GMRS radios operate in the same frequency bands as FRS but at higher wattage so a license is required.

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1 I was asked about putting together an article about ham & CB radios after someone at the March meeting (I don't remember who it was) mentioned about the club using ham radios because of their range and clarity. It was also mentioned they were using 2 meter radios in off road racing and that you did not need an FCC license to use it. Here is some of the information that I found out after making some phone calls to the Green Valley Amateur Radio Club and ARRL (formerly The American Radio Relay League, it is the national association for Amateur Radio) and checking information on sanctioned off road races. Depending on the race series, or sanctioning body, race radios need to operate in 150 to 158 MHz range. In those frequencies ( MHz) are "VHF business band", the unlicensed Multi Use Radio Service (MURS), and other 2-way land mobile FM. The MHz is VHF marine radio narrow band FM with MHz (channel 16) being the maritime emergency and contact frequency. Of those frequencies, only the MURS frequencies VHF 151 & 154 MHz are authorized for use without an FCC license. A 2 meter radio can be set to use those frequencies. But under the FCC MURS regulations the radios have to have up to 5 preset frequencies and can not put out more than 2 watts, so that makes using a 2 meter radio illegal because usually minimum wattage output is 5 watts on low power. The average 2 meter radio puts out 25 to 50 watts and some even more than that. The 2 meter radio I have in my Jeep puts out up to 50 watts. Compare that to a legal CB radio of 4 watts. So that brings us to the MHz marine band which also does not need an FCC license as long as you are not in international waters. But in order to broadcast on those frequencies without a license, you have to do so with an FCC approved marine radio, FCC label on the back of the radio. So all marine radios are factory preset with all the channels up to 48 channels and can put out 100 watts as long as you are using them on water. They are not legal to use on land. If you are on land, you must be trying to contact a watercraft. I went to some of the race radio web sites and they sell 25 watt radios that seem to be spec d-out 2 meter radios. On the web they don't say you don't need a license, but they don't tell you that you do need one either. I don't know how the race series gets around the over wattage, but the consensus with the people I talked to was you need a license and none had heard of an exemption except for what I have listed. I also checked the FCC web site and could not find an exemption, but it is a large web site with lots of links and I just may not have found it. Looking at some of the race series frequencies, I would say they are over powering on the MURS system. The bottom line is if you are going to get a 2 meter radio and broadcast with it, get an amateur radio license. You do not need a license to just listen to the radio or scanner, only if you broadcast.

2 Why get a ham radio? Like it was mentioned earlier they have better sound, less noise, less interference, a lot better range, and a better chance in an emergency to make contact with someone using the repeater system. A 2 meter radio costs more than a CB. Average cost on a 2 meter radio would be $150 to $250, depending on what you want and wattage rating. Some 4 wheel drive clubs have their own line-of-sight frequency. When I was in Quartzsite, AZ, the group that I ran with had a ham frequency that they picked, just like the TRR uses channel 4 on the CB. The only problem for me was remembering how to reset the radio channel to their frequency, so keep the owner's manual close by. Why use a CB radio? No license needed. They are inexpensive, plentiful, and you can buy a replacement at any truck stop. They all have the same channels and frequencies, no programming involved, unlike a ham radio. CB radios are only 4 watts, but with a good, properly tuned (SWR) antenna and cable (recommend RG-58 A/U type coaxial cable) they can work very well. The quality of the antenna can make the difference between a great working radio and one that doesn't. Don't skimp on the antenna. Buy a cheap radio and a good antenna. Aside from added bells and whistles, all CBs are FCC regulated to transmit no more than 4 watts of power. It is illegal to use power amplifiers with CB radios. It is illegal to "tweak" the radio's internal circuits to increase output power. The transmitter power of a legal, FCC certified CB radio is 4 watts AM. A good antenna on an inexpensive radio will almost always outperform a bad antenna on an expensive radio. And remember a CB antenna MUST be properly tuned (SWR) to your radio and vehicle. CB radios operate in the 11 meter band. The reason CB radios are kept at 4 watts is that overpowering a CB will bleed signals in to the Ham 10 meter bands on the low side and also bleed into the Ham 12 meter on the high side. Overpowered CB radios are the ones that sound like they are transmitting from inside a tin can. SWR: In almost every instance, once you get the same SWR reading on channels 1 and 40, further antenna tuning will not improve the readings. If the SWR is still over 2:1, you have other problems to conquer. Exception: There are rare occasions when the ground plane is so small or large that the system is way out of phase (especially with high-performance antennas). If you have high SWR on all channels and have confirmed that you have no opens or shorts in the feedline, try making a small tuning adjustment in the antenna. There are times when the SWR will drop equally across all channels under unusual ground plane conditions. If you find this to be the case, carefully adjust the antenna. SWR that is high on all channels (over 2:1 but not pegging the needle) after the antenna has been tuned usually indicates insufficient ground plane, ungrounded antenna mount or that a coax cable problem exists. You can never buy coax cable that is too good for your system. Never compromise quality for cost when purchasing coax. Your best bet is to stick with coax that has a stranded center conductor and 90% or higher shielding. Excess coax between your radio and antenna mount should never be wound into a circular coil of less than 12" in diameter. Doing so can cause system problems. Your best option for handling excess coax is to serpentine the cable into a 12 to 18 inch yarn-like skein. Secure the skein in the center with a wire tie and tuck it away.

3 Coaxial cable with holes in the outer insulation, severe bends, or door, trunk or hood caused pinches will cause performance problems. Treat your coax with care. When tuning your antenna(s), make sure that you do so with the vehicle doors, hood and trunk closed. If left open, they can cause inaccurate SWR readings. Try to simulate actual operating conditions. FRS (Family Radio Service): These are the small hand-held radios. You do not need a license to operate them, they are easy to use, and all channels are pre-programmed. They are limited to 1/2 watt and have small fixed antennas so their range is very limited. GMRS radios operate in the same frequency bands as FRS but at higher wattage so a license is required. Below is a listing of the different types of radio systems: FRS (Family Radio Service) The FCC does not require a license to use the FRS service. Intended to be used by family and friends to communicate within short distances. For non-commercial use only. Most consumer radios have both FRS and GMRS channels. If you purchase a FRS / GMRS radio you can avoid the need for a license by staying within the FRS channels (usually channels 8-14). All FRS radios are limited to ½ watt of power, and must have a non-removable stubby antenna, so your range is greatly limited. GMRS (General Mobile Radio Service) GMRS is also for individuals and their friends and family. For non-commercial use only. Is a more powerful service for individuals than FRS. GMRS does require a license. Equipment must be certified for GMRS use. LMR (Land Mobile Radio, also PLMR for Private Land Mobile Radio, or Industrial/Business Pool) LMR is for use in business, government agencies, and non-profit institutions such as; education, healthcare, and religious organizations. Most radios approved for LMR usage operate on either VHF ( MHz), or UHF ( MHz) frequencies. Once obtained, the license is good for 10 years. There are several different types of LMR licenses depending on your usage needs. The 3 most common are: o Simplex License - Licenses a set of frequencies within a radius of a single location. o Duplex License - When using a repeater this license includes a frequency pair, spaced for repeater use.

4 o Itinerant License - Allows the use of radios at any location within a state, set of states, or nation-wide depending on your needs. Commercial applications usually require frequent use of channels with minimal interference by other users. An FCC LMR license affords businesses relatively open communication with minimal interference. CB and MURS channels are often crowded. MURS (Multi-Use Radio Service) MURS is an unlicensed service for either business or personal use. Equipment has pre-set frequencies on 5 channels in the VHF 151 & 154 MHz range. Since it is open to everyone the lack of privacy and channel interference may be a problem in a business setting. MURS radios are limited to 2 watts or less, so your talk range is limited. Still, MURS can be a good option for some businesses such as small sites or temporary job sites. Your radio must be MURS certified to use MURS. Ham Radio ( also called Amateur Radio) Ham Radio is a popular passion among many people world wide. Is used by hobbiists and used in emergency situations by volunteers. Requires a licensed to operate communications equipment on the "amateur bands" (or frequencies). There are 3 types of licenses: Technician, General, Extra. You must pass an examination to obtain an Amateur radio license within the US (requires knowledge of radios and electronics). There are many online aids to help you prepare for the test. Once you have a license you can operate on many frequencies that are not available to other users. CB (Citizens Band) Does not require a license in the US. Can be used for either commercial or personal communications. Equipment has pre-set frequencies on 40 channels. Operates on AM modulation with 4 watts of transmit power Frequency range is MHz (Ch 1) to MHz (Ch 40). Since it is open to everyone the lack of privacy and channel interference may be a problem in a business setting. Marine Radio Marine radios are specifically designed for communications on the waterways. The channels on Marine radios have preassigned frequencies, each channel/frequency is designated for a particular type of marine communication. For example, channel 16 is set at frequency HMz and is for distress calls only.

5 It is important that you only use two-way radios specifically approved for marine use when on the waterways. Other VHF radios should not be used because they will not have the proper frequency settings. Today's marine radios have other features such as NOAA weather alert channels. There are basically two types of marine radios: handheld and fixed-mount. o Handheld marine radios are more limited in range, but can be moved from one boat to another. o Fixed-Mount marine radios, just as the name implies are permanently mounted. They deliver more power as they are run off electrical connections on your boat. AirBand Radios Airband radios are used for both navigation and communication. AirBand radios use VHF frequencies in the 108 MHz MHz range. No license is required for individuals. However, aircraft stations do require a license. See the FCC for more details. Use only airband radios for aviation. Aviation radios are not like other VHF radios. Airband radios have specific channel setups and functions used in aviation communications that land-based VHF radios do not have. Since aviation transmissions primarily occur in the air, communication range is much greater for airband radios than land-based VHF radios. So a 5 watt handheld airband radio used in-flight will have a much longer range than a similar 5 watt VHF land-based radio. Panel mounted airband radios, usually 8 watts, have an even greater range. From the air, most airband radios typically have a range of around 200 miles. The information I listed here is just a quick overview. There is a lot more information available. If you are interested in getting your amateur radio license, you can go to the FCC's website or you can check out ARRL at You can also check some local amateur radio clubs. Most clubs can help you get your license. I hope this information helps and that it's not too much information overload on radios. Erwin Greven