more at
http://phones.quickfound.net
"A young man sketches a generic human who takes us back through history to show us how humans developed a need to communicate and the devices to do so. Then shows us how telephones enable the modern mid-Sixties world. Part-animated by the master
John Hubley. Directed by
Jean Yarbrough..."
Public domain film from the
Prelinger Archives, slightly cropped to remove uneven edges, with the aspect ratio corrected, and mild video noise reduction applied.
The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original).
http://creativecommons.org/licenses/by-sa/
3.0/
http://en.wikipedia.org/wiki/
Telephone
A telephone, or phone, is a telecommunications device that permits two or more users to conduct a conversation when they are not in the same vicinity of each other to be heard directly. A telephone converts sound, typically and most efficiently the human voice, into electronic signals suitable for transmission via cables or other transmission media over long distances, and replays such signals simultaneously in audible form to its user. The word telephone has been adapted into the vocabulary of many languages. It is derived from the
Greek: τῆλε, tēle, "far" and φωνή, phōnē, "voice", together meaning "distant voice".
First patented in 1876 by
Alexander Graham Bell and further developed by many others, the telephone was the first device in history that enabled people to talk directly with each other across large distances. Telephones rapidly became indispensable to businesses, government, and households, and are today some of the most widely used small appliances.
The essential elements of a telephone are a microphone (transmitter) to speak into and an earphone (receiver) which reproduces the voice of the distant person. In addition, most telephones contain a ringer which produces a sound to announce an incoming telephone call, and a dial used to enter a telephone number when initiating a call to another telephone. Until approximately the
1970s most telephones used a rotary dial, which was superseded by the modern
DTMF push-button dial, first introduced by
AT&T; in
1963. The receiver and transmitter are usually built into a handset which is held up to the ear and mouth during conversation. The dial may be located either on the handset, or on a base unit to which the handset is connected. The transmitter converts the sound waves to electrical signals which are sent through the telephone network to the receiving phone. The receiving telephone converts the signals into audible sound in the receiver, or sometimes a loudspeaker. Telephones are a duplex communications medium, meaning they allow the people on both ends to talk simultaneously.
A landline telephone is connected by a pair of wires to the telephone network, while a mobile phone, such as a cellular phone, is portable and communicates with the telephone network by radio transmissions.
The public switched telephone network, consisting of telephone lines, fiberoptic cables, microwave transmission, cellular networks, communications satellites, and undersea telephone cables connected by switching centers, allows telephones around the world to communicate with each other. Each telephone line has an identifying telephone number. To initiate a telephone call the user enters the other telephone's number into a numeric keypad on the phone.
Graphic symbols used to designate telephone service or phone-related information in print, signage, and other media include ℡ (U+
2121), ☎ (U+260E), ☏ (U+260F), ✆ (U+2706), and ⌕ (U+
2315).
Although originally designed for simple voice communications, most modern telephones have many additional capabilities. They may be able to record spoken messages, send and receive text messages, take and display photographs or video, play music, and surf the
Internet. A current trend is phones that integrate all mobile communication and computing needs; these are called smartphones...
- published: 04 Nov 2014
- views: 1839