# A GMRS Guide

Here are some things to know about GMRS (General Mobile Radio Service) if you're thinking about getting a license, or you recently got one.

## Licenses, Callsigns, and Families

GMRS licenses don't require passing any exams but do require a small fee. The callsigns are too long (mine is 11 syllables). But your whole family can use the same license and callsign.

> Immediate family members are the licensee's spouse, children, grandchildren, stepchildren, parents, grandparents, stepparents, brothers, sisters, aunts, uncles, nieces, nephews, and in-laws.

Note that means it matters who holds the license. An adult with children and parents pulls the most people under one callsign.

## Radios

Several of the Chinese radio manufacturers that have been making waves in ham radio also make GMRS models. They range in price from about $30 to $160, and some of the cheaper ones are very capable, minus fancy things like GPS.

Cobra, Motorola, Midland, and Uniden still make blister-pack retail radios of course, but they're often less capable than the Chinese radios from Baofeng, BTECH, Radioddity, and Wouxun for the price.

## Simplex Channels

Simplex channels (same frequency for send and receive) are numbered, 1 through 22.

### 1 - 7

You can use any of the 22 channels, but you'll probably want to stick with 1 through 7 because these allow up to 5 Watts of transmission power. That's about what you can get with a handheld amateur radio.

### 8 - 14

Channels 8 through 14 only allow 0.5 Watts. The bandwidth of 8 through 14 is also smaller. If you're close enough to the radios you want to reach, these should have less traffic on them.

### 15 - 22

You can use these too, and they allow the same wider bandwidth as 1 through 7, and a lot more power (50 Watts), but they're also repeater outputs, so it's best to leave them for repeaters.

## Repeaters

As mentioned above, repeater output channels are shared with Simplex, channels 15 through 22.

There are two conventions for naming the channels. One is to add an R, so R15 through R22, or 15R through 22R. The other is to use the decimals of the output frequencies, so 15R is also known as 550 and 22R is also known as 725. All the outputs are in the 462 MHz range.

Because there are two conventions, I prefer to name my repeater channels 550R15 through 725R22 (or 15R 550).

Inputs are +5 MHz from the output channels and don't need their own names. They don't overlap with FRS and GMRS simplex channels.

Many GMRS repeaters are closed, meaning you shouldn't use them without permission, or without paying dues if required. myGMRS.com usually has at least contact info for any repeaters in your area.

## Tones and Codes

CTCSS tones and DCS codes are sometimes called privacy tones and codes, but they offer no privacy. What they do is let you filter out someone else's conversation, which can also be really annoying because it's harder to know if someone else is using the same channel.

141.3 Hz is known as the "travel tone" and there's a fair chance you can open a repeater with this tone on at least one of the repeater channels. If a repeater uses this tone, it's probably an open repeater, but it's polite to make sure before you start using it.

I configure all of my generic channels to transmit the travel tone. Simplex channels I leave with no receive tone (signals without a tone will open the squelch), and repeater channels I configure with the travel tone for both transmit and receive.

If your radio supports additional user-configurable channels, that's where you want to put the channels and tones or code you'll use with your family, as well as any repeaters in your area. For example, Seattle ACS has four repeaters with other tones than the travel tone.

## Emergencies

Channel 20 with the travel tone (141.3 Hz) is used as an emergency channel by convention (like CB channel 9). If your radio supports dual receive, you could set the secondary channel to 20R with the travel tone so that you'll hear any cries for help.

Seattle ACS, as an example again, has one repeater on Channel 20, with a 141.3 input tone. Assume this repeater should not be used for non-emergencies, unless there's a formal net.

## Nets

Nets allow you to make sure you know how to use your radio, and confirm that you can reach the repeater okay, and people can hear and understand you. Sometimes people talk, but often the nets are purely for practice and signal reports.

## Data and Text

GMRS and FRS radios are allowed to send a small amount of data, like GPS coordinates or text messages, but there aren't standards, so you need a pair of matching radios.

Garmin makes some fancy but expensive GPS + GMRS units.

BTECH has the [GMRS-PRO](https://baofengtech.com/product/gmrs-pro/) for a lot less than a Garmin, with GPS, data and text, and an app to control it all.

Note that GMRS radios that can send data have fixed antennas, while radios without can have removable ones that you could even attach to an antenna mounted on your roof.

## Identification

Station identification can be done using audible morse code, but only repeaters really do this. You should identify with your callsign every 10 minutes and at the end of your transmission.

All GMRS channels, including repeater outputs but not including repeater inputs, are shared with FRS, and FRS does not have an identification requirement. But technically if you're using a GMRS radio (at GMRS power) you should identify anyway, even if you're chatting with someone on an FRS radio.

## Enforcement

As long as you don't make a nuisance of yourself, you're unlikely to ever have to worry about enforcement. GMRS is not self-regulated like ham radio, but many GMRS users, especially repeater owners, can be persnickety about insisting that you use a GMRS licensed radio when talking to them, use proper identification, etc.

It's always polite to follow the rules, so please do, but the FCC does not ask you to help them enforce their rules, and there's no incentive to do so.

The rules aren't long or especially hard to read, so take a look at [Part 95 Subpart E](https://www.ecfr.gov/current/title-47/chapter-I/subchapter-D/part-95/subpart-E) for yourself to learn the details. Skip to [§ 95.1731](https://www.ecfr.gov/current/title-47/section-95.1731) for permissible uses.