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The page of Gauss's laboratory notebook containing both his code and the first message transmitted, as well as a replica of the telegraph made in the 1850s under the instructions of Weber are kept in the faculty of physics at the University of Göttingen, in Germany. Prime examples are countries such as Austria, Germany and Switzerland that utilize AC technology based on 16 2/3 Hz. Interlocked MC Cables are also highly versatile. Electrical cables are used to connect two or more devices, enabling the transfer of electrical signals or power from one device to the other. Currents that flow solely in reaction to these properties, (which together with the resistance define the impedance) constitute reactive power flow, which transmits no power to the load. An electric current was sequentially applied by the sender through the various wires representing each letter of a message; at the recipient's end, the currents electrolysed the acid in the tubes in sequence, releasing streams of hydrogen bubbles next to each associated letter or numeral. Pavel Schilling subsequently improved its apparatus by reducing the number of connecting wires from eight to two. Using one wire for each letter of the alphabet, a message could be transmitted by connecting the wire terminals in turn to an electrostatic machine, and observing the deflection of pith balls at the far end.

The alphabet was encoded in a binary code that was transmitted by positive or negative voltage pulses which were generated by means of moving an induction coil up and down over a permanent magnet and connecting the coil with the transmission wires by means of the commutator. In frequency signaling, the generating units match the frequency of the power transmission system. The French TGV (High Speed Train) formation has a power car at each end of the train but only runs with one pantograph raised under the high speed 25 kV AC lines. A sophisticated control system is required to ensure that power generation closely matches demand. The most basic cable system operates on one single cable loop, while others have multiple loops as well as several stationary cable lines. The two stations of Schilling's telegraph were connected by eight wires; six were connected with the galvanometers, one served for the return current and one for a signal bell. Schilling's telegraph was tested on a 5-kilometre-long (3.1 mi) experimental underground and underwater cable, laid around the building of the main Admiralty in Saint Petersburg and was approved for a telegraph between the imperial palace at Peterhof and the naval base at Kronstadt.

Offering his invention to the Admiralty in July 1816, it was rejected as "wholly unnecessary". He was apparently unaware of Schweigger's invention at the time, which would have made his system much more sensitive. At first, Gauss and Weber used the telegraph to coordinate time, but soon they developed other signals and finally, their own alphabet. Since all the circuit conductors required can be installed in a cable at one time, installation labor is saved compared to certain other wiring methods. Schilling was also one of the first to put into practice the idea of the binary system of signal transmission. Optical fibers can be included in the stranded conductors of a transmission line, in the overhead shield wires. High-voltage direct current (HVDC) systems require relatively costly conversion equipment that may be economically justified for particular projects such as submarine cables and longer distance high capacity point-to-point transmission. The non-BS 1363 plug is inserted into the contacts, and the hinged body of the conversion plug is closed and fixed shut to grip the plug. This is a similar level of protection to that seen for portable appliances in other countries, but less than the protection offered by the BS 1363 fused plug.

Maud Lucas Lancaster mentions an earthed iron-clad plug and socket by the English firm of A. Reyrolle & Company. The BS 4573 socket is for use in rooms other than bathrooms. The telegraph had a separate wire for each of the 26 letters of the alphabet and its range was only between two rooms of his home. The first telegram in the United States was sent by Morse on 11 January 1838, across two miles (3 km) of wire at Speedwell Ironworks near Morristown, New Jersey, although it was only later, in 1844, that he sent the message "WHAT HATH GOD WROUGHT" over the 44 miles (71 km) from the Capitol in Washington to the old Mt. Clare Depot in Baltimore. The message was then written out in long-hand. The telegraph receiver's operator would watch the bubbles and could then record the transmitted message. Thus, messages could be conveyed electrically up to a few kilometers (in von Sömmering's design), with each of the telegraph receiver's wires immersed in a separate glass tube of acid. The Schilling telegraph, invented by Baron Schilling von Canstatt in 1832, was an early needle telegraph.

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