| Electrical Communication is a free textbook on the basics of communication technology. See the editorial for more information.... |
|
Home  Telegraph Systems Facsimile Transmission |
|
 Search the VIAS Library | Index
|
  |
Facsimile TransmissionSeveral facsimile methods have been developed. In some systems the message, picture, or drawing to be sent is scanned with a light beam, and corresponding electric impulses are produced with a phototube. In other systems a special paper called Teledeltos recording paper is used at both the sending and receiving ends. This is a coated conducting paper which is caused to become black at a point where electric current passes through it. It is not affected by light and requires no "photographic" processing.15 When using Teledeltos paper for transmitting information, the message is impressed on the paper with a soft lead pencil or from a special carbon paper. As the message is written, a film on the surface is ruptured, and a low resistance path through the paper is formed at each point. This makes possible an electric method of scanning and transmission.44 A system transmitting from a sheet such as a telegraph blank is called the Telefax.15 A system transmitting from a written message on a tape is called a Teletape.44
|
|
| Home Telegraph Systems Facsimile Transmission |
|
Last Update: 2011-05-30