*rotary dial*

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(a rotary dial is a component of a ‘telephone’ (or a ‘telephone switchboard’) that implements a ‘signaling technology’ in ‘telecommunications’ known as ‘pulse dialing’)

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(it is used when initiating a ‘telephone call’ to transmit the ‘destination telephone number’ to a ‘telephone exchange’)

(on the ‘rotary dial’, the digits are arranged in a ‘circular layout’ so that a ‘finger wheel’ may be rotated with 1 finger from the position of each digit to a ‘fixed stop position’, implemented by the ‘finger stop’, which is a ‘mechanical barrier’ to prevent further ‘rotation’)

(when released at the ‘finger stop’, the wheel returns to its ‘home position’ by ‘spring action’ at a speed regulated by a ‘governor device’)

(during this ‘return rotation’, the ‘dial’ interrupts the ‘direct electrical current’ of the ‘telephone line’ (aka the ‘local loop’) a specific # of times for each digit and thereby generates ‘electrical pulses’ which the ‘telephone exchange’ decodes into each ‘dialed digit’)

(each of the ’10 digits’ is encoded in sequences of up to ’10 pulses’ so the method is sometimes called decadic dialing)

(the first ‘patent for a ‘rotary dial’ was granted to ‘almon brown strowger (’29 november 1892’) as ‘USA patent 486,909’, but the ‘commonly-known form’ with ‘holes’ in the ‘finger wheel’ was not introduced until ~ 1904)

(while used in ‘telephone systems’ of the ‘independent telephone companies’, ‘rotary dial service’ in the ‘bell system’ in the ‘united states’ was not common until the introduction of the ‘western electric model 50AL’ in ‘1919’)

(from the ‘1980s’ onward, the ‘rotary dial’ was gradually supplanted byΒ ‘dual-tone multi-frequencyΒ push-button dialing’, first introduced to ‘the public’ at theΒ 1962 world’s fairΒ under the trade name “touch-tone”)

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(‘touch-tone technology’ primarily used a ‘keypad’ in form of a rectangular array of push-buttons for ‘dialing’)

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*WIKI-LINK*

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πŸ‘ˆπŸ‘ˆπŸ‘ˆβ˜œ*β€œTHE TELEPHONE”* ☞ πŸ‘‰πŸ‘‰πŸ‘‰

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*🌈✨ *TABLE OF CONTENTS* ✨🌷*

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πŸ”₯πŸ”₯πŸ”₯πŸ”₯πŸ”₯πŸ”₯*we won the war* πŸ”₯πŸ”₯πŸ”₯πŸ”₯πŸ”₯πŸ”₯