GMRS

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General Mobile Radio Service

GMRS (and by extension, FRS) evolved out of the original 465 MHz "Class A" CB service. Calling frequency 462.675 MHz CTCSS 141.3 Hz (sometimes referred to as the "travel channel"). See page for FRS for information about combined FRS/GMRS "bubble pack" radios. As of late 2017, the FCC legalized the 8 "GMRS only" 462 MHz frequencies as part of the FRS service, changing the number of shared frequencies from 7 to 15 and legalizing the use of all 22 channels for simplex use under the FRS rules. GMRS license holders are still granted higher transmit power privileges and use of repeaters under the new rules.

Maximum power 50 watts on GMRS is except on shared narrow band channels (FRS channels 1-7) where maximum power is 5 watts. Wide band FM (25 kHz or 20K0F3E, 16K0F3E or similar) or narrow band FM (11K2F3E, 11K0F3E and several other emissions with even narrower bandwidths) allowed on the 16 GMRS only frequencies for repeater or simplex use. Low power mobile and portable radios generally use narrow FM for compatibility with other handheld FRS radios aimed at the consumer market.

GMRS Simplex Frequencies GMRS Simplex Channels

  • Channel 01 - 462.5625 MHz
  • Channel 02 - 462.5875 MHz
  • FRS Channel 03 - 462.6125 MHz
  • FRS Channel 04 - 462.6375 MHz
  • FRS Channel 05 - 462.6625 MHz
  • FRS Channel 06 - 462.6875 MHz
  • FRS Channel 07 - 462.7125 MHz
  • FRS Channel 08 - 467.5625 MHz
  • FRS Channel 09 - 467.5875 MHz
  • FRS Channel 10 - 467.6125 MHz
  • FRS Channel 11 - 467.6375 MHz
  • FRS Channel 12 - 467.6625 MHz
  • FRS Channel 13 - 467.6875 MHz
  • FRS Channel 14 - 467.7125 MHz
  • FRS Channel 15 - 462.5500 MHz
  • FRS Channel 16 - 462.5750 MHz
  • FRS Channel 17 - 462.6000 MHz
  • FRS Channel 18 - 462.6250 MHz
  • FRS Channel 19 - 462.6500 MHz
  • FRS Channel 20 - 462.6750 MHz
  • FRS Channel 21 - 462.7000 MHz
  • FRS Channel 22 - 462.7250 MHz

Channels 8-14 are FRS-only (unlicensed) - see the page for FRS for more information. GMRS users may transmit up to 5 watts on 462.5625 MHz, 462.5875 MHz, 462.6125 MHz, 462.6375 MHz, 462.6625 MHz, 462.6875 MHz and 462.7125 MHz. Licensed GMRS users and unlicensed FRS users are limited to 0.5 watts on 467.5625 MHz, 467.5875 MHz, 467.6125 MHz, 467.6375 MHz, 467.6625 MHz, 467.6875 MHz and 467.7125 MHz.


Repeaters

Ch Output MHz Input MHz
15 462.550 467.550
16 462.575 467.575
17 462.600 467.600
18 462.625 467.625
19 462.650 467.650
20 462.675 467.675
21 462.700 467.700
22 462.725 467.725


Many GMRS users refer to the wide band GMRS frequencies by the three digits after the frequency in MHz notation:

  • GMRS 550 - 462.5500 MHz
  • GMRS 575 - 462.5750 MHz
  • GMRS 600 - 462.6000 MHz
  • GMRS 625 - 462.6250 MHz
  • GMRS 650 - 462.6500 MHz
  • GMRS 675 - 462.6750 MHz
  • GMRS 700 - 462.7000 MHz
  • GMRS 725 - 462.7250 MHz


Resources and Further Reading:

List of Grandfathered GMRS Users Licenses - Grandfathered GMRS Entities by Zip Code

MyGMRS.com GMRS user resource

MyGMRS.com GMRS repeater listing - GMRS repeaters nationwide

ArtSci Publications - nationwide amateur and GMRS repeater listing



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