FRS and MURS Radios

Family Radio Service (FRS) Frequencies

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 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 phones, 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 license-free radios operating in the HF CB band.

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.

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

Unlike Citizens' Band (CB) radios, 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 share busy channels. Tone codes also do nothing to prevent desired transmissions from being swamped by stronger signals having a different code.

FRS stations on channels 1 through 7 may communicate with GMRS stations on those shared channels; the GMRS stations may use up to 5 watts of power, while the FRS stations are restricted to 0.5 watts.

The use of duplex radio repeaters and interconnects to the telephone network are prohibited under FRS rules, unlike GMRS which allows repeaters, and unlike the Amateur Radio Service. FRS radios must use only permanently-attached antennas. This limitation intentionally restricts the range of communications, allowing greatest use of the available channels.

FRS manufacturers generally claim exaggerated range. The presence of large buildings, trees, etc., will reduce range. Under exceptional conditions, (such as hill-top to hill-top) communication is possible over 60 km (40 miles) or more, but that is rare. Normal conditions, with line-of-sight blocked by a few buildings or trees, mean FRS has an actual range of 0.5 to 1.5 km (1/3 to 1 mile).

(In my opinion, FRS are good for very short range unless you use other FRS radio operators to relay messages. Good for in buildings or local security needs in the SHTF. Unsecure radio system)

List of FRS channels

Some clubs have recommended FRS Channel 1 as a national emergency/calling channel, such as REACT International, Inc. and the National SOS Radio Network.

Channel 2 is typically used by geocaching groups when trying to connect with other geocachers.

Multi-use radio service (MURS)

(Less crowded and better range than FRS makes this a better system for internal communications. Still good to have FRS to monitor and talk to others in the SHTF, no license required)

In the United States, the Multi-Use Radio Service (MURS) is a two-way radio service consisting of five frequencies in the VHF spectrum regulated by Title 47 of the CFR (Code of Federal Regulations) Part 95. Established by the U.S. Federal Communications Commission in the fall of 2000, MURS created a radio service allowing for "licensed by rule" or "permitted by part" (Part 95) operation (rather than permitted by individual license), with a power limit of 2 watts, four times that of FRS radio. In the fall of 2002, the FCC further amended the MURS rules; these rule modifications included changing the 2 watt power limitation to be based on Transmitter Power Output (TPO), rather than Effective Radiated Power (ERP), so there is no longer an ERP limit with MURS, and external gain antennas may be utilized. The FCC formally defines MURS as "a private, two-way, short-distance voice or data communications service for personal or business activities of the general public." MURS stations may not be connected to the public telephone network, may not be used for store and forward operations, and radio repeaters are not permitted.MURS comprises the following five frequencies:

Because previous business band licensees who have maintained their active license remain grandfathered with their existing operating privileges, it is possible to find repeaters or other operations not authorized by Part 95 taking place. These are not necessarily illegal. If legal, such operations may enjoy primary status on their licensed frequency and as such are legally protected from harmful interference by MURS users.

TWO - WAY COMMUNICATIONS

Disaster planning should include using two-way communications. Anything said on a radio is not secure. Keep all transmissions short! Instead of "cute handles" use false names. Example; Bob could always be called Jim on the radio. Anybody listening would assume Jim is on the radio. If available, use the "automatic roger" feature that sends a "beep" at the end of each transmission. Request repeats only if transmission was not fully understood.

Use a prearranged phrase that is said at the end of the message, such as; " Good day! ". If that phrase IS NOT said, ( or the WRONG phrase is said), then that could indicate trouble without alerting people outside your group. Do not call back and ask if they are okay. Instead ask for a repeat, like you did not understand their last transmission. If the phrase is omitted again take pre-planned action.

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