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2020-08-04

GMRS and You




With the availability of handheld radios that are more powerful than cheap walkie-talkies, even more powerful radios for your home and vehicles, antenna masts and a small network of repeaters, GMRS allows your family some of the benefits of amateur radio, at a marginal cost, and without every member having to pass an exam. With a decent home and mobile GMRS radio set-up, your family could likely stay in touch even if you stray several miles from home for work or errands.

With the potential of a wide-spread infrastructure outage in an emergency, and increased tracking of location data via smart phones, payment card transactions and the like, adding GMRS to your family's communications strategy can make a lot of sense.

FRS vs GMRS

General Mobile Radio Service (GMRS) is a UHF Land Mobile Personal Radio Service, not much unlike Citizens Band (CB) or Family Radio Service (FRS). In fact, 14 frequencies used by GMRS are shared with FRS.

Up until the rules changed in 2017, one had to obtain a GMRS license to use channels 15-22 on FRS/GMRS handheld radios that look a lot like the one on the left in the title photo above. That radio is actually a 5 watt Midland GXT-1000 GMRS radio, but with a few caveats, it can be used for FRS as well.

Recent changes were made to allow up to 2 watts on channels 1-7 and 15-22 as part of FRS without obtaining a license. Channels 8-14 are still reserved solely for FRS use in the US, with a maximum of 500mW output. A number of FRS radios are available that run close to 2W on legal channels, but today I'll be focusing on GMRS specifically. The primary differences between FRS and GMRS are:
  • GMRS handheld radios are allowed to transmit up to 5W
  • GMRS mobile and base-station radios are allowed up to 50W
  • Removable antennae are allowed
  • Repeaters can be used on GMRS
  • An FCC license is required for GMRS, but there is no exam.
  • Businesses can legally use FRS for operations, but business use of GMRS is mostly disallowed.

The Rules

A short, multi-page primer on GMRS is provided by the FCC.
The full rules for operating on GMRS are in FCC Part 95 subpart E.

The short, short version of the rules that should cover most of the highlights:
  • No "public broadcast" messages, advertising or music
  • No profanity
  • Only communicate with other GMRS or FRS users. Communication with amateur radio stations is not allowed.
  • No "Jamming" or continuous transmissions
  • Don't use GMRS to assist in any criminal activity
  • You must identify your call sign (e.g. WRBX000) in English or morse code
    • At the end of a single transmission that you do not expect a reply to
    • At the end of a conversation
    • At least once every 15 minutes while communicating
  • You can authorize any family members to use your license with your permission.
    • Your parents, children, grandparents, nieces, siblings and uncles can legally operate on GMRS under one single license, if you give them permission and ensure they know the rules.
    • If they break the GMRS rules under your license, your license is likely in jeopardy. You are ultimately responsible for the actions of those using your license.
While GMRS is provided as a convenient way for family members to stay in touch, an authorized GMRS user is allowed to talk to others outside of their family. They do not need to be physically close enough to you to communicate with you as the license holder as long as they obey the rules.

Licensing

Most adult United States citizens are eligible to apply for a GMRS license. As of 2020, the license fee is $85, and it is valid for 10 years from the date of issue.

One can apply for a GMRS license online through the Universal Licensing System, or by mail. Either way, you must fill out FCC Form 605. Filing online requires you to register for an FCC Registration Numer (FRN) if you do not already have one. Amateur radio operators may use their existing FRN, for example.

Once logged in to ULS, click "Apply for a new license" and choose "ZA - General Mobile Radio Service" from the very bottom of the drop-down list.

Upon completion of FCC Form 605 for GMRS, you will be required to make an online payment. Your license will usually show up within a few hours or on the next business day. You will also likely receive an email about your license grant.

Hardware

YOU MUST NOT USE AMATEUR RADIO EQUIPMENT* ON GMRS.

Transceivers specifically designed for amateur radio are not allowed on GMRS. Some hams use commercial radios that have been tuned to work on amateur radio frequencies, and there's a bit of a grey area there.

Until recently, hardware specifically designed to take full advantage of GMRS was pretty rare. Radios must be type-certified under FCC Part 95 to operate on GMRS and strict standards must be met with regard to channel deviation, frequency stability at a wide variety of temperatures, and spurious emissions. It just so happens that commercial land mobile UHF Radios type-certified under FCC Part 90 meet or exceed the specifications for GMRS, so long as they do not exceed 50 watts of output power. As such, many GMRS users will re-program commercial UHF radios to operate on GMRS frequencies. The FCC hasn't ever given a straight answer about if this is allowed, but most repeater operators are okay with it. The Motorola Radius in the above photo is one of these, but a variety of 15-45 watt mobile radios and 2-5 watt handhelds from the commercial lines of Motorola, Kenwood, Bendix/King and others can often be found inexpensively on the used market. Just make sure you, or the seller, can program them properly.

BTech (purveyors of the ubiquitous, cheap "Baofeng" ham radios) markets two GMRS-specific radios: the GMRS-v1 handheld and the GMRS-50X1 mobile radio. These two have been type-certified for GMRS, have the ability to use GMRS repeaters, and are legal. The GMRS-V1 is, in fact, the only GMRS-specific handheld radio I was able to find that has repeater capability.

Midland, Cobra, and Uniden have also been making a variety of type-certified GMRS radios. Most of the handheld units, like the Midland GXT-1000 I have, do not have the capability to use GMRS repeaters, but the Midland Mobile and Micro-Mobile radios, designed to be installed inside vehicles, do have repeater capability.

Most GMRS radios are interoperable with FRS radios. The GMRS-specific radios mentioned above may have more than 22 channels, but channels 1-22 are almost guaranteed to work between any GMRS and FRS radio. If your family does a lot of outdoor activity, you may find that inexpensive FRS radios work fine for kids, and your GMRS radios will let you communicate with them.

Many old-school GMRS users refer to frequencies -- and especially repeaters, by the kilohertz part of the frequency only. I suspect this persists in part because GMRS users are begrudgingly sharing practically all of their frequencies with FRS users and dislike the concept of channel numbers. At any rate, "700" refers to either 462.700 MHz, or a repeater that uses 467.700 MHz on the input and 462.700 MHz on the output.

You can see actual frequencies in this chart on Wikipedia:

Repeaters

Like amateur radio, GMRS operators can run repeater systems. These repeater systems listen 5MHz higher than the base frequency, and re-transmit the signal on the base frequency so that all radios listening can hear the message. Not all regions have GMRS repeaters, but here in the Kansas City area, there are several to choose from. Unlike amateur radio repeaters, most of them require permission from the repeater operator before you use them.

MyGMRS.com is probably the closest thing there is to a directory of all GMRS repeaters in the United States. You can browse the repeater listings without signing up for an account, but many repeater details (such as the CTCSS or DCS codes to use them) are hidden until you log in. Some of these details are completely unlisted, instead requiring you to ask the repeater owner for permission. You can only create a MyGMRS account once your GMRS license has been active for a day or two and the website has imported your license from the FCC.

You can also buy or build your own GMRS repeater, and it probably comes as no surprise that commercial repeater hardware is also quite common. Repeater building is a complex topic I won't cover here, but the cost is usually pretty significant.



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