telephone current
101telecommunications media — Introduction equipment and systems metal wire, terrestrial and satellite radio, and optical fibre employed in the transmission of electromagnetic signals. Transmission media and the problem of signal degradation Every… …
102Coaxial cable — RG 59 flexible coaxial cable composed of: A: outer plastic sheath B: woven copper shield C: inner dielectric insulator D: copper core Coaxial cable, or coax, has an inner conductor surrounded by a flexible, tubular insulating layer, surrounded by …
103Skin effect — Skin depth redirects here. For the depth (layers) of biological/organic skin, see skin. Skin effect is the tendency of an alternating electric current (AC) to distribute itself within a conductor with the current density being largest near the… …
104Copper wire and cable — Copper has been used in electric wiring since the invention of the electromagnet and the telegraph in the 1820s.[1][2] The invention of the telephone in 1876 proved to be another early boon for copper wire.[3] Today, despite competition from… …
105Alexander Graham Bell honors and tributes — Alexander Graham Bell c.1918–1919 Alexander Graham Bell honours and tributes include honours bestowed upon him and awards named for him …
106china — /chuy neuh/, n. 1. a translucent ceramic material, biscuit fired at a high temperature, its glaze fired at a low temperature. 2. any porcelain ware. 3. plates, cups, saucers, etc., collectively. 4. figurines made of porcelain or ceramic material …
107China — /chuy neuh/, n. 1. People s Republic of, a country in E Asia. 1,221,591,778; 3,691,502 sq. mi. (9,560,990 sq. km). Cap.: Beijing. 2. Republic of. Also called Nationalist China. a republic consisting mainly of the island of Taiwan off the SE coast …
108electromagnet — /i lek troh mag nit/, n. a device consisting of an iron or steel core that is magnetized by electric current in a coil that surrounds it. [1815 25; ELECTRO + MAGNET] * * * Device consisting of a core of magnetic material such as iron, surrounded… …
109Nikola Tesla — Tesla, aged 37, 1893, photo by Sar …
110Impedance matching — In electronics, impedance matching is the practice of designing the input impedance of an electrical load (or the output impedance of its corresponding signal source) to maximize the power transfer and/or minimize reflections from the load.… …
