*the telephone* - -KINGDOM OF JOGA-

*a telephone is a ‘telecommunications device’ that permits 2 or more users to conduct a conversation when they are too far apart to be heard directly*

(a ‘telephone’ converts ‘sound’ (typically (+ 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)

(in 1876, scottish emigrant “alexander graham bell” was the first to be granted a ‘united states patent’ for a device that produced ‘clearly intelligible replication’ of the ‘human voice’)

(this instrument was 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’ / ‘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 in a distant location)

(in addition, most telephones contain a ringer which produces a sound to announce an ‘incoming telephone call’, and a ‘dial’ or ‘keypad’ 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(until approximately the 1970s most telephones used a ‘rotary dial’, which was superseded by the modern ‘DTMF push-button dial’, first introduced to the public by ‘AT&T’ in ‘1963’)

(the ‘receiver’ + ‘transmitter’ are usually built into a ‘handset’ which is held up to the ‘ear’ + ‘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’ permit ‘duplex communication’…)

(meaning they allow the people on both ends to talk simultaneously)

(the first ‘telephones’ were directly connected to each other from one customer’s ‘office’ (or ‘residence’) to another customer’s ‘location’)

(being impractical beyond just a few customers, these systems were quickly replaced by manually operated centrally located ‘switchboards’)

(this gave rise to ‘landline telephone service’ in which each ‘telephone’ is connected by a pair of ‘dedicated wires’ to a ‘local central office switching system’, which developed into ‘fully automated systems’ starting in the ‘early 1900s’)

(for greater ‘mobility’, various ‘radio systems’ were developed for ‘transmission’ between ‘mobile customer stations’ on ‘ships’ + ‘automobiles’ from the ‘1930s’ by the ‘mid-1900s’)

(the first ‘hand-held mobile phone’ was introduced for ‘personal service’ starting in 1973 by ‘motorola’)

(by the ‘late 1970s’, several ‘mobile telephone networks’ operated around the world)

(in ‘1983’, the ‘advanced mobile phone system’ (AMPS) was launched in the ‘united states’ + in other countries soon after, and offered a ‘standardized technology’ providing ‘portability’ for users within a region far beyond the ‘personal residence’ or ‘office location’)

(these ‘analog cellular systems’ evolved into ‘digital networks’ with…)

*better security*

*greater capacity*

*better regional coverage*

*lower cost*

(the ‘public switched telephone network’, with its ‘hierarchical system’ of many ‘switching centers’, interconnects ‘telephones’ around the world for ‘communication’ with each other)

(with the ‘standardized international numbering system’ (E.164), each ‘telephone line’ has an ‘identifying telephone number’, that may be called from any authorized ‘telephone’ on the network)

(although originally designed for ‘simple voice communications’, ‘convergence’ has enabled most modern ‘cell phones’ to have many additional ‘capabilities’)

(they may be able to…)

‘record spoken messages’

*send + receive ‘text messages’*

*’take’ + display ‘photographs’ (or ‘video’)*

*play ‘music’*

*play ‘games’*

*’surf’ the ‘internet”*

*do ‘road navigation’*

*immerse the ‘user’ in ‘virtual reality’*
(not quite ‘real’?)
(or ‘almost as ‘good’ as ‘reality’)
(aka ‘real life’)

(since 1999, the trend for ‘mobile phones’ is ‘smartphones’ that integrate all ‘mobile-communication/computing needs’)

*👨‍🔬🕵️‍♀️🙇‍♀️*SKETCHES*🙇‍♂️👩‍🔬🕵️‍♂️*

📚📖|/\-*WIKI-LINK*-/\|📖📚