GMRS

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General Mobile Radio Service. Evolution of the original "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 the higher power "bubble pack" radios for unlicensed FRS use.

Maximum power 50 watts on GMRS is except on shared narrowband channels (FRS channels 1-7) where maximum power is 5 watts. Wideband 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 repeaters with wider deviation receivers may be "opened" by strong or over-deviating FRS voice signals on adjacent simplex frequencies. For example, a GMRS repeater listening on 467.600 MHz may have its squelch opened by FRS signals on 467.5875 MHz or 467.6125 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

Simplex:

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.

Ch Freq MHz - Notes -
1 462.5625 Shared with FRS
2 462.5875 Shared with FRS
3 462.6125 Shared with FRS
4 462.6375 Shared with FRS
5 462.6625 Shared with FRS
6 462.6875 Shared with FRS
7 462.7125 Shared with FRS
15 462.5500 Shared with FRS
16 462.5750 Shared with FRS
17 462.6000 Shared with FRS
18 462.6250 Shared with FRS
19 462.6500 Shared with FRS
20 462.6750 Shared with FRS - GMRS Calling/Travel/Road Channel [recommended "travel tone" 141.3 Hz PL/CTCSS]
21 462.7000 Shared with FRS
22 462.7250 Shared with FRS



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