VII. Прочитайте следующий текст и ответьте на вопрос: Since when has the Federal Communications Commission issued various commercial “radiotelephone” licenses and permits?
Radiotelephone.
A radiotelephone is a communications system for transmission of speech over radio. Radiotelephone systems are not necessarily interconnected with the public “land line” telephone network. “Radiotelephone” is often used to describe the usage of radio spectrum where it is important to distinguish the type of emission from, for example, radiotelegraph or video signals. Where a two-way radio system is arranged for speaking and listening at a mobile station, and where it can be interconnected to the public switched telephone system, the system can provide mobile telephone service.
Since the 1930s the Federal Communications Commission has issued various commercial “radiotelephone operator” licenses and permits to qualified applicants. These allow them to install service, and maintain voice-only radio transmitter systems for use on ships and aircraft. (Until deregulation in the 1990s they were also required for commercial domestic radio and television broadcast systems. Because of treaty obligations they are still required for engineers of international shortwave broadcast stations.) The certificate currently issued is the General radiotelephone operator license.
The word phone has a long precedent beginning with early US wireless voice systems. The term means voice as opposed to telegraph or Morse Code. This would include systems fitting into the category of two-way radio or one-way voice broadcasts such as coastal maritime weather. The term is still popular in the amateur radio community and in US Federal Communications Commission regulations.
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Since 1930s ..........
user8644oxtys6:
это и так понятно, предложение как составить?
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