GMRS is a channelized radio service, operating in the UHF band, around the 70cm ham band. Though quite a capable and useful service, it has been badly tainted by being intertwined with the much less capable FRS service. Because of this, dedicated GMRS radios have been rare, and generally somewhat expensive. This may all change soon, due to some rule changes, with the charge being led by Midland.
        Already a very visible presence in the small hand held GMRS/FRS radio market, Midland has introduced a line of Pure GMRS mobile radios, with features and performance that better suit the long ignored GMRS market. These radios are small, well made, reasonably priced, and easy to use. They are also quite sophisticated compared to the little bubble pack FRS radios that presently rule this band.

        The Midland MTX90 is a GMRS only radio that puts out five watts, can be used with a repeater, and includes the tones that most repeaters require.
        Being  a  GMRS only radio means that this unit has a total of fifteen channels, rather than the 22 channels of the "hybrid" units. In the case of GMRS, less is more, because eliminating the FRS channels removes the restrictions placed upon FRS.
        This allows the unit to legally put out more power, have an external antenna, and access repeaters. It also means somewhat better build quality, and the requirement to get a license to operate.

        This unit is incredibly small. A look at the photos shows that it is hardly larger than the microphone it uses. In addition to the GMRS frequencies, seven weather band channels are included - receive only, of course.

        The radio is packed with an antenna, a standard microphone, a microphone holder, a power accessory cord (once known as a cigarette lighter adapter), a mounting bracket, and a tiny instruction manual. Basically, this is everything you need to get on the air, though you may want a better antenna.
        The small size, quick insert power plug, and magnet mount antenna encourage fast temporary installs. Really, installing this radio in a vehicle takes all of thirty seconds. Removal is just as easy. For those who are reminded of the old CB radios, there are some similarities, but GMRS has a distinct identity of its own. More permanent mounting solutions are easily available.

        The side of the unit is fitted with rail mounts, and mounting rails are included. A bracket is also included in the package. This is a special production run radio for Wal-Mart, and is the same model as the Midland branded MTX105. Similar models with more power, the MTX115 with fifteen watts, and the MTX400 with forty watts are also made. I picked this radio up for around $50 when a local store was clearing them out. Regular cost is just under $90.

                                                                                                GMRS
        GMRS is a channelized radio service, operating in the UHF band, around the 70cm ham band. Unlike FRS or CB, this is a licensed service. A GMRS license lasts for ten years, and costs $70. It can be used by the license holder and members of the immediate family. Unlike CB, the FCC actively enforces regulations and licensing requirements on GMRS. There is no test or knowledge requirement to become licensed. You pay your fee, and the FCC sends you your license and call sign.

        UHF is not capable of the long rage skip that is a feature of CB radio. It is very strictly limited to line of sight. Depending upon terrain, this could be as much as 20 - 30 miles; but don't count on it. Expected range for a pair of vehicle mounted radios is probably more like 3 - 5 miles. Terrain has a huge effect though, and in hills, or around large buildings, range can be cut by half or more.
        The antenna for this service is tiny, usually around six inches long. The radio itself is also very small. .

The Bad

        The band is not used in many countries.

        There is a limited assortment of quality gear available.
        A $70 fee is kind of expensive, particularly when CB is free, and HAM is only $15.

The Good

        It has most of the characteristics of 2 meter, but uses antennas less than half the size. It does not scatter to the extent of 440.

        If you get yourself a base or repeater, a mobile and a few handhelds, you can have a whole band to yourself in many areas.

So why bother?
        That's a question I can't answer. In my own case, I do it because I am a radio enthusiast, and because I have young nieces and a a nephew, that I may wish to talk to on camping trips, vacations, etc. There are large numbers of casual radio users out there, even in these cell phone saturated days.

                                                                                      Operation
         Basic operation is pretty simple. The GMRS service is not designed for hobbyists, experimenters, or radio experts. All controls are push button, including channel selectors. The only places where the manual may have to be consulted is for initial programming of tones for local repeaters, if required. The radio also features privacy codes, which can be handy. Basically, they filter out any signals not accompanied by the set privacy code. These really does not offer privacy, in the sens that it does nto prevent others from listening in, but it does filter out any other users fo a particular channel, and gives the illusion of having that channel to yourself.
         So how much range can you really expect from such a radio? Much depends upon who you are talking to, and what antenna you decide to use. Presuming the radio uses the included antenna mounted on a car roof, and is communicating with another radio similarly configured, probably 3 - 5 miles. Better antennas mounted at higher elevations give better performance. So what about those advertisements that promise a range of 25 - 40 miles? For this, you need a repeater.

Repeaters

        A repeater capable radio, operates in duplex mode, rather than simplex mode. What this means is that it transmits on one frequency,and receives on another. The repeater itself also operates in duplex mode, but differs from the regular radio operating in duplex, in that it transmits and rebroadcasts at the same time. Repeaters use the opposite frequencies of those used by the radios they serve. What this means is that the repeater will receive on the transmit frequency of the radios it serves, and transmit on the on the receive frequencies. So radios using a repeater will not be able to hear each other directly, since they transmit on a frequency different than the one on which they receive. Only through the re-transmissions of the repeater can they hear each other.
        Repeaters have been in common commercial and public service use for decades, and are also quite familiar to ham radio operators, but may be new to the casual operator. Repeater use is the secret to getting good range from these radios. As it comes out of the box, with the included antenna, this radio has a likely range of 3 - 5 miles. With a better mobile antenna, this can go up to 5 - 7 miles. Terrain will have an effect on range, as well as the nature of the radio with which you are communicating, but the numbers are close enough.
        To get really good range, you need to use a repeater. A repeater is a base station, transmitting at full power (50 watts, in the case of GMRS), with a very good antenna placed at a high elevation.  A repeater will get you that 25 - 35 mile range that the sales brochures are always bragging about. The reason they are able to do this is because they are stationary, and their permanent installation allows for exceptionally good antennas, mounted on towers or other high structures, and for transmitters that operate on the full 50 watts allowed by the service.
        Repeaters have been in use by government agencies for decades, and by ham radio operators for almost as long. While it is possible to find an 'open' repeater, which simply re-transmits anything transmitted on its received frequency, most are closed, and require simultaneous transmission of a sub-audable tone, in order to operate. The prospective repeater user must determine the tone frequency used for the repeater, and then set it on his radio. There is a decoder in the repeater that listens for this tone, and will only re-transmit when it hears the appropriate tone.
        Tones are used, not so much to restrict access, but to prevent a repeater from randomly re-transmitting static. Most repeaters list the required tones, either on their websites, or on repeater guides. Some ask for donations, but most are free to use. Many ham operators have become GMRS users due to the similarity fo repeater use, and so that they can share portions of the radio hobby with unlicensed users.

                                                                                           Antenna System
        One of the big advantages of GMRS over FRS, is the allowance of external antennas. A good antenna can make more of a difference in performance than doubling, tripling, or even quadrupling power. In FRS, an external antenna is strictly prohibited, and all type approved radios will have very small, no gain antennas, permanently attached. With a plethora of 70 cm ham radio gear out there, a really good antenna should be no problem.
        Unfortunately, one of the great disappointments of this radio is the included antenna. It is a bare bones magnetic unit which is adequate, but could be so much better. The radiator of this little antenna is about 6" long. This makes it a quarter wave at these frequencies, and uses the car body as a ground.

Full 5W Radio + External Magnetic Mount Antenna for extended range

15 High and Low Power (GMRS) Channels *FCC License Required

142 Privacy Codes to block other conversations

Channel Scan (to monitor radio activity) with Controlled Frequency Synthesizer

High-Grade Microphone

Silent Operation when beeps/tones are not desired