FRS/GMRS

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GMRS: The General Mobile Radio Service (GMRS) is a land-mobile FM UHF radio service designed for short-distance two-way communication. Licensed. GMRS is standard band FM (FM).

FRS: The Family Radio Service (FRS) is a mobile radio system authorized in the United States since 1996. This personal radio service uses channelized frequencies around 462 and 467 MHz in the ultra high frequency (UHF) band. Unlicensed. FRS is narrow band FM (NFM).

FRS/GMRS Channels

Channel numbers commonly used on 22 channel FRS/GMRS dual service radios. Most radios of this type are not capable of repeater operation and do not include the repeater input frequencies.

FRS devices have a maximum power of ½ watt (500 milliwatt) effective radiated power and integral (non-detachable) antennas. If you operate a device under the rules that apply to GMRS, you must have a GMRS license. GMRS devices generally transmit at higher power levels (1 to 5 watts is typical) and may have detachable antennas. If you operate a radio that has been approved for both FRS and GMRS, and if you limit your operations to the FRS channels with a maximum power of ½ watt effective radiated power, you are not required to have a license.

Channel No. Frequency FRS FRS Max Output GMRS GMRS Max Ouput Usage/Notes
01 462.5625 FRS 1 500 mW GMRS 9 5 W Unofficial national calling channel
02 462.5875 FRS 2 500 mW GMRS 10 5 W
03 462.6125 FRS 3 500 mW GMRS 11 5 W
04 462.6375 FRS 4 500 mW GMRS 12 5 W
05 462.6625 FRS 5 500 mW GMRS 13 5 W
06 462.6875 FRS 6 500 mW GMRS 14 5 W
07 462.7125 FRS 7 500 mW GMRS 15 5 W
08 467.5625 FRS 8 500 mW
09 467.5875 FRS 9 500 mW
10 467.6125 FRS 10 500 mW
11 467.6375 FRS 11 500 mW
12 467.6625 FRS 12 500 mW
13 467.6875 FRS 13 500 mW
14 467.7125 FRS 14 500 mW
15 462.5500 GMRS 1 50 W
16 462.5750 GMRS 2 50 W
17 462.6000 GMRS 3 50 W
18 462.6250 GMRS 4 50 W
19 462.6500 GMRS 5 50 W Use restricted near Canadian border
20 462.6750 GMRS 6 50 W Unofficial emergency/traveler assistance channel (PL 141.3)
21 462.7000 GMRS 7 50 W Use restricted near Canadian border
22 462.7250 GMRS 8 50 W
467.5500 GMRS 1 in 50 W Repeater input
467.5750 GMRS 2 in 50 W Repeater input
467.6000 GMRS 3 in 50 W Repeater input
467.6250 GMRS 4 in 50 W Repeater input
467.6500 GMRS 5 in 50 W Repeater input. Use restricted near Canadian border
467.6750 GMRS 6 in 50 W Repeater input, Unofficial emergency/traveler assistance channel (PL 141.3)
467.7000 GMRS 7 in 50 W Repeater input. Use restricted near Canadian border
467.7250 GMRS 8 in 50 W Repeater input

Common PL / CTCSS Tones and Associated Tone Number Code 

TONE/Hz          TONE/Hz          TONE/Hz
 01: 67.0         07: 85.4         13: 103.5
 02: 71.9         08: 88.5         14: 107.2
 03: 74.4         09: 91.5         15: 110.9
 04: 77.0         10: 94.8         16: 114.8
 05: 79.7         11: 97.4         17: 118.8
 06: 82.5         12: 100          18: 123.0


Midland Extra Channels

Midland has started marketing "Extra Channels" on several of their radios. These extra channels are simply existing FRS/GMRS frequencies with hard coded tones and low power on the FRS-only channels.

Channel No. Actual Channel Frequency PL/DPL No. PL Tone/DPL Code
23 GMRS 1 462.5625 38 250.3
24 GMRS 3 462.6125 35 225.7
25 GMRS 5 462.6625 32 203.5
26 GMRS 7 462.7125 29 179.9
27 GMRS 15 462.5500 26 162.2
28 GMRS 17 462.6000 23 146.2
29 GMRS 19 462.6500 20 127.3
30 GMRS 21 462.7000 17 118.8
31 GMRS 2 462.5875 1 023
32 GMRS 4 462.6375 4 031
33 GMRS 6 462.6875 7 047
34 FRS 8 467.5625 10 065
35 FRS 10 467.6125 13 073
36 FRS 12 467.6625 16 115
37 FRS 14 467.7125 19 131
38 GMRS 16 462.5750 22 143
39 GMRS 18 462.6250 25 156
40 GMRS 20 462.6750 28 172
41 GMRS 22 462.7250 31 223
42 GMRS 1 462.5625 14 107.2
43 GMRS 3 462.6125 11 97.4
44 GMRS 5 462.6625 8 88.5
45 GMRS 7 462.7125 5 79.7
46 GMRS 15 462.5500 2 71.9
47 GMRS 17 462.6000 37 241.8
48 GMRS 19 462.6500 34 218.1
49 GMRS 21 462.7000 31 192.8
50 GMRS 2 462.5875 2 025


GMRS

General Mobile Radio Service (GMRS) - FCC Title 47 Part 95; GMRS radios operate on 8 UHF frequencies that were set aside by the FCC for family use. A license is required (five year term) which covers your entire family, including (grandparents, parents, brothers, sisters, cousins, aunts, uncles, in-laws, sons, daughters, and pretty much any one related by blood or marriage). The purpose is to facilitate the communications of families over a limited distance.

  • FCC License: Yes
  • Max Output: 50 watts on select channels
  • Frequency: 1 meter (UHF)
  • Bandwidth: standard FM (FM) ±5 kHz deviation
  • FCC Reg: Part 95

Applying for a GMRS license should be done online.

License Fee:
Since the FCC has eliminated the $5 per year regulatory fee, the cost for a family GMRS license has dropped from $90 down to $65. The fee, which was previously assessed at $5 per year, added $25 to the total cost of a GMRS license, which has a term of five years.

§ 95.119 Station identification.

(a) Except as provided in paragraph (e), every GMRS station must transmit a station identification:
(1) Following the transmission of communications or a series of communications; and
(2) Every 15 minutes during a long transmission.
(b) The station identification is the call sign assigned to the GMRS station or system.
(c) A unit number may be included after the call sign in the identification.
(d) The station identification must be transmitted in:
(1) Voice in the English language; or
(2) International Morse code telegraphy.
(e) A station need not identify its transmissions if it automatically retransmits communications from another station which are properly identified.

Ham radio license does NOT cover the GMRS frequencies.

View a table of FRS/GMRS Frequences and Channels.

GMRS Repeater

GMRS range is line of sight. A GMRS repeater with an antenna that is high above the surrounding terrain can extend the usable range over a wide area up to 20 miles or more. The GMRS-only channels are defined in pairs, with one frequency in the 462 MHz range for simplex and repeater outputs, and another frequency 5 MHz higher for repeater inputs.

To build a repeater use a quality bandpass with reject type UHF duplexor. With a license a GMRS user can transmit up to 50-watts of power. Build the repeater to transmit at full power, 50-watts.

Individual must apply to the FCC for a GMRS repeater control operator license.

FCC Considering GMRS Rule Changes

The FCC is seeking comment on a Notice of Proposed Rule Making in regards to GMRS, whether to do away with the license requirement or possible close down GMRS altogether. Considerations in the NPRM:

  • Eliminate GMRS licensing (aka “license by rule”), similar to the FRS and CB spectrum, or extend licensing term from five to ten years.
  • Relax eligibility requirements. Under the current GMRS licensing regulations, only those aged 18 years or older are eligible to apply for a GMRS license. According to the FCC, if licensing is eliminated, it will be very similar to the FRS service, which has no such age restriction, so they don’t find a reason to continue the age eligibility requirement.
  • Move to narrowband 12.5 kHz spacing. Currently GMRS uses 25 kHz spacing.
  • Decrease GMRS handheld radio output power from 5 to 2 watts.
  • Eliminate the use of repeaters in the GMRS service.

What does the future of GMRS hold? It is difficult to say. If the FCC takes GMRS away completely, then it will become illegal to use any of the FRS/GMRS combo radios. Repeater owners will have to turn off their repeaters.

Updated: Summer 2015 - Changes to individual license requirement have been approved. In 2015, the FCC ruled to keep the license requirement, but to remove the regulator fee for licensing. Adopted May 20, 2015. Will be in effect after a 90-day notification period to Congress. Fee will not be eliminated before August 18, 2015.

GMRS Discussion Online

Try to avoid "survivalist" forums discussing these radios. The SHTF / Survivalist forums tend to discuss illegal use of GMRS radio equipment. Furthermore, much of what is discussed on the survivalist forums is inaccurate including mods that typically will damage your radio equipment. Look for discussion groups that are technically oriented or forums shared by GMRS and HAM radio users. Although a HAM radio license does not grant access to GMRS frequencies, some HAM operators also have a family GMRS license and the majority of HAM radio operators are far more knowledgeable than any of the crazy folks over on the survivalist forums.

GMRS Transceivers (examples)

There are many GMRS HT (hand held transceivers) available. This list will focus more on units with repeater capability, in vehicle mobile units, and base units.

  • Midland MXT500-50 Watt GMRS MicroMobile® Two-Way Radio
  • Midland MXT275 MicroMobile® GMRS Radio – 15 watts Two-Way Radio
  • Midland MXT115VP3-15 Watt GMRS MicroMobile® Two-Way Radio
  • BTECH GMRS-20V2 20W GMRS Two-Way Radio
  • Wouxun KG-1000G GMRS Base/Mobile Two Way Radio

FRS

Family Radio Service (FRS) - FRS radios use narrow-band frequency modulation (NBFM) with a maximum deviation of 2.5 kilohertz. The channels are spaced at 12.5 kilohertz intervals.

  • FCC License: No
  • Max Output: 0.5 watts
  • Frequency: 1 meter (UHF)
  • Bandwidth: Narrow FM (NFM) 2.5 kHz deviation
  • FCC Reg: Part 95

FRS radios are limited to 500 milliwatts.

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 500 milliwatts.

FRS radios must use only permanently attached antennas, such as walkie-talkies; there are also table-top FRS "base station" radios that have whip antennas. This limitation intentionally restricts the range of communications, allowing greatest use of the available channels. The use of duplex radio repeaters and interconnects to the telephone network are prohibited under FRS rules.

Despite manufacturer advertising claims range is typically less much less than a mile.

View a table of FRS/GMRS Frequences and Channels.

Bubble Pack HT Combo Radios

FRS/GMRS consumer radios have been introduced with 22 channels, instead of the 14 channels associated with FRS. On this type of radio, transmitting on shared FRS/GMRS channels 1–7 requires a license if using more than 0.5 watt. Channels 8–14 are strictly license-free FRS channels. Transmitting on GMRS-only channels 15–22 requires a license.

These hybrid radios are often referred to as "bubble pack" radios, since they are often packed in a plastic shell, for hanging on a display shelf. Most bubble pack GMRS radios are simplex-only, so they do not function through a repeater. They operate only on the repeater output frequency (GMRS Channels 15 through 22).

FRS rules permit only 2.5 kHz (NFM) deviation on the FRS shared channels. GMRS uses ±5 kHz (FM) deviation on the GMRS channels.

FRS, GMRS, and Combination Intercom / Base Station

One very useful application for the band is as a wireless Intercom system. This works great from floor to floor within a building or house to shop Intercom. A big advantage is that the system is completely compatible with mobile HT units. Using PL tone you can block other FRS and GMRS users in the area.

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. Radios much be type 95A approved to be legally used on GMRS.

Few companies have embraced this very useful application for the band. A few companies produced Intercoms then discontinued the products. Here is a list of the ones out of production or possible still in production. Sometimes they can be found on eBay and Amazon.com

Some of these are FRS only, some are both. Part 95A Approved.

Flat table top intercom style units with attached antenna

  • Audiovox Multi Radio Station FRS1000 2-Mile 14-Channel FRS Two-Way Radio
  • Audiovox FRS GMRS Weather GMRS 2000 Multi Radio Station Base Station
  • Audiovox GMRS 3000 5-Mile 22-Channel FRS/GMRS Two-Way Radio with Mini Base Station
  • Memorex 14 channel FRS Base Station Model MK1800
  • Maxon TruTalk TK514 Base Station
  • Unwired Technology UFRBS10 2-Mile 14-Channel FRS Two-Way Radio Base Station
  • RadioShack 22 Channel GMRS FRS Base Station 21-1846

Upright base station style units with attached antenna

Car / Mobile

  • Midland MXT100 GMRS MicroMobile 2-Way Radio (5-watt)

The following units have not been verified as Part 95A approved...

What makes manufacturers cautious in producing GMRS products is the FCC being fickle on the regulations. The FCC needs to give manufactures confidence that they will not take the frequency allocation away or relinquish it to unlicensed freebanders.

Using a Business / LMRS Radio for GMRS

Most 70cm ham radios as well as UHF LMRS radios can be programmed and used on GMRS frequencies. Business radios are covered under Part 90 certification. The rules that apply to GMRS are in Part 95, which requires an additional certification process that most business radio manufacturers do not bother with. Part 95 covers all personal radio services and sub A is specifically GMRS.

The FCC states, "95.129 Station equipment; Every station in a GMRS system must use transmitters the FCC has certificated for use in the GMRS. Write to any FCC Field Office to find out if a particular transmitter has been certificated for the GMRS. All station equipment in a GMRS system must comply with the technical rules in part 95."

Language is ambiguous, and some will argue that it is permissible to use Part 90 certified radios on GMRS, however, many sources specifically indicate it is not legal unless the manufacturer has specifically had the radio Part 95 certified. Furthermore, any use of scrambling on GMRS is forbidden.

With that being said, it is actually somewhat interesting to note that there are a number of business band radios that have been part 95A certified. A search on the FCC web site can reveal this. This is good because business radios tend to be much better built and more reliable than anything made specifically for GMRS.

Ham Radio Transceiver on GMRS

It is forbidden to use an amateur radio transceiver on GMRS frequencies. Although it is possible to modify many manufacturer amateur radios to operate on GMRS, the amateur operator may lose license privileges by doing so. It is not illegal to perform the modification. It is illegal to use the modified transceiver on these frequencies. It is recommended that you do not perform such modification as to prevent accidental out of band operation.

Emergency use: There is a provision in FCC regulation whereas in the event of an emergency such as a life threatening event the use of an amateur radio transceiver out of band is permitted when no other means of communication are available. In this example, the amateur radio being used to find help on a GMRS frequency when no other frequency yielded a response and no phone service is available, said use is permitted. There is a list of some Ham Radios Easy to Mod for GMRS.

It would be very unusual that using an amateur radio on GMRS is the only way to receive help in an emergency.

Search FCC for Part 95A Certification

From the FCC web site do the following to perform a search:

  1. Browse to https://apps.fcc.gov/oetcf/eas/reports/GenericSearch.cfm
  2. Under Application Information: Application Status: select Grant Issued
  3. Under Equipment Information: Rule Parts (up to three): select 95A

GMRS Mobile and Base antennas

Base antenna:

  • Comet CA-F72GF UHF Base Vertical Antenna. N connector. 440-512 MHz, Tunable.

Use of DMR and other digital formats on GMRS

Use of DMR or other digital formats including dPMR, P25, NXDN is strictly forbidden by the FCC on FRS, GMRS, and MURS frequencies. There are increasing reports of violations in major cities in the United Stations. Most cases involve the use of MotoTRBO on GMRS repeater frequencies, which is in clear violation of FCC rules.

The intermod from digital repeaters creates an unpleasant sound on GMRS receivers and scanners monitoring those frequencies. The illegal use constitutes a problem for radio enthusiasts monitoring analog GMRS and those wanting to legally use GMRS repeaters. All violations should be monitored and reported to the FCC.

Related

See also:

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