GMRS Radio: The Best Way to Communicate Off-Road in Your Jeep and 4x4?
A look at General Mobile Radio Service two-way radio from the off-road perspective.
What is GMRS? Why do those four letters keep popping up in campfire conversations when discussing off-road communication? What do those four letters mean? Why should you care? To answer those questions, let's explore the basics of GMRS.
What This Story Isn't About
This story is about GMRS (General Mobile Radio Service) and how it can benefit off-roaders. There are several other types of radio services available in the U.S., and all are regulated by the FCC (Federal Communications Commission), including some you've undoubtedly heard of and may have used on the trail, such as CB (Citizen's Band Radio Service), FRS (Family Radio Service), MURS (Multi-Use Radio Service), and Amateur Radio Service (aka ham radio). Each is unique and worthy of study, but GMRS is the topic of the day. Oh, and it's important to note that this story is reflective of the U.S. market.
GMRS Simply Defined
As noted on fcc.gov, GMRS has 30 total channels. Channels 1-7 are limited to a maximum effective radiated power (ERP) of 5 watts, channels 8-14 are limited to a maximum of ½-watt ERP (the FCC only allows handheld radios to transmit on these channels), channels 15-22 (and the eight repeater channels—more on those later) can have a maximum ERP of 50 watts. GMRS allows analog FM voice operation in the UHF (ultra high frequency) band, around 462 MHz and 467 MHz. Note: FCC rules allow GMRS radios to transmit digital data ("a brief text message," per the FCC's description) and share GPS location information from handheld portable radios, but the pool of radios capable of this are small at this time.
Notice we're using the term "channels" and not "frequencies." Of course, GMRS radios transmit and receive on specific frequencies, but GMRS radios are "channelized." This means that most GMRS radios display channel numbers by default, and not frequencies. The benefit to this is ease of use. You can simply say "let's use channel 16," for example, and anyone on an FCC-approved GMRS radio should be able to talk to you. This is by design, and is easier than saying "go to 462.575 megahertz," which is the frequency for GMRS channel 16.
It's important to note that GMRS requires an FCC license to transmit, but one is easy and inexpensive to acquire. You may apply for a GMRS license if you are "18 years or older and not a representative of a foreign government." A GMRS license requires no test, it's only $35, it's good for 10 years, and according to the FCC, "If you receive a license, any family member, regardless of age, can operate GMRS stations and units within the licensed system." A license can be obtained by going to the FCC Universal Licensing System (ULS) website to complete the application and pay the fee. Once approved, you'll be issued a call sign consisting of four letters and three digits. GMRS rules require that you ID using your callsign "following a single transmission or a series of transmissions and after 15 minutes and at least every 15 minutes thereafter during a series of transmissions lasting longer than 15 minutes."
The preceding is a portion of the FCC's GMRS requirements. A more detailed overview of GMRS rules and requirements can be found in the GMRS section of the National Archives and Records Administration website.




