What are GMRS Radios?
 GMRS radios operate in the 462/467 Mhz frequency range, and was established more than 20 years ago by the FCC to allow non-amateurs (ham radio operators) a way to communicate over longer distances. GMRS radios are often higher power than FRS radios, and offer detachable antennas to allow the user to connect them to more efficient (and better) antenna to obtain longer ranger.
 For the past 20 years, most GMRS radios were similar to the one on the right; usually a reprogrammed public safety radio. Many manufactures have created GMRS only radios, and more recently have created low-price (read: less durable) combination FRS and GMRS radios.
GMRS and FRS FAQ at GMRSWeb
More info on FRS and GMRS at Rick’s Radio Page
Comprehensive write up on GMRS by all2way.com
The Travel Insider has a 3-part article that discusses all aspects of the different radio services.
Great site dedicated to GMRS radios GRMS.net.tc
Be sure to see our New Radios for 2004 page!
Range of GMRS Radios
GMRS radios use the same spectrum as FRS radios. The range of GMRS is generally limited to line-of-sight, that is, if you can see the person, you will likely be able to communicate with them using the radios. Under normal circumstances, expect about 1/2 mile to 1 mile in congested areas, more over open terrain. The claims of 5 to 10 miles may be valid if you are on one mountain peak, and the other people is on another mountain peak.
Popular Wireless has a great article on The Truth Behind the Marketing Claims for FRS and GMRS radios.
SC&E has a nice chart outlining the range differences between FRS, GMRS, and MURS.
GMRS Radio Reviews
Popular Wireless GMRS Equipment Review
Recommend a site
GMRS Repeaters
 Repeaters are GMRS radios that are capable of receiving and transmitting at the same time. They are usually located in a high location, such as the top of a building, commercial antenna, or top of a mountain. They allow GMRS radio users to communicate over a much wider distance. Ray Vaughan has a picture of his repeater in Miami.
For example, one GMRS user could be 25 miles from the repeater, and the other use 15 miles directly opposite the user on the other side of the repeater. The repeater extend the range of each user, allowing them to talk 40 miles apart! GMRS.org has a good description and diagrams of how repeaters work.
Popular Wireless has a good section devoted to setting up and maintaining a GMRS repeater station. See repeater-builder.com for a good section on Repeater Q&A as well as technical information.
The $100 Repeater by Jim Sharp
Barriers to Getting a GMRS station on the air at GMRSWeb.
Obtaining a GMRS License
Using GMRS radios on GMRS frequencies requires a license from the FCC. There are several good sites on the internet that discuss the process of obtaining the forms and filling them out:
Popular Wireless - Nice article on getting an GMRS station up and running
Filing for your GMRS license on the Web by Ben Gore
FCC GMRS Licensing Process by Choices in Personal Communications
Popular GMRS Radio Discussion Sites
Popular Wireless BBS - One of the more popular and active boards on the net
Personal Communications Discussion
Yahoo Groups
GMRS - Group dedicated to General Mobile Radio Service
GMRSWeb - Mailing list for GMRS Web magazine
Recommend a site
GMRS Sites on the Internet
Popular Wireless - Bar none, the best GMRS site on the internet
Personal Radio Steering Group (PRSG) - Informative write up on GMRS
G-M-R-S.com - focusing entirely on promoting the safe, professional and courteous use of FCC-authorized radio service.
GMRS.org - Introductory site to GMRS
See our Links page for GMRS-type services in other countries.
Recommend a site
GMRS Channels
 GMRS radios are usually used in duplex mode, that is they are capable of being programmed with two frequencies, a transmit and receive frequency. This allow the portable radio to contact repeaters and extend the range of their communications.
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Repeater Input
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Repeater Output
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467.550
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462.550
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467.575
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462.575
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467.600
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462.600
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467.625
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462.625
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467.650
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462.650
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467.675
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462.675
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467.700
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462.700
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427.725
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462.725
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CTCSS Codes
CTCSS (Carrier Tone Coded Squelch System) tones, also known “Privacy Codes”, are used to keep the speaker turned off until another radio with the same code is used. This way, multiple groups of people can be using the same channel, and they will only hear the communications destined for their group.
The codes listed below are “industry standard”, but each radio manufacturer may choose their own codes, leading the possibility of some codes not working with incompatible radios. Popular Wireless has a sample list of codes from six types of FRS radios.
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Code
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Tone
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1
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67.0 Hz
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2
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71.9 Hz
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3
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74.4 Hz
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4
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77.0 Hz
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5
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79.7 Hz
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6
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82.5 Hz
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7
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85.4 Hz
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8
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88.5 Hz
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9
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91.5 Hz
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10
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94.8 Hz
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11
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97.4 Hz
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12
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100.0 Hz
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13
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103.5 Hz
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14
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107.2 Hz
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15
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110.9 Hz
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16
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114.8 Hz
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17
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118.8 Hz
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18
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123.0 Hz
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19
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127.3 Hz
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Code
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Tone
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20
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131.8 Hz
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21
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136.5 Hz
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22
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141.3 Hz
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23
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146.2 Hz
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24
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151.4 Hz
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25
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156.7 Hz
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26
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162.2 Hz
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27
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167.9 Hz
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28
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173.8 Hz
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29
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179.9 Hz
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30
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186.2 Hz
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31
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192.8 Hz
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32
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210.7 Hz
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33
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210.7 Hz
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34
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218.1 Hz
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35
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225.7 Hz
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36
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233.6 Hz
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37
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241.8 Hz
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38
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250.3 Hz
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Federal Communications Commission (FCC) Information
FCC Website for GMRS Radios
FCC Callsign lookup (any service)
FCC GMRS callsign lookup
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