Advantages of Morse Code In the modern age, the Morse code is still as relevant as it was in the days of old. Here are the advantages of Morse code. Cheap
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- Telegraphic improvements[edit]
Expansion[edit]As well as the rapid expansion of the use of the telegraphs along the railways, they soon spread into the field of mass communication with the instruments being installed in post offices. The era of mass personal communication had begun. Telegraph networks were expensive to build, but financing was readily available, especially from London bankers. By 1852, National systems were in operation in major countries:[53][54]
The New York and Mississippi Valley Printing Telegraph Company, for example, was created in 1852 in Rochester, New York and eventually became the Western Union Telegraph Company.[57] Although many countries had telegraph networks, there was no worldwide interconnection. Message by post was still the primary means of communication to countries outside Europe.
Telegraphy was introduced in Central Asia during the 1870s.[59] Telegraphic improvements[edit]Wheatstone automated telegraph network equipment A continuing goal in telegraphy was to reduce the cost per message by reducing hand-work, or increasing the sending rate. There were many experiments with moving pointers, and various electrical encodings. However, most systems were too complicated and unreliable. A successful expedient to reduce the cost per message was the development of telegraphese. The first system that did not require skilled technicians to operate was Charles Wheatstone's ABC system in 1840 in which the letters of the alphabet were arranged around a clock-face, and the signal caused a needle to indicate the letter. This early system required the receiver to be present in real time to record the message and it reached speeds of up to 15 words a minute. In 1846, Alexander Bain patented a chemical telegraph in Edinburgh. The signal current moved an iron pen across a moving paper tape soaked in a mixture of ammonium nitrate and potassium ferrocyanide, decomposing the chemical and producing readable blue marks in Morse code. The speed of the printing telegraph was 16 and a half words per minute, but messages still required translation into English by live copyists. Chemical telegraphy came to an end in the US in 1851, when the Morse group defeated the Bain patent in the US District Court.[60] For a brief period, starting with the New York–Boston line in 1848, some telegraph networks began to employ sound operators, who were trained to understand Morse code aurally. Gradually, the use of sound operators eliminated the need for telegraph receivers to include register and tape. Instead, the receiving instrument was developed into a "sounder", an electromagnet that was energized by a current and attracted a small iron lever. When the sounding key was opened or closed, the sounder lever struck an anvil. The Morse operator distinguished a dot and a dash by the short or long interval between the two clicks. The message was then written out in long-hand.[61] Royal Earl House developed and patented a letter-printing telegraph system in 1846 which employed an alphabetic keyboard for the transmitter and automatically printed the letters on paper at the receiver,[62] and followed this up with a steam-powered version in 1852.[63] Advocates of printing telegraphy said it would eliminate Morse operators' errors. The House machine was used on four main American telegraph lines by 1852. The speed of the House machine was announced as 2600 words an hour.[64] A Baudot keyboard, 1884 David Edward Hughes invented the printing telegraph in 1855; it used a keyboard of 26 keys for the alphabet and a spinning type wheel that determined the letter being transmitted by the length of time that had elapsed since the previous transmission. The system allowed for automatic recording on the receiving end. The system was very stable and accurate and became accepted around the world.[65] The next improvement was the Baudot code of 1874. French engineer Émile Baudot patented a printing telegraph in which the signals were translated automatically into typographic characters. Each character was assigned a five-bit code, mechanically interpreted from the state of five on/off switches. Operators had to maintain a steady rhythm, and the usual speed of operation was 30 words per minute.[66] By this point, reception had been automated, but the speed and accuracy of the transmission were still limited to the skill of the human operator. The first practical automated system was patented by Charles Wheatstone. The message (in Morse code) was typed onto a piece of perforated tape using a keyboard-like device called the 'Stick Punch'. The transmitter automatically ran the tape through and transmitted the message at the then exceptionally high speed of 70 words per minute. Download 0.84 Mb. Do'stlaringiz bilan baham: |
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