There have been several companies in recent years that have been developing “high-power” radios marketed as family or recreation communication devices sold in department stores as impulse buys. The devices have a range of a few miles, are powered by AA batteries or a rechargeable battery pack, and are surprisingly simple and easy to use.
FRS and GMRS are the technologies behind these radios. Even though they often sit right next to each other on the shelf and are packaged similarly, these two types of radios are very different when it comes to capabilities and operating rules.
In 1996, the FCC approved Family Radio Service for unlicensed use. It operates between 462 and 467 MHz, and is sometimes referred to as the “UHF Citizens Band.” This is not an 802.11 radio, but is governed by FCC Part 95, Personal Radio Services . GMRS and FRS share some channels, but FRS radios can only output 500mW at most. FRS radios typically have a range of two miles. Antennas and amplifiers cannot be legally added to FRS radios because they come with fixed antennas.
GMRS stations can communicate with FRS radios through channels 1 through 7 which overlap with GMRS. You should use channels 8 through 14 if you only want to talk to other FRS radios to avoid possible interference with low band GMRS users. The full list of FRS and GMRS frequencies can be found in Table 1-1.
GMRS stands for General Mobile Radio Service, also known as “Class A Citizens Band.” This service is covered by FCC Part 95, but requires a license to operate. The cost of a personal license as of this writing is $75 and can be obtained online at http://wireless.fcc.gov/uls/.
GMRS handhelds are capable of putting out up to 5 Watts of power, although 4-Watt units are more common. When communicating on FRS channels, fixed-base stations are restricted to 5 Watts, even though they can use up to 15 Watts on most frequencies. Stations that transmit on repeater channels can transmit at a maximum of 50 Watts. Stations and repeaters can only transmit on the lower “462” frequencies, while handhelds can transmit on any GMRS frequency. See Table 1-1 for a complete list of FRS and GMRS frequencies. Antennas on GMRS gear can be removed, enabling a handheld to be used with a car mount or stationary antenna. Thanks to its ability to use repeaters, GMRS can be used for long-distance communication.
|Lower frequency||Upper frequency||Purpose|
|462.5625||—||FRS channel 1, GMRS “5625”|
|462.5875||—||FRS channel 2, GMRS “5875”|
|462.6125||—||FRS channel 3, GMRS “6125”|
|462.6375||—||FRS channel 4, GMRS “6375”|
|462.6625||—||FRS channel 5, GMRS “6625”|
|462.6875||—||FRS channel 6, GMRS “6875”|
|462.7125||—||FRS channel 7, GMRS “7125”|
|467.5625||—||FRS channel 8|
|467.5875||—||FRS channel 9|
|467.6125||—||FRS channel 10|
|467.6375||—||FRS channel 11|
|467.6625||—||FRS channel 12|
|467.6875||—||FRS channel 13|
|467.7125||—||FRS channel 14|
|Channel||Type||Frequency||FRSPower / Bandwidth||GMRSPower / Bandwidth|
|1||FRS/GMRS||462.5625||2W / 12.5kHz||5W / 25kHz*|
|2||FRS/GMRS||462.5875||2W / 12.5kHz||5W / 25kHz*|
|3||FRS/GMRS||462.6125||2W / 12.5kHz||5W / 25kHz*|
|4||FRS/GMRS||462.6375||2W / 12.5kHz||5W / 25kHz*|
|5||FRS/GMRS||462.6625||2W / 12.5kHz||5W / 25kHz*|
|6||FRS/GMRS||462.6875||2W / 12.5kHz||5W / 25kHz*|
|7||FRS/GMRS||462.7125||2W / 12.5kHz||5W / 25kHz*|
|8||FRS/GMRS||467.5625||0.5W / 12.5kHz||0.5W / 12.5kHz|
|9||FRS/GMRS||467.5875||0.5W / 12.5kHz||0.5W / 12.5kHz|
|10||FRS/GMRS||467.6125||0.5W / 12.5kHz||0.5W / 12.5kHz|
|11||FRS/GMRS||467.6375||0.5W / 12.5kHz||0.5W / 12.5kHz|
|12||FRS/GMRS||467.6625||0.5W / 12.5kHz||0.5W / 12.5kHz|
|13||FRS/GMRS||467.6875||0.5W / 12.5kHz||0.5W / 12.5kHz|
|14||FRS/GMRS||467.7125||0.5W / 12.5kHz||0.5W / 12.5kHz|
|15||FRS/GMRS||462.5500||2W / 12.5kHz||50W / 25kHz*|
|16||FRS/GMRS||462.5750||2W / 12.5kHz||50W / 25kHz*|
|17||FRS/GMRS||462.6000||2W / 12.5kHz||50W / 25kHz*|
|18||FRS/GMRS||462.6250||2W / 12.5kHz||50W / 25kHz*|
|19||FRS/GMRS||462.6500||2W / 12.5kHz||50W / 25kHz*|
|20||FRS/GMRS||462.6750||2W / 12.5kHz||50W / 25kHz*|
|21||FRS/GMRS||462.7000||2W / 12.5kHz||50W / 25kHz*|
|22||FRS/GMRS||462.7250||2W / 12.5kHz||50W / 25kHz*|
|RPT15||GMRS||467.5500||–||50W / 25kHz*|
|RPT16||GMRS||467.5750||–||50W / 25kHz*|
|RPT17||GMRS||467.6000||–||50W / 25kHz*|
|RPT18||GMRS||467.6250||–||50W / 25kHz*|
|RPT19||GMRS||467.6500||–||50W / 25kHz*|
|RPT20||GMRS||467.6750||–||50W / 25kHz*|
|PRT21||GMRS||467.7000||–||50W / 25kHz*|
|RPT22||GMRS||467.7250||–||50W / 25kHz*|
In general, handheld GMRS units communicate on lower frequencies when possible, and transmit on higher frequencies (while listening 5 MHz lower) to talk to a repeater. From the “462” side, listeners can hear traffic both from handhelds and from the repeater. Avoid unnecessary interference with other GMRS users by using low frequencies and low power settings whenever possible. Repeaters should only be used when no other means of communication are available.
The best way to increase your range is to increase your altitude rather than use higher power radios. When an antenna is high in the air, even with limited power, UHF radios can reach much further. Part 95 limits “small control stations” to antennas no higher than 20 feet above the structure to which they are mounted. When transmitting with your FRS or GMRS radio, find high ground. Your available range can be extended by many, many miles when this happens. You can significantly increase the range of a GMRS radio by attaching it to a tall antenna.
Even though these radios are half-duplex and allow limited data transmission, they can be useful in a variety of situations. Depending on the requirements, you may find them far more useful than mobile phones when fine-tuning an 802.11 link over long distances. FRS and GMRS can work considerably better than phones when you are far from a city, particularly on hills and mountains. You can’t connect a radio to a telephone patch on either FRS or GMRS; this is prohibited.
The best FRS radio is one that is going to work for you in your circumstances. There are a lot of variables to consider and you might not be able to find one that will work for you in all situations. A radio that works great in the city may not work as well in the mountains.
You may find that the people you want to communicate with may not be able to use the same radio frequency. There are a lot of options available and you should consider what will work best for your situation.