FRS (Family Radio Service)

A very low power, short-range two-way radio service in the 460 MHz band. (Cingular)

The Family Radio Service is an improved walkie talkie system authorized in the United States. This personal radio service uses frequencies in the UHF band, and so does not suffer the interference effects found on Citizens Band (CB) at 27 MHz, or the 49 MHz band also used by cordless phones, toys, and baby monitors. FRS uses FM instead of AM, and has a greater reliable range than license-free radios operating in the CB or 49 MHz bands.

Although initially proposed by Radio Shack for use by families, FRS has also seen significant adoption by business interests, as an unlicensed, low-cost alternative to the business band.

FRS radios are limited to 500 milliwatts in the U.S., according to FCC regulations. Channels 1 to 7 are shared with GMRS, the General Mobile Radio Service. A license is required for those channels only if the power output is over FRS limits, up to GMRS limits. Unlike Citizens' Band (CB) radios, FRS radios frequently have provisions for using sub-audible tone squelch (CTCSS) codes, filtering out unwanted chatter from other users on the same frequency. These codes are sometimes called "privacy codes", but they offer no real deterrence against eavesdropping.

The use of repeaters and interconnects to the telephone network are prohibited, unlike in GMRS. FRS radios must use only permanently-attached antennas, which restricts the range of communication but also limits interference to other users.

FRS manufacturers generally claim an effective range of 3 km (2 miles), but actual performance varies widely. The presence of large metal buildings can reduce range, but hobbyists have found that under exceptional conditions (hill-top to hill-top) communication is possible over 50 km (30 miles) or more. Under normal conditions, FRS generally has an effective range of approximately 1.5 km (1 mile).

Recently, the personal electronics industry has begun producing 22-channel FRS/GMRS hybrid radios. Use of the GMRS channels on such radios requires a license from the FCC.

FRS radios have been approved for use in Canada since April 2000. The revised technical standard RSS 210 has essentially the same technical requirements as in the United States. Since September 2004 low-power GMRS radios and dual-standard GMRS/FRS radios have also been approved for use in Canada, giving additional channels.

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

FRS is an American description. In Europe, a similar service with the same sort of licensing restriction is PMR446 having eight channels in the 446MHz range. Thus one cannot legally use the FRS radio in Europe or PMR446 in the USA. The 446 MHZ band is allocated to amateur radio in the United States, so in principle a licensed amateur operator could use non-FCC-type-accepted PMR446 radios in the US in compliance with the rules for amateur radio operation. In Great Britain FRS frequencies are used for Fire brigade communications and this sometimes causes problems when FRS equipment is illegally imported from the USA and used (usually inadvertently) by members of the public.

Dual-mode GMRS/FRS equipment is approved in Brazil and most South American countries. Portable radios are heavily used in private communications, specially by security staff in nightclubs and shopping centers, but also in private parking/maintenance/delivery services, etc.

(Wikipedia)