Family Radio Service

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.

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.

FRS radios use narrow-band frequency modulation (NBFM) with a maximum deviation of 2.5 kilohertz. The channels are spaced at 25 kilohertz intervals, with all frequencies ending in 2.5 or 7.5 kHz.

FRS radios are limited to 500 milliwatts according to U.S. Federal Communications Commission (FCC) regulations. Channels 1 to 7 are shared with low-power interstitial channels of General Mobile Radio Service (GMRS). A license is required for those channels if the power output is over FRS limits.

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