Motorola Pageboy was the second pager produced by Motorola with individual-unit addressing,[clarification needed] after the lesser-known "Handie-Talkie Radio Pocket Pager" from 1955.[citation needed]
The first pager-like system was used in 1921 by the Detroit Police Department. However, the first pager that we would today recognize as such was Motorola's Pageboy I. [citation needed]
It was introduced in 1964 by the company and could selectively deliver a radio message to a particular individual. It used a high-band VHF frequency (from 150 to 170 MHz), or a UHF frequency (from 464 to 475 MHz), and they ran on a rechargeable 4.4 Volt mercury or 3.6 Volt nickel-cadmium battery (NiCd).[citation needed]
The first implementation of the Pageboy alarm receiver could only give an attention tone, had no display and could not store messages. However, it was portable and notified the wearer that a message had been sent. Later versions of the Pageboy were able to deliver tone & voice.[citation needed]
The Motorola Pageboy used to be very popular with fire brigades as an alarm receiver and, thanks largely to the success of this initial venture, pagers quickly began to replace public announcement systems in hospital and factories. The pager was activated by a 2-tone code, after which a voice message was transmitted. The successor of this device was the Motorola Pageboy II.[citation needed]
An emergency position-indicating radiobeacon (EPIRB) is a type of emergency locator beacon for commercial and recreational boats, a portable, battery-powered radio transmitter used in emergencies to locate boaters in distress and in need of immediate rescue. In the event of an emergency, such as a ship sinking or medical emergency onboard, the transmitter is activated and begins transmitting a continuous 406 MHz distress radio signal, which is used by search-and-rescue teams to quickly locate the emergency and render aid. The signal is detected by satellites operated by an international consortium of rescue services, COSPAS-SARSAT, which can detect emergency beacons anywhere on Earth transmitting on the distress frequency of 406 MHz. The satellites calculate the position or utilize the GPS coordinates of the beacon and quickly passes the information to the appropriate local first responder organization, which performs the search and rescue. As Search and Rescue approach the search areas, they use Direction Finding (DF) equipment to locate the beacon using the 121.5 MHz homing signal, or in newer EPIRBs, the AIS location signal. The basic purpose of this system is to help rescuers find survivors within the so-called "golden day" during which the majority of survivors can usually be saved. The feature distinguishing a modern EPIRB, often called GPIRB, from other types of emergency beacon is that it contains a GPS receiver and broadcasts its position, usually accurate within 100 m (330 ft), to facilitate location. Previous emergency beacons without a GPS can only be localized to within 2 km (1.2 mi) by the COSPAS satellites and relied heavily upon the 121.5 MHz homing signal to pin-point the beacons location as they arrived on scene.
A pager, also known as a beeper or bleeper, is a wireless telecommunications device that receives and displays alphanumeric or voice messages. One-way pagers can only receive messages, while response pagers and two-way pagers can also acknowledge, reply to, and originate messages using an internal transmitter. In Japanese, it was commonly called a pocket bell or pokeberu (ポケベル), which is an example of wasei-eigo.
A radiotelephone, abbreviated RT, is a radio communication system for conducting a conversation; radiotelephony means telephony by radio. It is in contrast to radiotelegraphy, which is radio transmission of telegrams (messages), or television, transmission of moving pictures and sound. The term is related to radio broadcasting, which transmit audio one way to listeners. Radiotelephony refers specifically to two-way radio systems for bidirectional person-to-person voice communication between separated users, such as CB radio or marine radio. In spite of the name, radiotelephony systems are not necessarily connected to or have anything to do with the telephone network, and in some radio services, including GMRS, interconnection is prohibited.
Specific Area Message Encoding (SAME) is a protocol used for framing and classification of broadcasting emergency warning messages. It was developed by the United States National Weather Service for use on its NOAA Weather Radio (NWR) network, and was later adopted by the Federal Communications Commission for the Emergency Alert System, then subsequently by Environment Canada for use on its Weatheradio Canada service. It is also used to set off receivers in Mexico City and surrounding areas as part of the Mexican Seismic Alert System (SASMEX).
NOAA Weather Radio (NWR), also known as NOAA Weather Radio All Hazards, is an automated 24-hour network of VHF FM weather radio stations in the United States that broadcast weather information directly from a nearby National Weather Service office. The routine programming cycle includes local or regional weather forecasts, synopsis, climate summaries or zone/lake/coastal waters forecasts. During severe conditions the cycle is shortened into: hazardous weather outlooks, short-term forecasts, special weather statements or tropical weather summaries. It occasionally broadcasts other non-weather related events such as national security statements, natural disaster information, environmental and public safety statements, civil emergencies, fires, evacuation orders, and other hazards sourced from the Federal Communications Commission's (FCC) Emergency Alert System. NOAA Weather Radio uses automated broadcast technology that allows for the recycling of segments featured in one broadcast cycle into another and more regular updating of segments to each of the transmitters. It also speeds up the warning transmitting process.
A walkie-talkie, more formally known as a handheld transceiver (HT), is a hand-held, portable, two-way radio transceiver. Its development during the Second World War has been variously credited to Donald Hings, radio engineer Alfred J. Gross, Henryk Magnuski and engineering teams at Motorola. First used for infantry, similar designs were created for field artillery and tank units, and after the war, walkie-talkies spread to public safety and eventually commercial and jobsite work.
IS-54 and IS-136 are second-generation (2G) mobile phone systems, known as Digital AMPS (D-AMPS), and most often referred to as TDMA, are a further development of the North American 1G mobile system Advanced Mobile Phone System (AMPS). It was once prevalent throughout the Americas, particularly in the United States and Canada since the first commercial network was deployed in 1993. D-AMPS is considered end-of-life, and existing networks have mostly been replaced by GSM/GPRS or CDMA2000 technologies.
AM stereo is a term given to a series of mutually incompatible techniques for radio broadcasting stereo audio in the AM band in a manner that is compatible with standard AM receivers. There are two main classes of systems: independent sideband (ISB) systems, promoted principally by American broadcast engineer Leonard R. Kahn; and quadrature amplitude modulation (QAM) multiplexing systems.
Professional mobile radio are person-to-person two-way radio voice communications systems which use portable, mobile, base station, and dispatch console radios. PMR systems are based on such standards as MPT-1327, TETRA, APCO 25, and DMR which are designed for dedicated use by specific organizations, or standards such as NXDN intended for general commercial use. These systems are used by police, fire, ambulance, and emergency services, and by commercial firms such as taxis and delivery services. Most systems are half-duplex, in which multiple radios share a common radio channel, and only one can transmit at a time. Transceivers are normally in receive mode, the user presses a push-to-talk button on his microphone when he wants to talk, which turns on his transmitter and turns off his receiver. They use channels in the VHF and UHF bands, giving them a limited range, usually 3 to 20 miles depending on terrain. Output power is typically limited to 4 watts. Repeaters installed on tall buildings, hills or mountain peaks are used to increase the range of systems.
A two-way radio is a radio transceiver, which is used for bidirectional person-to-person voice communication with other users with similar radios, in contrast to a broadcast receiver, which only receives transmissions.
A scanner is a radio receiver that can automatically tune, or scan, two or more discrete frequencies, stopping when it finds a signal on one of them and then continuing to scan other frequencies when the initial transmission ceases.
The 33-centimeter or 900 MHz band is a portion of the UHF radio spectrum internationally allocated to amateur radio on a secondary basis. It ranges from 902 to 928 MHz and is unique to ITU Region 2 (Americas). It is primarily used for very local communications as opposed to bands lower in frequency. However, very high antennas with high gain have shown 33 centimeters can provide good long-range communications almost equal to systems on lower frequencies such as the 70 centimeter band. The band is also used by industrial, scientific, and medical (ISM) equipment, as well as low-powered unlicensed devices. Amateur stations must accept harmful interference caused by ISM users but may receive protection from unlicensed devices.
A weather radio is a specialized radio receiver that is designed to receive a public broadcast service, typically from government-owned radio stations, dedicated to broadcasting weather forecasts and reports on a continual basis, with the routine weather reports being interrupted by emergency weather reports whenever needed. Weather radios are typically equipped with a standby alerting function—if the radio is muted or tuned to another band and a severe weather bulletin is transmitted, it can automatically sound an alarm and/or switch to a pre-tuned weather channel for emergency weather information. Weather radio services may also occasionally broadcast non-weather-related emergency information, such as in the event of a natural disaster, a child abduction alert, or a terrorist attack.
Mobile radio or mobiles refer to wireless communications systems and devices which are based on radio frequencies, and where the path of communications is movable on either end. There are a variety of views about what constitutes mobile equipment. For US licensing purposes, mobiles may include hand-carried,, equipment. An obsolete term is radiophone.
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, 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.
The Motorola Minitor is a portable, analog, receive only, voice pager typically carried by fire, rescue, and EMS personnel to alert of emergencies. The Minitor, slightly smaller than a pack of cigarettes, is carried on a person and usually left in selective call mode. When the unit is activated, the pager sounds a tone alert, followed by an announcement from a dispatcher alerting the user of a situation. After activation, the pager remains in monitor mode much like a scanner, and monitors transmissions on that channel until the unit is reset back into selective call mode either manually, or automatically after a set period of time, depending on programming.
Survival radios are carried by pilots and search and rescue teams to facilitate rescue in an emergency. They are generally designed to transmit on international distress frequencies. Maritime systems have been standardized under the Global Maritime Distress Safety System. Civil and military organisation's utilized different frequencies to communicate and no infringement on either sector would take place. For emergencies involving civilian aircraft, the radio frequency used is VHF 121.5 MHz and for military aircraft incidents, the frequency used is UHF 243 MHz.
The SCR-300 was a portable radio transceiver used by US Signal Corps in World War II. This backpack-mounted unit was the first radio to be nicknamed a "walkie talkie".
Digital mobile radio (DMR) is a digital radio standard for voice and data transmission in non-public radio networks. It was created by the European Telecommunications Standards Institute (ETSI), and is designed to be low-cost and easy to use. DMR, along with P25 phase II and NXDN are the main competitor technologies in achieving 6.25 kHz equivalent bandwidth using the proprietary AMBE+2 vocoder. DMR and P25 II both use two-slot TDMA in a 12.5 kHz channel, while NXDN uses discrete 6.25 kHz channels using frequency division and TETRA uses a four-slot TDMA in a 25 kHz channel.
Motorola Pageboy II was a pager and the successor to the Motorola Pageboy.
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