History of Telecommunications(Chapter 1)ENGR 475 TelecommunicationsHarding UniversityAugust 22, 2006

Jonathan White

OutlineWhat is Telecommunications?The time before phonesWho actually invented the telephone?1900 1982 Regulated AT & T Monopoly1982 Long Distance Competition1996 Local dial tone competition2000 and Beyond WWW, internet phones

Telecomm. DefinitionTransmission of signals over a distance for the purpose of communication.The word telecommunication is adapted from a French word. It is a compound of the Greek prefix tele, meaning 'far off', and communication, meaning 'to transfer information'.3 parts:TransmitterMediumReceiver

Telecomm. DefinitionWhat are some examples of Telecommunication systems?Name the mediums for each.

Time before Phones1831 Professor Joseph Henry, Albany, NY Ring a bell at a distance by connecting and disconnecting wires.May 24, 1844 -- Samuel Morse sends from Baltimore to Washington, D.C. What hath God wrought.Numbers 22:23Morse code

Time before Phones1854 25,000 miles of telegraph wires have been laid across the US.Train schedules, weather, important news1864 A telegraph line spans the entire continental USWestern Union is formed.1866 Trans Atlantic telegraph8 words a minuteVery costly

Who invented the Phone?1861 Johann Reiss, a German physics teacher, completed an almost working version of a telephone.Used: sausage skin, beer barrel, platinum barFunction: sent musical notes to a receiver that could play them.Downsides: same idea as the telegraph; making and breaking a circuit. Not continuous.

Who invented the Phone?1871 Antonio Meucci, an Italian immigrant living in New York, files a caveat (an announcement of invention) of a talking telegraph. However, due to financial hardships, he is unable to pay for a full patent when the caveat is due 3 months later.Had a working prototype.Honored in 2002 by Congress.

Who invented the Phone?February 14, 1876 (Valentines Day), Boston, MA US Patent Office9:30 AM Elisha Gray (or his lawyer) files a caveat for an invention described as the art of transmitting vocal sounds or conversations telegraphically through an electric circuit.11:30 AM Alexander Graham Bells lawyer files AND pays for a patent described as "Improvements in Telegraphy.2:30 PM Elisha Grays caveat is paid for so that a patent can be granted.

Who invented the Phone?Alexander Graham Bell (1867)Elisha Gray (1878)

Who invented the Phone?US Patent 174,465Said to be the most valuable patent everOver 600 lawsuits were filed in the 1800s over it.Awarded to:Bell in 1876Bell tried to sell the patent rights to Western Union in 1876 for $100,000.

Western Union said the patent wasworthless; whod want voice when the telegraph still work?

Who invented the Phone?More about Alexander Graham Bell:Wife was deaf.Wanted to communicate to her at a distance.1874 phonoautograh made out of a dead mans ear.Ears membrane vibrated differently based on the intensity of the sound. Used to switch a lever on and off and write.He thought that by using a membrane to convert sounds of varying intensity into electrical current of varying intensity and then reversing the process on the other end with another membrane, he could replicate speech over long distances.

Who invented the Phone?Bells first phone used a metal disk attached to a rod floating in acid to create a variable resistance.A change in intensity made the disk vibrate differently.1877 Thomas Edison invents the carbon microphone.Used in phones until late 1970sA phone produced from around 1900 on will still work on todays phone network.

Who invented the Phone?When the patents were filed, Bells phone didnt work.Grays was a better designMarch 10, 1876:Mr. Watson, Come here! I want you!First telephone message.A one wire, copper system was used at first.A 2 wire system was invented in 1881 - Much clearer conversation. - Insulated by cotton/rubber and twisted

Who invented the Phone?Alexander Graham Bell was awarded the first US patent for a device which ultimately became the telephone. Who invented the telephone is very debatable.

1877 - 19001877 Bell telephone company formed.1877 Western Union forms the American Speaking Telephone Company using Grays invention.All phones are party lines initially.1877 In July, a druggist in New Hartford, Connecticut invents the switchboard.

1877 - 1900

1877 - 1900Ringers:Thumper (pre switchboard)1878: Thomas Watson invents the MagnetoAn AC current sent down the line that would make a hammer move back and forth between 2 bells.The first non-voice signal that the telephone system used.

1877 - 19001891 An undertaker named Almon Strowger in Kansas City, Missouri invents the first phone that uses a keypad Also uses automatic connections from the central office using electromagnetic rods.Automatic switching didnt take hold, however.1921 first automatic system installed in Omaha, Nebraska.It wasnt until after well after WW 2 that automatic systems were the norm.Think of the Andy Griffith Show.

1877 - 1900Strowgers Phone

1877 - 19001879 Because of the measles epidemic in Massachusetts, a doctor recommends numbering phone lines instead of using names.The system was eventually expanded to a 2 letter, 5 number systemThe first 2 letters identified the state / CO.The next number identified the CO.The last 4 numbers identified the customer.PE 6-5000This system was used until the 1950s and beyond.

1877 - 19001896 Invention of the rotary dial phone.Less wiring and cheaper.

1900 1982 Monopoly1899 American Bell is acquired/renamed AT & T American Telephone and Telegraph. Many companies entered the phone market around this time.None were interconnected.You had to have the same carrier.You had to buy your phone from your provider and they owned the network.AT & T eventually become a natural monopoly by the 1920s for long distance calls.This was allowed by law.No competition and expensive.

1900 1982 MonopolyJanuary 8, 1982 AT & T is broken up:AT & T was broken up into 23 Bell Operating Companies, that would compete against AT & T in the telephone long distance market.AT & T had to let other companies use their network.AT & T would only be in the long distance market Very Bad.AT & T was bought by one of its children (SBC) in 2005.

1996 Telecommunications ActFebruary 1996 There can now be competition in the local market.The telephone industry was deregulated.You can now get local, long distance, cellular, high speed Internet, and digital cable all from one provider, all over the same network.Prices go way down.Who owns the Internet? Who owns the telephone network? Are they even separate networks?Circuit switched vs. packet switched.QOS

2000 and BeyondThe telephone network is now all digital, up to the end users home (local loop).Some are digital DSL.Most are analog phones.Is telephony going to become just another application of the Internet?MaybeMany applications exist that we havent talked about:Caller ID (1991), 911 emergency service (1968),cellular phones (1984)