Walkie-talkie
A walkie-talkie, more formally known as a handheld transceiver (HT), is a hand-held, portable,
Typical walkie-talkies resemble a
Some units have additional features such as sending calls, call reception with vibration alarm, keypad locking, and a stopwatch.[2][3] Smaller walkie-talkies are also very popular among young children.
In line to the
History
Handheld two-way radios were developed by the military from backpack radios carried by a soldier in an infantry squad to keep the squad in contact with their commanders. The first patent owner was possibly the engineer,
The first device to be widely nicknamed a "walkie-talkie" was developed by the US military during World War II, the backpacked
The first handheld walkie-talkie was the AM SCR-536 transceiver from 1941, also made by Motorola, named the Handie-Talkie (HT).[11] The terms are often confused today, but the original walkie-talkie referred to the back mounted model, while the handie-talkie was the device which could be held entirely in the hand. Both devices used vacuum tubes and were powered by high voltage dry cell batteries.
Following World War II,
In the mid-1970s, the United States Marine Corps initiated an effort to develop a squad radio to replace the unsatisfactory helmet-mounted AN/PRR-9 receiver and receiver/transmitter handheld AN/PRT-4 (both developed by the US Army). The AN/PRC-68, first produced in 1976 by Magnavox, was issued to the Marines in the 1980s, and was adopted by the US Army as well.
The abbreviation HT, derived from Motorola's "Handie-Talkie" trademark, is commonly used to refer to portable handheld
Contemporary use
Walkie-talkies are widely used in any setting where portable radio communications are necessary, including business,
Walkie-talkies for public safety, and commercial and industrial uses may be part of trunked radio systems, which dynamically allocate radio channels for more efficient use of the limited radio spectrum. Such systems always work with a base station that acts as a repeater and controller, although individual handsets and mobiles may have a mode that bypasses the base station.
Walkie-talkies, thanks to increasing use of miniaturized electronics, can be made very small, with some personal two-way UHF radio models being smaller than a deck of cards (though VHF and HF units can be substantially larger due to the need for larger antennas and battery packs). In addition, as costs come down, it is possible to add advanced
Consumer and commercial equipment differ in a number of ways; commercial gear is generally ruggedized, with metal cases, and often has only a few specific frequencies programmed into it (often, though not always, with a computer or other outside programming device; older units can simply swap crystals), since a given business or public safety agent must often abide by a specific frequency allocation. Consumer gear, on the other hand, is generally made to be small, lightweight, and capable of accessing any channel within the specified band, not just a subset of assigned channels.
Military
Military organizations use handheld radios for a variety of purposes. Modern units such as the AN/PRC-148 Multiband Inter/Intra Team Radio (MBITR) can communicate on a variety of bands and modulation schemes and include encryption capabilities.
Amateur radio
Walkie-talkies (also known as HTs or "handheld transceivers") are widely used among
- Wide-band receivers, often including radio scanner functionality, for listening to non-amateur radio bands.
- Multiple bands; while some operate only on specific bands such as 70 cm, others support several UHF and VHF amateur allocations available to the user.
- Since amateur allocations usually are not channelized, the user can dial in any frequency desired in the authorized band (whereas commercial HTs usually only allow the user to tune the radio into a number of already programmed channels). This is known as "variable frequency operation (VFO) mode.
- Multiple modulation schemes: a few amateur HTs may allow modulation modes other than FM, including AM, SSB, and CW,[14][15] and digital modes such as radioteletype or PSK31. Some may have TNCs built in to support packet radio data transmission without additional hardware.
Digital voice modes are available on some amateur HTs. For example, newer additions to the Amateur Radio service are Next Generation Digital Narrowband (NXDN) and Digital Smart Technology for Amateur Radio or D-STAR. Handheld radios with these technologies have several advanced features, including narrower bandwidth, simultaneous voice and messaging, GPS position reporting, and callsign routed radio calls over a wide-ranging international network.
As mentioned, commercial walkie-talkies can sometimes be reprogrammed to operate on amateur frequencies. Amateur radio operators may do this for cost reasons or due to the fact that Public Safety grade commercial gear is more solidly constructed and better designed than purpose-built amateur gear that is built to a price.
Personal use
The personal walkie-talkie has become popular also because of licence-free services (such as the U.S.
Most personal walkie-talkies sold are designed to operate in
Personal walkie-talkies are generally designed to give easy access to all available channels (and, if supplied, squelch codes) within the device's specified allocation.
Personal two-way radios are also sometimes combined with other electronic devices;
While jobsite and government radios are often rated in power output, consumer radios are frequently and controversially rated in mile or kilometer ratings. Because of the line of sight propagation of UHF signals, experienced users consider such ratings to be wildly exaggerated, and some manufacturers have begun printing range ratings on the package based on terrain as opposed to simple power output.
While the bulk of personal walkie-talkie traffic is in the 27 MHz and 400–500 MHz area of the UHF spectrum, there are some units that use the "Part 15" 49 MHz band (shared with cordless phones, baby monitors, and similar devices) as well as the "Part 15" 900 MHz band; in the US at least, units in these bands do not require licenses as long as they adhere to FCC Part 15 power output rules. A company called TriSquare is, as of July 2007, marketing a series of walkie-talkies in the United States, based on frequency-hopping spread spectrum technology operating in this frequency range under the name eXRS (eXtreme Radio Service—despite the name, a proprietary design, not an official allocation of the US FCC). The spread-spectrum scheme used in eXRS radios allows up to 10 billion virtual "channels" and ensures private communications between two or more units.
Recreation
Low-power versions, exempt from licence requirements, are also popular children's
An unusual feature, common on children's walkie-talkies but seldom available otherwise even on amateur models, is a "code key", that is, a button allowing the operator to transmit
In addition,
Smartphone apps and connected devices
A variety of
Applications on the market that offer this walkie-talkie style interaction for audio include Hytera,[16] Voxer, Zello, Orion Labs, Motorola Wave, and HeyTell, among others.[17]
Other smartphone-based walkie-talkie products are made by companies like goTenna, Fantom Dynamics and BearTooth, and offer a radio interface.[citation needed] Unlike mobile data dependent applications, these products work by pairing to an app on the user's smartphone and working over a radio interface.[18]
Specialized uses
In addition to land mobile use, waterproof walkie talkie designs are also used for marine VHF and aviation communications, especially on smaller boats and ultralight aircraft where mounting a fixed radio might be impractical or expensive. Often such units will have switches to provide quick access to emergency and information channels. They are also used in recreational UTVs to coordinate logistics, keep riders out of the dust and are usually connected to an intercom and headsets
Accessories
There are various types of accessories available for walkie-talkies such as rechargeable batteries, drop-in rechargers, multi-unit rechargers for charging as many as six units at a time, and an audio accessory jack that can be used for headsets or speaker microphones. Newer models allow the connection to wireless headsets via Bluetooth. Some models also came up with the wifi integration such as Motorola XIRP 8600i series.[19]
See also
- Mobile radio telephone
- MOTO Talk
- Serval project
- Signal Corps Radio
- Survival radio
- Tank phone
- Vehicular communication systems
References
Footnotes
- ISBN 978-1-85109-732-6.
- ^ Stabo Freecomm 600
- ^ Stabo Freecomm 650
- ^ patent number 22972, Government Patent Office - 1936
- ^ Government Patent Office News - 1936, p.194 (in pdf page 14) patent number 22972 Urządzenie do szybkiego nawiązywania łączności radiotelegraficznej lub radiotelefonicznej. A device for a quick connection establishing via radiotelegraphy or radiotelephony
- ^ http://www.telecomhall.ca/tour/inventors/2006/donald_l_hings/WalkieTalkie.pdf?sourceid=navclient&ie=UTF-8&rls=GGLJ,GGLJ:2006-10,GGLJ:en&q=Donald+L.+Hings+ Archived 2020-09-23 at the Wayback Machine. THE VANCOUVER SUN, Friday August 17, 2001 Walkie-Talkie Inventor Receives Order of Canada
- ^ "CBC.ca - The Greatest Canadian Invention". CBC News. Archived from the original on June 29, 2007.
- ^ "TM-11296 - Radio set AN/PRC-6" (PDF). radiomanual.info. Dept. of the Army. Retrieved 13 January 2017.
- Lemelson-MIT Program. Archived from the originalon 2019-11-06. Retrieved 2018-10-11.
- ^ Niesel, John. "The SCR-300 Backpack Radio". warfarehistorynetwork.com. Sovereign Media. Retrieved 28 December 2018.
- ^ Wolinsky, Howard (2003-09-25). "Riding Radio Waves For 75 Years, Motorola Milestones". Chicago Sun Times. Retrieved 23 March 2012.
- ^ "Radio set AN/PCR-6" (PDF). VIRhistory.com. Retrieved 13 January 2017.
- OCLC 48123449.
- ^ http://www.rigpix.com/tokyohypower/ht750.htm Tokyo HyPower HT750
- ^ http://www.rigpix.com/mizuho/mizuho_mx2.htm Mizuho MX2
- ^ Bruno Ortiz Bisso (May 31, 2021). "Hytera Launches PoC Walkie Talkie PNC370". El Comercio.
- ^ Pogue, David (5 September 2012). "Smartphone? Presto! 2-Way Radio". The New York Times. Retrieved 3 December 2012.
- ^ Anderson, Sophie (September 2020). "Best Walkie Talkie Apps". Walkie Talkie Guide. Retrieved 26 May 2021.
- ^ https://qcsolution.in/product/motorola-xir-p8600i-radio/
Notations
- Onslow, David. "Two-Way Radio Success: How to Choose Two-Way Radios, Commercial Intercoms, and Other Wireless Communication Devices for Your Business". IntercomsOnline.com. Retrieved 2008-10-24.
Further reading
- Dunlap, Orrin E., Jr. Marconi: The man and his wireless. (Arno Press., New York: 1971)
- Harlow, Alvin F., Old Waves and New Wires: The History of the Telegraph, Telephone, and Wireless. (Appleton-Century Co., New York: 1936)
- Herrick, Clyde N., Radidselopments in Telecommunications 2nd Ed., (Prentice Hall Inc., New Jersey: 1977)
- Martin, James. The Wired Society. (Prentice Hall Inc., New Jersey: 1978)
- Silver, H. Ward. Two-Way Radios and Scanners for Dummies. (Wiley Publishing, Hoboken, NH, 2005, ISBN 978-0-7645-9582-0)