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Product Support


What is a GMRS Radio?

General Mobile Radio Service (GMRS) is a licensed radio service for short and medium ranged communication. 


How is GMRS different from FRS or “normal" walkie talkies?

Family Radio Service (FRS) is an unlicensed radio service.  FRS and GMRS radios share the same 22 channels for communication, but GMRS radios are distinct in that: 


  • FRS radios are limited to a maximum transmit power of 2W.  GMRS radios can transmit at over 2W of power. Our TrailBlazer radios transmit at 2.5W.
  • GMRS radios can have removable antennas, FRS radios are required by the FCC not to have removable antennas.
  • GMRS radios can use repeaters to extend their effective range, FRS radios cannot use repeaters.
  • GMRS radios can use wideband FM audio.
  • GMRS radios can send data packets (store & forward).


Because of the higher power capabilities and ability to connect with repeater systems for much longer ranges operating a GMRS radio requires a license from the Federal Communications Commission (FCC). 


Can I use TrailBlazer GMRS radios in Canada? 

No.  The Canadian regulations limit low power license free radios up to 2W.  There is no equivalent to the US GMRS radios in Canada. 


How do I get a GMRS license? How much does it cost? 

A GMRS license does not require a test.  A license is obtained from the FCC (Federal Communications Commission) and costs $35 for a 10-year period.  The licensor must be at least 18 years old, but the license itself covers all of their immediate family including spouse, children, grandchildren, stepchildren, parents, grandparents, stepparents, brothers, sisters, aunts, uncles, nieces, nephews and in-laws. More information on FCC Licensing can be found here.


What is the purpose of a removable antenna on a GMRS radio? Why don't FRS radios have a removeable antenna?

  • For handheld radios, add-on antennas can provide greater range.
  • Removable antennas provide the ability to for mobile GMRS radios to be installed into a vehicle or used as a base station.
  • Per FCC Regulations, FRS radios must have a fixed antenna and cannot have a removable antenna.


What does a repeater do?

  • A repeater will take an incoming transmission and retransmit to a larger range, based both on the height of their placement and their power ability.
  • Repeaters are allowed to transmit up to 50W 
  • Repeaters are placed on top of buildings or on dedicated towers up to hundreds of feet in the air 
  • Because of the repeater antenna location and higher available power repeaters can provide coverage from ~5 miles to 15 miles to 25+ miles 


How does a GMRS repeater work?

  • GMRS radios using a repeater will transmit on a ‘repeater channel’ frequency (e.g. 17RP).  The repeater receives the signal and retransmits it on the associated GMRS channel (17). 
  • This is called a ‘duplex’ channel where a radio transmission frequency is different than its receiving frequency 
  • When the TX and RX frequencies are the same it is a ‘simplex’ channel


Can I use a normal radio as a repeater?

No.  Because repeaters receive signals and retransmit them ‘immediately’ they are specialized devices with filtering to prevent interference and noise between the incoming signals and the outgoing transmissions. 


How do I find a GMRS repeater in my area?

To use a repeater, you will need to know the GMRS channel that is uses and the CTCSS or DSC tone that will allow you to connect and activate the repeater.  In addition, repeaters owners will require permission to access the repeater. 

Repeaters may be run by a local GMRS radio club or by individuals.


  • myGMRS.com has a directory of repeaters and the ability to contact the owner for access. Please note that we are not affiliated with myGMRS.com nor any of its advertisers.


What is the difference between Wideband audio on GMRS and Narrowband audio? 

GMRS radios are capable of sending wideband FM transmissions. The transmissions take up more bandwidth in the transmission.  This can improve the sound quality and provide a fuller sound. 


Repeaters almost always operate on wideband 


What are the 22 channels for FRS and GMRS?

Please see our table here: FRS and GMRS frequencies


What is CTCSS and DCS?

Please see our article explaining CTCSS and DCS in depth here: What is CTCSS and DCS?


Can I use my TrailBlazer radio out of the box?

Yes.  The TrailBlazer radios work out of the box and are compatible with all FRS/GMRS radios and GMRS repeaters.


Can I program my radio with a computer?

Yes, if you have the Cobra Programming Cable, you can download the Cobra Programming Software for free and program the radios with a Mac or Windows computer.  With the Cobra programming software, you can set radio channels and settings and store the information into a radio profile.  Profiles can be loaded onto a single radio or multiple radios. 


The programming software also provides additional capabilities beyond what can be programmed directly on the radios themselves.  Advanced settings like wideband/narrowband, user level controls that prevent the radio from specific functions or changing specific settings and enabling/disabling channels can be set up with the CPS.  This can be helpful for radios you intend to be used by limited users, such as children and seniors.


Please refer to the Cobra Programming Software page for additional information.


What is a channel bank?

TrailBlazer radios group sets of channels into banks to provide easy operation and compatibility with Cobra FRS radios and other FRS/GMRS radios.  The banks are preprogrammed as: 


  • Bank 1
    • Channels 1-22 (+8 repeater channels if repeaters are turned on) 
  • Bank 2
    • 60 channels.
    • Compatible with Cobra RX series FRS radios and Midland 50 channel and 36 channel FRS and GMRS radios 
    • Channels 1-22  
    • Channels 23-60 with preset privacy codes 
  • Bank 3
    • Channels 1-22 with preset privacy tones.  Compatible with Cobra PX series FRS radios 
  • Bank 4 (select models)
    • Blank by default.  Bank 4 is used for the Frequency Find function.  When channels are found with the Find function they will be stored into Bank 4. 


How do I charge my TrailBlazer radios?

TrailBlazer radios use a standard USB-C port for charging the radio. 


What is the IP rating/ruggedness of the TrailBlazer radios?

The TrailBlazer 250 is rated IPX2 

The TrailBlazer 450 and 500 are rated IP54