What is GMRS radio?

What is a GMRS radio?

A GMRS radio is a two-way radio for the General Mobile Radio Service, set out in 47 CFR Part 95 Subpart E. It works on 30 channels near 462 and 467 MHz and needs an FCC license. The FCC names short-distance voice with hand-helds, mobile radios and repeaters as the most common use.12

A license covers the licensee and family. The FCC says that if you receive a license, "any family member, regardless of age, can operate GMRS stations and units within the licensed system."1 Radios come as hand-helds, vehicle-mounted mobiles and base stations, plus repeaters.2 GMRS is one of the types of two-way radio.

What is FRS?

FRS, the Family Radio Service, is the license-free side of the same channels. It has 22 channels of 12.5 kHz each, all shared with GMRS.3 The FCC says FRS is licensed by rule, so no individual license is needed if you follow the rules.4

How do FRS and GMRS share 22 channels?

FRS channels 1–7 and 15–22 are also GMRS channels, and FRS 8–14 are GMRS hand-held channels. GMRS adds eight more channels at 467.550–467.725 MHz that FRS does not use. In all, the FCC counts 30 GMRS channels: 16 main and 14 interstitial.12 The table gives each shared channel with its power limit.

FRS limits are effective radiated power (ERP), while GMRS main-channel limits are transmitter output power, so 50 W is not a limit that applies to every shared channel. Fixed stations on the main channels are held to 15 W.69 Any channel can be looked up in the frequency charts.

What changed in the 2017 FCC rules?

In 2017 the FCC reorganized the Personal Radio Services in the Report and Order FCC 17-57, adopted May 18, 2017 and in force from September 28, 2017. It doubled the GMRS license term, raised FRS power to 2 W on most channels, allowed short data and ended dual-service FRS/GMRS hand-helds.1011

Before 2017 most "FRS" radios on the shelf were combination radios with 22 channels and 2 W on the GMRS channels, and most owners had no GMRS license. The FCC reclassified combination radios that meet its technical rules as FRS only.10 The FCC adds that existing radios were reclassified as either FRS or GMRS.4

Do I need a GMRS license?

Yes, for any GMRS station. The FCC says a license is required to operate a GMRS system. Anyone aged 18 or older who is not a representative of a foreign government may apply, and one license costs $35, lasts ten years and covers the licensee's immediate family.11213

The FCC says new licenses go only to individuals, not companies; a few older non-individual systems may still renew.1 Check your own case in the license checker. The 462.675 MHz "travel" channel is a habit; any GMRS channel may be used for emergencies.15

How do GMRS repeaters work?

A GMRS repeater receives on an input channel and retransmits on an output channel, which extends coverage. The eight inputs are 467.550 to 467.725 MHz and the eight outputs are 462.550 to 462.725 MHz, 25 kHz apart.2 These are the 8 repeater pairs.

FRS radios cannot use a repeater: they may transmit only on the 22 FRS channels, and the 467 MHz main channels are not among them.37

The rule text lists the inputs and outputs but not the pairs or the "R" numbers. The usual pairing keeps the same last digits and adds 5 MHz, so 462.675 MHz output goes with 467.675 MHz input. That is a common practice, not a rule.2 A licensee may open a repeater to anyone or limit it.13

The FCC also limits linking. GMRS stations cannot be connected to the telephone network or any other network to carry communications, except for remote control of a repeater. Linking repeaters over the internet to extend range violates sections 95.1733(a)(8) and 95.1749.1

How far does GMRS reach?

The FCC says a GMRS user can expect one to twenty-five miles depending on station class, terrain and repeater use.1 On FRS, the FCC says the usual range on channels 8–14 is less than half a mile, and longer on channels 1–7 and 15–22 depending on conditions.4

Cobra, which makes 2 W hand-held radios, lists these as typical:

These are the maker's typical figures for the 2 W class.16 A mobile radio with a roof antenna, up to 50 W, or a repeater on a hill does better. Model your own site in the range calculator.

What are handheld and mobile GMRS radios?

A handheld GMRS radio is a portable unit. It is the only station type allowed on the 467 MHz interstitial channels (FRS 8–14).29 A mobile GMRS radio is installed in a vehicle and may transmit at up to 50 W transmitter output on the 462 MHz main channels.9 Both can use a repeater.2

A hand-held that only does FRS must have a non-removable antenna.7 A GMRS hand-held is certified under the GMRS rules, and the 2017 rules ended combination hand-helds.11

Is GMRS the same in Canada?

No. In Canada, FRS and GMRS handhelds are license-exempt. Innovation, Science and Economic Development Canada (ISED) lists the same 22 simplex channels, 0.5 W ERP on channels 8–14 and 2 W on the others, in RSS-210.17 No GMRS license is needed.

The eight 467 MHz channels once held for GMRS repeater inputs "will no longer be made available for GMRS" in Canada, so US-style GMRS repeaters are not available license-exempt.18 ISED created GMRS-M, five 462 MHz frequencies for dog trackers and intercoms, in place of MURS.18

What is MURS?

MURS, the Multi-Use Radio Service, is a separate US service on five VHF channels at 151–154 MHz. It needs no individual license, is limited to 2 W transmitter power and, unlike FRS, may use an external antenna up to 60 feet above ground. Being VHF, it does not talk to FRS or GMRS radios.19

MURS stations may not be used as repeaters, and the antenna may be no higher than 60 feet above ground, or 20 feet above the building it is on.19 Channels 4 and 5 are often called "Blue Dot" and "Green Dot", a retail custom that is not in the FCC rules. Canada did not adopt MURS.18

How are FRS and GMRS different from PMR446?

PMR446 is the European license-free service at 446.0–446.2 MHz. It allows 500 mW ERP with a built-in antenna, no repeaters and 16 analog channels. FRS sits at 462 and 467 MHz, so the two cannot talk to each other, and neither radio is legal to use in the other's home market.2021 See PMR446.

FRS 2 W is four times the PMR446 limit of 0.5 W.620

How this relates to PoC radio

FRS and GMRS radios and PoC radios fill the same need, a group talking at the press of a button, with different limits. FRS and GMRS work directly between radios or through one repeater, in analog FM. PoC sends voice over the mobile network, so range is wherever there is signal.

The FCC's rule against linking GMRS repeaters over the internet marks the difference. A PoC service does that across a whole country; a GMRS repeater system may not.1 Hybrid radios put both in one case, with PoC where there is signal and direct radio where there is none. See PoC vs PMR446 for the European comparison and what is a two-way radio for the basics.

To choose between the two services, or against MURS and ham radio, see FRS vs GMRS.

Questions

Sources

1. General Mobile Radio Service (GMRS) · FCC
2. 47 CFR 95.1763: GMRS channels and authorized stations · eCFR, FCC
3. 47 CFR 95.563: FRS channels · eCFR, FCC
4. Family Radio Service (FRS) · FCC
5. 47 CFR 95.335: Equipment authorization required · eCFR, FCC
6. 47 CFR 95.567: FRS transmit power · eCFR, FCC
7. 47 CFR 95.587: FRS transmitter requirements · eCFR, FCC
8. 47 CFR 95.531: FRS communications · eCFR, FCC
9. 47 CFR 95.1767: GMRS transmit power limits · eCFR, FCC
10. Personal Radio Service Reform, FCC 17-57, 82 FR 41096 (29 August 2017) · Federal Register, FCC