Издательство: | Книга по требованию |
Дата выхода: | июль 2011 |
ISBN: | 978-6-1330-3045-9 |
Объём: | 132 страниц |
Масса: | 221 г |
Размеры(В x Ш x Т), см: | 23 x 16 x 1 |
High Quality Content by WIKIPEDIA articles! In telecommunication, a basic exchange telecommunications radio service (BETRS) is a commercial service that can extend telephone service to rural areas by replacing the local loop with radio communications. In the BETRS, non-government ultra high frequency (UHF) and very high frequency (VHF) common carrier and the private radio service frequencies are shared. Telecommunication is the transmission of messages, over significant distances, for the purpose of communication. In earlier times, telecommunications involved the use of visual signals, such as smoke, semaphore telegraphs, signal flags, and optical heliographs, or audio messages via coded drumbeats, lung-blown horns, or sent by loud whistles, for example.
Данное издание не является оригинальным. Книга печатается по технологии принт-он-деманд после получения заказа.