more often referred to as a transmitter site, transmitter station, transmission facility or transmitting station. An example of this definition is Bethany Relay Station of the Voice of America which had seven broadcast transmitters and could broadcast up to seven independent programs (even produced by different broadcasters) simultaneously, as well as several communications transmitters and receivers.

Radio broadcasting

Radio broadcasting is a unidirectional wireless transmission over radio waves intended to reach a wide audience. Stations can be linked in radio networks to broadcast a common radio format, either in broadcast syndication or simulcast or both. Audio broadcasting also can be done via cable radio, local wire television networks, satellite radio, and internet radio via streaming media on the Internet. The signal types can be either analog audio or digital audio.

In 2009, there were 3,494 radio broadcasting stations in the United States.

History

The earliest radio stations were simply radiotelegraphy systems and did not carry audio. For audio broadcasts to be possible electronic detection and amplification devices had to be incorporated.

The thermionic valve was invented in 1904 by the English physicist John Ambrose Fleming. He developed a device he called an "oscillation valve" (because it passes current in only one direction). The heated filament, or cathode, was capable of thermionic emission of electrons that would flow to the plate (or anode) when it was at a higher voltage. Electrons, however, could not pass in the reverse direction because the plate was not heated and thus not capable of thermionic emission of electrons. Later known as the Fleming valve, it could be used as a rectifier of alternating current and as a radio wave detector. This greatly improved the crystal set which rectified the radio signal using an early solid-state diode based on a crystal and a so-called cat's whisker. However, what was still required was an amplifier.

The Good Life

The Good Life or Good Life may refer to:

"The good life", a philosophical term for the life that one would like to live, originally associated with Aristotle.

Ethics and environmental philosophy

Film

Literature

Music

Songs

Form of the Good

Plato describes "The Form of the Good", or more literally "the idea of the good" (ἡ τοῦ ἀγαθοῦ ἰδέα), in his dialogue the Republic (508e2–3), speaking through the character of Socrates. Plato introduces several forms in his works, but identifies the Form of the Good as the superlative. This form is the one that allows a philosopher-in-training to advance to a philosopher-king. It cannot be clearly seen or explained, but once it is recognized, it is the form that allows one to realize all the other forms.

Usages in The Republic

The first references we see in The Republic to the Form of the Good can be found within the conversation between Glaucon and Socrates (454 c–d). When trying to answer such difficult questions pertaining to the definition of justice, Plato identifies that we should not “introduce every form of difference and sameness in nature” instead we must focus “on the one form of sameness and difference that was relevant to the particular ways of life themselves” which is the Form of the Good. This Form is the basis for understanding all other Forms, it is what allows us to understand everything else. Through the conversation between Socrates and Glaucon (508 a–c) Plato analogizes the Form of the Good with the sun as it is what allows us to see things. Here, Plato describes how the sun allows for sight. But he makes a very important distinction, “sun is not sight” but it is “the cause of sight itself.” As the sun is in the visible realm, the Form of Good is in the intelligible realm. It is “what gives truth to the things known and the power to know to the knower”. It is not only the “cause of knowledge and truth, it is also an object of knowledge”.

Radio

Radio is the use of radio waves is to carry information, such as sound, by systematically modulating some property of electromagnetic energy waves transmitted through space, such as their amplitude, frequency, phase, or pulse width. When radio waves strike an electrical conductor, the oscillating fields induce an alternating current in the conductor. The information in the waves can be extracted and transformed back into its original form.

Radio systems need a transmitter to modulate (change) some property of the energy produced to impress a signal on it, for example using amplitude modulation or angle modulation (which can be frequency modulation or phase modulation). Radio systems also need an antenna to convert electric currents into radio waves, and vice versa. An antenna can be used for both transmitting and receiving. The electrical resonance of tuned circuits in radios allow individual stations to be selected. The electromagnetic wave is intercepted by a tuned receiving antenna. A radio receiver receives its input from an antenna and converts it into a form usable for the consumer, such as sound, pictures, digital data, measurement values, navigational positions, etc. Radio frequencies occupy the range from a 3 kHz to 300 GHz, although commercially important uses of radio use only a small part of this spectrum.