General Mobile Radio Service

The General Mobile Radio Service (GMRS) is a land-mobile FM UHF radio service designed for short-distance two-way communication. It requires a license in United States but some GMRS compatible equipment can be used license-free in Canada. The United States permits use by an adult individual who possesses a valid GMRS license, as well as his or her immediate family members. Immediate relatives of the GMRS system licensee are entitled to communicate among themselves for personal or business purposes, but employees of the licensee, who are not family members, are not covered by the same licence.

GMRS radios are typically handheld portable devices much like Family Radio Service (FRS) radios, and share the FRS frequency band near 462 and 467 MHz. Mobile and base station-style radios are available as well, but these are normally commercial UHF radios as often used in the public service and commercial land mobile bands. These are legal for use in this service as long as they are GMRS type-approved. They are more expensive than the walkie-talkies typically found in discount electronics stores, and are generally considered higher quality.

Any individual in the United States who is at least 18 years of age and not a representative of a foreign government may apply for a GMRS license by completing the application form, either on paper or online through the FCC's Universal Licensing System. No exam is required. A GMRS license is usually issued for a 5-year term. For most applications the fee is $70.

A GMRS individual license extends to immediate family members and authorizes them to use the licensed system. GMRS license holders are allowed to communicate with FRS users on those frequencies that are shared between the two services. GMRS individual licenses do not extend to employees.

New GMRS licenses are only being issued to individuals. Prior to July 31, 1987, the FCC issued GMRS licenses to non-individuals (corporations, partnerships, government entities, etc.). These licensees are grandfathered and may renew but not make major modifications to their existing licenses.

As with other UHF radio services, reliable range is considered to be line-of-sight and the distance to the radio horizon can be estimated based on antenna height. Theoretically, the range between two hand-held units would be about one or two miles (about 1.5–3 km); mobile units have higher antennas and a range of around 5 miles (8 km). A GMRS repeater with an antenna that is high above the surrounding terrain can extend the usable range over a wide area – for example, up to a 20-mile radius around the repeater station. Obstructions such as hills and buildings can reduce range.

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