How does a Fax Machine Work?

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Fax or Facsimile transmission is a system of sending information on paper by telephone lines. It transmits a copy of the information document to another person in another city or country. It can also transmit drawings in addition to printed text. Before sending a document, the fax machine tests the telephone line it is going to use. If it detects a faulty line, it automatically switches to a slower speed. This reduces the risk of losing the content of information during transmission. The document is scanned and the image is converted into electric signals. At the receiver's end of the telephone, another fax machine receives the signals, decodes them and prints out a copy of the original document.

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