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The Family Radio Service (FRS) is an improved walkie-talkie radio system authorized in the United States since 1996. This personal radio service uses channelized frequencies around 462 and 467 MHz in the ultra high frequency (UHF) band. It does not suffer the interference effects found on citizens' band (CB) at 27 MHz, or the 49 MHz band also used by cordless telephones, toys, and baby monitors. FRS uses frequency modulation (FM) instead of amplitude modulation (AM). Since the UHF band has different radio propagation characteristics, short-range use of FRS may be more predictable than the more powerful license-free radios operating in the HF CB band.

Initially proposed by RadioShack in 1994 for use by families, FRS has also seen significant adoption by business interests, as an unlicensed, low-cost alternative to the business band. New rules issued by the FCC in May 2017 clarify and simplify the overlap between FRS and GMRS radio services.

Worldwide, a number of similar personal radio services exist; these share the characteristics of low power, operation in the UHF (or upper VHF) band using FM, and simplified or no end-user licenses. Exact frequency allocations differ, so equipment legal to operate in one country may cause unacceptable interference in another.


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Technical information

FRS radios use narrow-band frequency modulation (NBFM) with a maximum deviation of 2.5 kilohertz. The channels are spaced at 12.5 kilohertz intervals.

After May 18, 2017, FRS radios are limited to 2 Watts on channel 1-7 and channels 15-22. Previously, FRS radios were limited to 500 milliwatts. Channels 1 to 7 are shared with low-power interstitial channels of General Mobile Radio Service (GMRS).

FRS radios frequently have provisions for using sub-audible tone squelch (CTCSS and DCS) codes, filtering out unwanted chatter from other users on the same frequency. Although these codes are sometimes called "privacy codes" or "private line codes" (PL codes), they offer no protection from eavesdropping and are only intended to help reduce unwanted audio when sharing busy channels. Tone codes also do nothing to prevent desired transmissions from being swamped by stronger signals having a different code.

All equipment used on FRS must be type accepted according to FCC regulations. Radios are not type-accepted for use in this service if they exceed limits on power output, have a detachable antenna, allow for unauthorized selection of transmitting frequencies outside of the 22 frequencies designated for FRS, or for other reasons. After December 2017, the FCC no longer accepts applications to certify hand-held FRS units providing for transmission in any other radio band.

FRS radios must use only permanently attached antennas,; there are also table-top FRS "base station" radios that have whip antennas. This limitation intentionally restricts the range of communications, allowing greatest use of the available channels by the community. The use of duplex radio repeaters and interconnects to the telephone network are prohibited under FRS rules.

FRS manufacturers generally claim exaggerated range. The presence of large buildings, trees, etc., will reduce range. Under exceptional conditions, (such as hilltop to hilltop, or over open water) communication is possible at 60 km (37 mi) or more, but that is rare. Under normal conditions, with line of sight blocked by a few buildings or trees, FRS has an actual range of about 0.5 to 1.5 km (0.3 to 1 mile).


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FRS/GMRS hybrid radios

In May 2017, the FCC significantly revised the rules for combination FRS/GMRS radios. Combination radios will be permitted to radiate 2 watts on all channels, and all FRS channels are now considered shared with the GMRS service. Operation over 2 watts, or operation on GMRS repeater input channels, will still required GMRS licensing. The FCC will not certify combination FRS/GMRS radios that exceed the current power limits for the FRS service.

Hybrid FRS/GMRS consumer radios have been introduced that have 22 channels. Before May 2017, radios had been certified for unlicensed operation on the 7 FRS frequencies, channels 8-14, under FRS rules.

Prior to the 2017 revision, FCC rules required a GMRS license to operate on channels 1-7 using more than 0.5 watts. Many hybrid radios have an ERP that is lower than 0.5 watts on channels 1-7, or can be set by the user to operate at low power on these channels. This allows hybrid radios to be used under the license-free FRS rules if the ERP is less than 0.5 watts and the unit is certified for FRS operation on these frequencies. Beginning September 28, 2017, FRS operation is permitted at up to 2 watts on these channels.

Interference to licensed services may be investigated by the FCC.

Channels 8-14, formerly exclusive to FRS, since September 28, 2017 can be used by GMRS at 0.5 watts. Channels 15-22, formerly reserved exclusively for GMRS, can be used at up to 2 watts in the FRS.

Effective September 30, 2019, it becomes unlawful in the USA to import, manufacture, sell or offer to sell radio equipment capable of operating under both GMRS and FRS.


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List of FRS channels compared to GMRS

  • EIRP = Effective Isotropic Radiated Power
  • GMRS has other exclusive channels
  • FRS channels 8-14 are exclusively FRS with no detachable antenna such as found on GMRS equipment. No FRS unit shall exceed .5 watt (EIRP) Effective Isotropic Radiated Power on channels 8-14. FRS Channels 15-22 are shared with GMRS also under 2 watt EIRP limit. However, if the device includes any of the following channels (467.5500, 467.5750, 467.6000, 467.6250, 467.6500, 467.6750, 467.7000, and 467.7250 MHz) a GMRS license is required. The only benefit of a GMRS license is the ability to use a repeater and communicate longer distances.

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FRS radios in other countries

Personal UHF radio services similar to the American FRS exist in other countries, although since technical standards and frequency bands will differ, usually FCC-approved FRS equipment may not be used in other jurisdictions.

Canada

American-standard FRS radios have been approved for use in Canada since April 2000. As of 2016, only low-power (2W ERP), half duplex GMRS operation is permitted, but a license is not required. Repeater and high-power operations are not permitted. This allows the use of dual-mode FRS/GMRS walkie-talkies, but precludes the use of higher-powered devices designed for vehicle and base-station purposes.

Mexico

Since tourists often bring their FRS radios with them, and since trade between the U.S., Canada, and Mexico is of great value to all three countries, the Mexican Secretary of Communication and Transportation has authorized use of the FRS frequencies and equipment similar to that in the US. However, dual-mode FRS/GMRS equipment is not approved in Mexico, so caution should be exercised in operating hybrid FRS/GMRS devices purchased elsewhere.

South America

Dual-mode GMRS/FRS equipment is also approved in Brazil (GMRS only in simplex mode, GMRS frequencies 462.550, 467.550, 462.725, 467.725 are not allowed) and most other South American countries. Portable radios are heavily used in private communications, mainly by security staff in nightclubs and malls, but also in private parking, maintenance, and delivery services.


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Other personal radio services

Many personal radio services similar to the FRS exist around the world. Because radio spectrum allocation varies around the world, a personal radio service device may not be usable outside its original area of purchase. FRS equipment may not be legally permitted in other countries because it uses frequencies allocated to services such as police or fire; however, many countries have equivalents to the FRS.




See also

  • General Mobile Radio Service
  • Multi-Use Radio Service
  • PMR446
  • Continuous Tone-Coded Squelch System (CTCSS)



References




External links

  • FRS Radios in Mexico
  • Industry Canada discussion on the approval of FRS in Canada
  • The situation of License Free Radio System in Japan

Source of the article : Wikipedia

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