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A variant of the 1950s L-3 system was designed in the early 1960s to provide for land line connections between key military command and control facilities in the United States. Starting with L-3I (improved) the system was upgraded to be able to withstand nuclear attack. The system consisted of over 100 main stations and 1000 individual repeater ...
HBO was the first true premium cable (or "pay-cable") network as well as the first television network intended for cable distribution on a regional or national basis; however, there were notable precursors to premium cable in the pay-television industry that operated during the 1950s and 1960s (with a few systems lingering until 1980), as well ...
Electrical telegraphy is a point-to-point text messaging system, primarily used from the 1840s until the late 20th century. It was the first electrical telecommunications system and the most widely used of a number of early messaging systems called telegraphs, that were devised to send text messages more quickly than physically carrying them.
Contemporary map of the 1858 transatlantic cable route. Transatlantic telegraph cables were undersea cables running under the Atlantic Ocean for telegraph communications. . Telegraphy is an obsolete form of communication, and the cables have long since been decommissioned, but telephone and data are still carried on other transatlantic telecommunication
From the 1850s until well into the 20th century, British submarine cable systems dominated the world system. This was set out as a formal strategic goal, which became known as the All Red Line. [51] In 1896, there were thirty cable-laying ships in the world and twenty-four of them were owned by British companies.
Large voltages were used to attempt to overcome the electrical resistance of their tremendous length but the cables' distributed capacitance and inductance combined to distort the telegraph pulses in the line, reducing the cable's bandwidth, severely limiting the data rate for telegraph operation to 10–12 words per minute.
Greek hydraulic semaphore systems were used as early as the 4th century BC. The hydraulic semaphores, which worked with water filled vessels and visual signals, functioned as optical telegraphs. However, they could only utilize a very limited range of pre-determined messages, and as with all such optical telegraphs could only be deployed during ...
At the outset, cable systems only served smaller communities without television stations of their own, and which could not easily receive signals from stations in cities because of distance or hilly terrain. In Canada, however, communities with their own signals were fertile cable markets, as viewers wanted to receive American signals.