capable professional walkie-talkie , a popular inexpensive radio from China Walkie-talkies are widely used in any setting where portable radio communications are necessary, including business,
public safety, military, outdoor recreation, and the like, and devices are available at numerous price points from inexpensive analog units sold as toys up to ruggedized (i.e.
waterproof or
intrinsically safe) analog and digital units for use on boats or in heavy industry. Most countries allow the sale of walkie-talkies for, at least, business,
marine communications, and some limited personal uses such as
CB radio, as well as for amateur radio designs. 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
ultra high frequency (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
squelch capabilities such as
CTCSS (analog squelch) and
DCS (digital squelch) (often marketed as "privacy codes") to inexpensive radios, as well as voice scrambling and trunking capabilities. Some units (especially amateur HTs) also include
dual-tone multi-frequency keypads for remote operation of various devices such as
repeaters. Some models include
voice-operated switch capability for hands-free operation, as well as the ability to attach external microphones and speakers. 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
amateur radio operators. While converted commercial gear by companies such as Motorola is not uncommon, many companies such as
Yaesu,
Icom, and
Kenwood design models specifically for amateur use. While superficially similar to commercial and personal units (including such things as CTCSS and DCS squelch functions, used primarily to activate amateur radio
repeaters), amateur gear usually has a number of features that are not common to other gear, including: • 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
2 meters or
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, 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.
FRS, Europe's
PMR446 and Australia's
UHF CB) in other countries. While FRS walkie-talkies are also sometimes used as toys because mass-production makes them low in cost, they have proper
superheterodyne receivers and are a useful communication tool for both business and personal use. The boom in licence-free transceivers has, however, been a source of frustration to users of licensed services which are sometimes interfered with. For example, FRS and
GMRS overlap in the United States, resulting in substantial
pirate use of the GMRS frequencies. Use of the GMRS frequencies (USA) requires a license; however most users either disregard this requirement or are unaware. Canada reallocated frequencies for licence-free use due to heavy interference from US GMRS users. The European PMR446 channels fall in the middle of a United States UHF amateur allocation, and the US FRS channels interfere with public safety communications in the United Kingdom. Designs for personal walkie-talkies are in any case tightly regulated, generally requiring non-removable antennas (with a few exceptions such as
CB radio and the United States
MURS allocation) and forbidding modified radios. Most personal walkie-talkies sold are designed to operate in
UHF allocations, and are designed to be very compact, with buttons for changing channels and other settings on the face of the radio and a short, fixed antenna. Most such units are made of heavy, often brightly colored plastic, though some more expensive units have ruggedized metal or plastic cases. Commercial-grade radios are often designed to be used on allocations such as GMRS or MURS (the latter of which has had very little readily available purpose-built equipment). In addition, CB walkie-talkies are available, but less popular due to the propagation characteristics of the 27 MHz band and the general bulkiness of the gear involved. 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;
Garmin's Rino series combine a
GPS receiver in the same package as an FRS/GMRS walkie-talkie (allowing Rino users to transmit digital location data to each other). Some personal radios also include receivers for AM and FM broadcast radio and, where applicable,
NOAA Weather Radio and similar systems broadcasting on the same frequencies. Some designs also allow the sending of text messages and pictures between similarly equipped units. 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
toys such as the Fisher Price Walkie-Talkie for children illustrated in the top image on the right. Prior to the change of
CB radio from
licensed to "permitted by part" (FCC rules Part 95) status, the typical toy walkie-talkie available in
North America was limited to 100 milliwatts of power on transmit and using one or two crystal-controlled channels in the 27
MHz citizens' band using
amplitude modulation (AM) only. Later toy walkie-talkies operated in the 49 MHz band, some with
frequency modulation (FM), shared with cordless phones and baby monitors. The lowest cost devices are very simple electronically (single-frequency,
crystal-controlled, generally based on a simple discrete
transistor circuit where "grown-up" walkie-talkies use
chips), may employ
super regenerative receivers, and may lack even a volume control, but they may nevertheless be elaborately decorated, often superficially resembling more "grown-up" radios such as FRS or public safety gear. Unlike more costly units, low-cost toy walkie-talkies may not have separate microphones and speakers; the receiver's speaker sometimes doubles as a microphone while in transmit mode. 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
Morse code or similar tones to another walkie-talkie operating on the same frequency. Generally the operator depresses the PTT button and taps out a message using a Morse Code
crib sheet attached as a sticker to the radio. However, as Morse Code has fallen out of wide use outside amateur radio circles, some such units either have a grossly simplified code label or no longer provide a sticker at all. In addition,
Family Radio Service UHF radios will sometimes be bought and used as toys, though they are not generally explicitly marketed as such (but see
Hasbro's
ChatNow line, which transmits both voice and digital data on the FRS band). Some
cellular telephone networks offer a push-to-talk handset that allows walkie-talkie-like operation over the cellular network, without dialing a call each time. However, the cellphone provider must be accessible.
Specialized uses grain inspector with RCA TacTec walkie-talkie,
New Orleans, 1976 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
Intrinsically safe walkie-talkies are often required in heavy industrial settings where the radio may be used around flammable vapors. This designation means that the knobs and switches in the radio are engineered to avoid producing sparks as they are operated. == Software emulation ==