radio telephone system
41Telephone number — A telephone number or phone number is a sequence of digits used to call from one telephone line to another in a public switched telephone network. When telephone numbers were invented, they were short as few as one, two or three digits and were… …
42Telephone hybrid — A telephone hybrid is a relatively simple electronic device used to connect telephone line to studio audio circuits. These are normally used in radio stations (and sometimes TV stations and broadcast networks) to connect callers into the airchain …
43Radio communications during the September 11 attacks — This article reviews some of the details of radio communications at the September 11, 2001 World Trade Center attacks. [The purpose of revealing the operational details in this article is to allow operators of other communications networks and… …
44radio — /ray dee oh /, n., pl. radios, adj., v., radioed, radioing. n. 1. wireless telegraphy or telephony: speeches broadcast by radio. 2. an apparatus for receiving or transmitting radio broadcasts. 3. a message transmitted by radio. adj. 4. pertaining …
45Telephone switchboard — PBX switchboard, 1975 A switchboard (also called a manual exchange) was a device used to connect a group of telephones manually to one another or to an outside connection, within and between telephone exchanges or private branch exchanges (PBXs) …
46Radio broadcasting — Long wave radio broadcasting station, Motala, Sweden …
47Telephone numbers in China — Country Code: +86 International Call Prefix: 00 Trunk Prefix: 0 The Chinese Telephone Code Plan is the way to group telephone numbers of Mainland China. Land lines and mobile phones follow different systems: land lines use area codes, while… …
48Radio transmitter design — In plate modulation systems the voltage delivered to the stage is changed. As the power output available is a function of the supply voltage, the output power is modulated. This can be done using a transformer to alter the anode (plate) voltage.… …
49Radio-controlled helicopter — Nitro powered Align T Rex 600 NSP Electric powered Venom Ai …
50Radio teleswitch — The Radio Teleswitch Service (RTS) has its origins in the energy management projects initiated in the United Kingdom by the Electricity Council in the early 1980s. Three projects investigated the feasibility of using the telephone network, the… …
