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PTT ID
PTT ID, or Push-To-Talk ID, is a generic term for an automatic number identification (ANI)-like system used in two-way radio systems. It provides identification of the transmitting radio over the air, and is commonly used in selective calling/signaling systems, usually in commercial and public safety radio systems. PTT ID features are included in MDC-1200 MDC (Motorola Data Communications), also known as Stat-Alert, MDC-1200 and MDC-600, is a Motorola two-way radio low-speed data system using audio frequency shift keying, (AFSK). MDC-600 uses a 600 baud data rate. MDC-1200 uses a 1,200 baud data ... and other signaling systems. {{Two-way radio Radio technology ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Automatic Number Identification
Automatic number identification (ANI) is a feature of a telecommunications network for automatically determining the origination telephone number on toll calls for billing purposes. Automatic number identification was originally created by the American Telephone and Telegraph Company (AT&T) for long distance service in the Bell System, eliminating the need for telephone operators to manually record calls. Modern ANI has two components: information digits, which identify the class of service, and the calling party billing telephone number. The term is also used to describe the functions of two-way radio selective calling that identify the transmitting user. ANI is distinct from newer caller ID services, such as call display, which are solely for informing a subscriber. Toll-free telephone numbers Modern toll-free telephone numbers, which generate itemized billing of all calls received instead of relying on the special fixed-rate trunks of the Bell System's original Inward WAT ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Two-way Radio
A two-way radio is a radio that can both transmit and receive radio waves (a transceiver), unlike a broadcast receiver which only receives content. It is an audio (sound) transceiver, a transmitter and receiver in one unit, used for bidirectional person-to-person voice communication with other users with similar radios. Two-way radios are available in stationary ( base station), mobile (installed in vehicles), and hand-held portable models. Hand-held two-way radios are often called walkie-talkies, handie-talkies or hand-helds. Two-way radios are used by groups of geographically separated people who need to keep in continuous voice communication, such as aircraft pilots and air traffic controllers, ship captains and harbormasters, emergency services personnel like firefighters, police officers, and ambulance paramedics, taxi and delivery services, soldiers and military units, fast food and warehouse employees, and radio amateurs. Two-way radio systems may use a single radio c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Selective Calling
In a conventional, analog two-way radio system, a standard radio has ''noise squelch'' or ''carrier squelch'', which allows a radio to receive all transmissions. Selective calling is used to address a subset of all two-way radios on a single radio frequency channel. Where more than one user is on the same channel (co-channel users), selective calling can address a subset of all receivers or can direct a call to a single radio. Selective calling features fit into two major categories—''individual calling'' and ''group calling''. Individual calls generally have longer time-constants: it takes more air-time to call an individual radio unit than to call a large group of radios. Selective calling is akin to the use of a lock on a door. A radio with carrier squelch is unlocked and will let any signal in. Selective calling locks out all signals except ones with the correct "key", in this case a specific digital code. Selective calling systems can overlap; a radio may have (group call) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MDC-1200
MDC (Motorola Data Communications), also known as Stat-Alert, MDC-1200 and MDC-600, is a Motorola two-way radio low-speed data system using audio frequency shift keying, (AFSK). MDC-600 uses a 600 baud data rate. MDC-1200 uses a 1,200 baud data rate. Systems employ either one of the two baud rates. Mark and space tones are 1,200 Hz and 1,800 Hz. The data are sent in bursts over the radio system's voice channel. MDC signaling includes a number of features: unit ID, status buttons, emergency button, selective inhibit, radio check, and selective calling. These features are programmable and could be used in any combination desired by the user. They are typically incorporated in high-end analog FM commercial and public safety radios made by Motorola and other manufacturers. In addition to Motorola, at least two other companies make compatible base station decoders for MDC-1200. Motorola radios with MDC options have an option allowing the radio to filter out data bursts from th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
