1. What is GMRS?
2. Whatis the GMRS Frequency range?
3. Do I need a professional license for operate GMRS radio?
4. How to apply for the GMRS license?
5. Does a ham radio license allow me to transmit on GMRS frequencies?
6. Can I use a ham radio on GMRS frequencies?
7. What antenna does GMRS use?
8. What is the maximum distance you can have between two GMRS radios?
9. What is a GMRS repeater?
10. How to find a GMRS repeater in my area？

1. What is GMRS?

GMRS, the General Mobile Radio Service, is one of the popular radio services in the United States. It’s designed for short-distance two-way voice communication and authorized under FCC part 95E (47 C.F.R, Part 95 Subpart E). Most people that use GMRS not always but mostly it is used in groups off-roading hiking, Marathon and others.

GMRS uses 22 channels in UHF, shares a frequency band with FRS near 462 and 467 MHz. Most GMRS radios, if it’s a repeater capable GMRS radio, has eight or more channels set aside for repeaters.

2. Whatis the GMRS frequency range?

*FREQUENCY TABLE & NOTES FROM WIKIPEDIA*

Table Notes:

(1) Shared FRS and GMRS simplex.
(2) Shared FRS and GMRS simplex; GMRS repeater output.
(3) GMRS repeater input. The output frequency of this repeater input is the input frequency minus 5 MHz.
(4) FRS transmissions are limited to bandwidth of 11 kHz with a transmitter deviation of +/- 2.5 kHz. Channels are on 12.5 kHz centers.
(5) GMRS transmissions may have a bandwidth of 16 kHz with a transmitter deviation of +/- 5.0 kHz. Channels are on 25 kHz centers.
(6) GMRS transmissions are limited to a bandwidth of 11 kHz with a transmitter deviation of +/- 2.5 kHz. Channels are on 12.5 kHz centers.
(7) National GMRS calling channel (CTCSS tone 141.3 Hz).

Note: Some inexpensive GMRS mobiles and portables do not fully comply with FCC permissible modulation bandwidth for GMRS and thus have weak transmitter audio and reduced range.

3. Do I need a professional license for operate GMRS radio?

YES. To transmit on GMRS channels in the U.S., you do need a license and call sign from FCC (but some GMRS compatible equipment is license-free in Canada). It’s not a ham license and there’s no test.

Basically you just need to pay $70 to FCC for the privilege of using these free airwaves for 10 years. The FCC has announced that they will be reducing the cost of that license to $35. So currently $70 for 10 years, soon it will be $35 for 10 years.

An individual can have a GMRS license, and it’s perfectly legal to conduct commercial activity on GMRS. You can actually use one license for your entire immediate family. But a company itself cannot have a GMRS license, at least not anymore.

4. How to apply for the GMRS license?

Go to FCC website—— fill out a form —— pay the license fee —— receive your call sign within 24 working hours.

Click the link below to learn the application step-by-step: 《How to Apply for GMRS License》.

In any case, whether using a GMRS repeater or not, every GMRS operator has to announce the call sign at the end of a transmission, or at least once every 15 minutes. You can just spell the call sign or send it with audible tones using Morse code.

5. Does a ham radio license allow me to transmit on GMRS frequencies?

A HAM license does not supersede a GMRS license, and a ham license does not authorize a person to transmit on GMRS frequencies.

According to FCC rules part 95.1705, a valid individual license is required to operate a GMRS station. So even if you're a licensed Ham already, and you want to transmit on GMRS frequencies, you still NEED to apply for a GMRS license on FCC's official website.

6. Can I use a ham radio on GMRS frequencies?

A ham radio, unless it's FCC Part 95E approved, cannot transmit on GMRS frequencies. But if it's Part 95E certified, it's called GMRS radio instead of Ham radio. So, for instance, you can't use UV-5R to transmit on GMRS frequencies (UV-5G would be a right choice).

7. What antenna does GMRS use?

You can directly purchase a standardized GMRS antenna. GMRS radio typically uses a BNC Male or UHF Male connector, it should be pre-tuned and pre-cut. So you don’t have to do anything else but install it.

In addition to this, GMRS is in the UHF band, it means you can use any UHF antenna. But you will have to trim and tune that antenna specifically to the GMRS frequencies.

8. What is the maximum distance you can have between two GMRS radios?

As with other UHF radio services, reliable range is considered to be line-of-sight and the distance to the radio horizon can be estimated based on antenna height. Theoretically, the range between two hand-held units would be about one or two miles (about 1.5–3 km); mobile units have higher antennas and a range of around 5 miles (8 km). A GMRS repeater with an antenna that is high above the surrounding terrain can extend the usable range over a wide area – for example, up to a 20–mile (32.2 km) radius around the repeater station.[8] Obstructions such as hills and buildings can reduce range. Higher power does not necessarily give a proportional increase in range, although it may improve the reliability of communication at the limits of line-of-sight distance.

9. What is a GMRS repeater?

Repeater is basically a radio that can receive and transmit at the same time. Usually, they have high power and huge antennas. What the repeater does is receive your signal and rebroadcast it over a wider area, and that basically extends your talking range.

Usually, the GMRS repeater is placed somewhere that can reach over a wide area, such as the top of a high mountain. For example, if you’re on one side of a mountain, and you’ve got somebody on another side, you can never talk to each other because of the natural obstacles. But if you get a repeater on top between you guys, you can talk to each other through that repeater.

Comparing with Ham repeater technically, GMRS repeater is just a repeater that is set up to use GMRS frequencies only. The configuration of GMRS repeaters is standardized, but in Ham radio, the configuration is more complicated, it can be what the operator wants it to be. Therefore,  GMRS repeaters are much easier to use.

You have to get permission from the repeater owner before you can use the repeater. Most of the repeaters in the United States are privately owned, usually by GMRS radio clubs, but also someone just build a repeater on his roof for personal use.

The GMRS repeater is a limited resource, because it allows only one conversation at a time. So please don't waste the resource if you're close enough to talk with each other.

10. How to find a GMRS repeater in my area？

To use a repeater,  you need to know the frequency or the GMRS channel that it uses and the CTCSS tone that will allow you to connect and activate the repeater. So at first, you need permission to use a repeater, get the above information and program that into your GMRS radio.

①Contact your local GMRS clubs if you know them.

②Search on myGMRS.com. You can view all the repeaters that are already registered in this community. There you can know who to contact if you need permission.