The
Family Radio Service is an improved walkie talkie system
authorized in the United States since 1996. This personal radio
service uses frequencies in the ultra high frequency (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 frequency
modulation (FM) instead of amplitude modulation (AM), and has a
greater reliable range than license-free radios operating in the
CB or 49 MHz bands.Initially
proposed by Radio Shack 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.
Contents
- Technical information
- Similar services in other
countries
- List of channels
- List of license-free personal
radio services worldwide
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Technical information
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. Though these codes are sometimes
called "privacy codes", they offer no protection from
eavesdropping and are only intended to help share busy channels.
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, like
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.
Similar services in other countries
Services similar to the American FRS
exist in other countries, although since technical standards and
frequency bands may differ, usually FCC-approved FRS equipment
may not be used in other jurisdictions.
American-standard 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 U.S., 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.
In Europe, a personal radio service with
the same sort of licensing restriction is PMR446 having eight
channels in the 446MHz range. One cannot legally use the FRS
radio in Europe or PMR446 in the U.S. 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 U.S. 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 imported from the U.S. and used
without awareness of the consequences 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, especially by security
staff in nightclubs and shopping centers, but also in private
parking, maintenance and delivery services.
A service similar to the American-style
FRS in Hong Kong, Macau and China is also approved by respective
organizations for legal license-free operation. However,
different UHF frequencies with 20 allocated channels near 409
MHz are used. 462 MHz and 446 MHz band are not opened to FRS
service, so European, U.S. and Canada residents are advised not
to use FRS or PMR446 radios for communication when traveling to
the mentioned areas.
List of channels
Channel |
Frequency (MHz) |
1 |
462.5625 |
2 |
462.5875 |
3 |
462.6125 |
4 |
462.6375 |
5 |
462.6625 |
6 |
462.6875 |
7 |
462.7125 |
8 |
467.5625 |
9 |
467.5875 |
10 |
467.6125 |
11 |
467.6375 |
12 |
467.6625 |
13 |
467.6875 |
14 |
467.7125 |