GMRS repeaters and mobile radio setup basics

Rule text is quoted from 47 CFR Part 95 via eCFR (checked 2026-10-21). Radio figures come from FCC grants via fccid.io and from maker pages. We haven't tested any repeater or install. This is not legal advice.

How a GMRS repeater uses the channels

§95.1763 decides who may transmit where:

Channels	Who may transmit (quoted from §95.1763)	Role with a repeater
462 MHz main: 462.5500–462.7250 MHz (8 channels)	“mobile, hand-held portable, repeater, base and fixed stations”	Repeater output. You listen here.
467 MHz main: 467.5500–467.7250 MHz (8 channels)	“mobile, hand-held portable, control and fixed stations”, and mobiles and handhelds “only when communicating through a repeater station or making brief test transmissions”	Repeater input. Your radio transmits here.
462 MHz interstitial (7)	mobile, hand-held portable and base stations, not repeaters	Not used by repeaters.
467 MHz interstitial (7)	“Only hand-held portable units”	Not used by repeaters.

Each 467 MHz main frequency is exactly 5 MHz above a 462 MHz main frequency (467.550 ↔ 462.550, and so on). That’s why radios bundle the pair into one “repeater channel.” The maker pages for the MXT575, MXT500, MXT275 and GMRS-50X1 each list 8 repeater channels, one per 467 MHz main input. Repeater support for every radio we track is in the radio table.

Simplex vs repeater. Without a repeater, radios talk directly on the 462 MHz channels. A mobile or handheld may not transmit on the 467 MHz main channels except through a repeater or for “brief test transmissions” (§95.319(c)).

Tones: why a repeater may ignore you

§95.1777 allows “audible and subaudible tones used for receiver squelch activation and selective calling … or to access repeater stations.” Many repeaters only respond to a specific CTCSS or DCS tone. Midland calls repeater channels with separate transmit and receive tones “split-tone” channels (see the MXT275 and MXT575 pages). Get the input and output tone from the repeater owner or the directory listing.

Permission, licensing and ID

You need your own license. “A valid individual license is required to operate a GMRS station” (§95.1705). One license covers listed immediate family members. See how to get a license.
The repeater owner decides who uses it. Under §95.1705(d), an individual licensee “may allow any person to use … its GMRS repeater, or alternatively, may limit the use of its GMRS repeater to specific persons,” and may disallow specific persons. Owners may also share stations under the conditions in §95.1705(f): without charge, non-profit cost sharing, or reciprocal use, under a written agreement.
Finding repeaters. Community directories exist, such as the third-party site myGMRS. Listing details and access rules come from the owners, not the FCC. We aren’t affiliated with any directory.
Identify yourself. §95.1751 requires your call sign “following a single transmission or a series of transmissions” and at least every 15 minutes during longer exchanges, by voice in English or Morse tone. A repeater needn’t ID itself if it only retransmits stations under its own license and those stations identify properly.

No internet or phone linking for voice

§95.1749: “Operation of a GMRS station with a telephone connection is prohibited.” Repeater, base and fixed stations “may be connected to the public switched network or other networks for the sole purpose of operation by remote control.”
§95.1733(a)(8) also prohibits “messages which are both conveyed by a wireline control link and transmitted by a GMRS station.”

In plain terms, a repeater may be remote-controlled over a network, but linking voice traffic between repeaters over the internet isn’t something these rules allow.

Power limits that apply to repeaters and mobiles

From §95.1767:

Main channels: transmitter output of “mobile, repeater and base stations must not exceed 50 Watts.” Fixed stations: 15 W.
462 MHz interstitials: 5 W ERP for mobile, handheld and base stations.

The 50 W mobiles we track are filed below that limit:

Radio	Filed power, 462 MHz main	Basis	Grant
Midland MXT575	48.87 W	conducted	MMAMXT575
Midland MXT500	47.863 W	conducted (at antenna terminal)	MMAMXT500
BTECH GMRS-50X1	42.56 W (high)	ERP	2AGND50X1G
Midland MXT275	15.0 W (high)	conducted	MMAMXT275

Conducted and ERP figures aren’t directly comparable. See methodology.

Mobile install basics from the documents

Power supply. Midland’s user guides give 13.8 VDC nominal for the MXT575 and the MXT275 (vehicle 12 V systems). Follow the maker’s wiring and fusing instructions in the manual for your radio.
Antenna placement and RF exposure. The FCC grants set a minimum distance between the antenna and all persons. For gain limits on the same grants, see the antenna guide.

Radio	Minimum separation from all persons (grant)
Midland MXT575	40 cm
Midland MXT275	86 cm
BTECH GMRS-50X1	104.7 cm
Midland MXT500	151.8 cm

Duty cycle. The MXT575, MXT275 and GMRS-50X1 grants state a “maximum duty factor of 50 %.” The MXT500 grant comments we read don’t mention a duty factor. §95.1733(a)(10) separately bans “continuous or uninterrupted transmissions” except for immediate safety of life or property.
Antenna height. Structures over 200 ft (60.96 m) above ground, or over 20 ft (6.10 m) near airports, may face FAA/FCC requirements (§95.317).
Test briefly. “Brief test transmissions” are allowed if they don’t interfere (§95.319(c)). If you learn your equipment is malfunctioning, stop transmitting (except for emergencies) until it’s fixed (§95.319).

Quick checklist for a first repeater contact

Have your own GMRS call sign.
Get the repeater’s output frequency, input tone and output tone from the owner or listing, and ask for permission if it’s private.
Set the radio’s repeater channel to that pair (467 MHz in, 462 MHz out) with the tones.
Keep transmissions brief and identify with your call sign at the end and every 15 minutes.