Images

history

By justinnn,10

  • telephone

    telephone transmission extends across and between major cities

  • adds

    Fleming invents the vacuum diode

  • call

    first telephone call

  • systems

    switching systems

  • at&t

    multiplexing concept

  • ringer

    first phone to combine ringer and handset

  • transmisson

    first commercial digital transmission

  • first 911 call is made

    in February 16 the first 911 call is made in Alabama

  • first portable cellphone made

    made by Martin cooper of motorola

  • U.S military start using cell phone technology

    start using fiber optics to improve communication

  • public cell phone test

    public test of new cellular tech

  • voice over

    the advent of voice over internet protocals

  • 100 million subscribers

    a lot of people using phones now