English-German dictionary of Electrical Engineering and Electronics. 2013.
Telephone exchange — A telephone operator manually connecting calls with cord pairs at a telephone switchboard. In the field of telecommunications, a telephone exchange or telephone switch is a system of electronic components that connects telephone calls. A central… … Wikipedia
Charles Wheatstone — Wheatstone, drawn by Samuel Laurence in 1868 Born 6 … Wikipedia
Time signal — These automatic signal clocks were synchronized by telegraphy in 1905 before the widespread use of radio A time signal is a visible, audible, mechanical, or electronic signal used as a reference to determine the time of day. Contents 1 Audible… … Wikipedia
