As of August 1, 2023, NM4W changed the preferred radio communication method for rides from CB to GMRS. Family Service radios (FRS) share the same 22 channels with GMRS. An FRS radio will also meet the new club standard.
The author will now summarize the available options, pointing out both pros and cons for each type.
FRS The first option is the FRS radio. All FRS radios are small, low-powered handheld radios with small fixed antennas. This was done intentionally to limit the range of these radios and thus limiting the amount of interference they might create. The advantages of this option are: (1) no license is required, (2) they are portable, and (3) they tend to be priced quite reasonably. The disadvantage is limited range and capability.
FRS radios are limited to 2 watts on channels 1-7 and 15-22; 0.5 watt on channels 8-14. FRS radios are not capable of repeater option. Repeater capability only comes with GMRS radios. One must also consider how a particular radio is powered. Some require replaceable batteries, thus requiring the user to keep a supply of fresh batteries on hand. Others employ rechargeable batteries. In this case, the user must be mindful of the charger power requirements. Many of the older FRS radio chargers require 120 VAC. This does not lend itself to powering the unit in most vehicles. Some FRS radios are now starting to come with 12VDC chargers. Be careful to take this into consideration when buying any handheld FRS (or GMRS) radio.
GMRS GMRS radios come in both handheld and base station configurations. Each has its pros and cons. GMRS does require a license. There is no test, but a license does cost $35, is good for 10 years, and can be used by all members of a licensee's immediate family. The procedure for obtain a license is covered in a later section of this document. The advantages of the GMRS option are: (1) higher power output, (2) the ability to use external antennas, thus further increasing range, and (3) the ability to make use of repeaters. GMRS radio operators are also required to identify (transmit their call sign) at regular intervals during a conversation and at the end of a series of transmissions.
Handheld GMRS radios have much in common with FRS radios. Some handheld GMRS radios are capable of somewhat higher power output than FRS. GMRS radios are usually capable of repeater operation. There does not seem to be an appreciable price differential between them and with FRS. Both GMRS handheld and FRS radios tend to come in pairs, although other packaging options are availble. Be careful to order the quantity that desired. Power limits for GMRS are: 5 watts for channels 1-7, 0.5 watts for channels 8-14, and 50 watts for channels 15-22 and for all repeater input channels.
Base Station GMRS radios tend to be capable of much higher power output than with the handhelds and they tend to cost more. Their prices tend to be comparable to that of a good quality CB radio. Their disadvantages are: (1) they are not portable, and (2) they are not capable of operation on channels 8-14. They tend to require 12 VDC power and thus can be powered directly by the vehicles 12 volt battery.
Considerations for choosing a GMRS/FRS Radio
1. Handheld vs. Base Station. If high power is needed, a Base Station GMRS is indicated. A base station unit will provide higher power and will require the use of an external antenna. Both of these attributes allow the base station to "get out" better than any handheld. It should also be noted that the lower power output capability of the various handheld units should be perfectly adequate for 99% of club usage.
2. Mounting is another problem. It is getting harder and harder to find a place to mount a base station radio in these newer vehicles. Some means of securing a handheld radio should be employed as simply laying it on the dash will undoubtedly result in the radio "wandering" around the vehicle interior.
3. Powering a handheld unit is also an issue. Depending on the type of battery employed, the user must either keep a supply of fresh batteries on hand, or have the proper means of powering a battery charger.
4. Licensing. A license is required for any GMRS (handheld or base station) radio. None is not required for FRS. The procedure for obtaining a license is described in the original document.
5. Cost. Handheld units are quite reasonably priced. It is quite possible to obtain a perfectly adequate handheld GMRS or FRS radio for well under $100. Base Station units are more expensive, but are still not unreasonably priced.
6. Repeater Operation. If the ability to utilize repeaters is desired, GMRS is mandated.
A word about repeater operation. When a repeater channel (GMRS only) is chosen, The GMRS radio transmits in the 467Mhz band and receives in the 462Mhz band (Channels 15-22). Repeaters are typically mounted at locations higher in elevation than most of their surroundings. They receive the 467Mhz output from the GMRS radio and then re-transmit it on the normal 15-22 462Mhz channels. These re-transmissions are typically at a much high power level than that of the users GMRS radio. This allows communication over a much longer range than would otherwise be feasible. FRS radios can listen to these repeater outputs, but they are incapable of the necessary output for the repeater input.
Usage Considerations
Many club members have already purchased base station GMRS radios which are incapable of operating on channels 8-14. Therefore, ride leaders should refrain from designating these channels for use on a club run.
According to convention, channel 20 is designated as a "calling" channel. Therefore, it would be good practice not to use this channel for a club run.
It should also be remembered that GMRS users are required to identify at regular intervals during an extended conversation and at the end of a series of transmissions.
September 2022 Document
There are currently three different radio types commonly used by the 4-wheeling community. These are:
- Citizen’s Band(CB)
- Amateur Radio(Ham)
- General Mobile Radio Service(GMRS)
Years ago CB was the only practical option for 4-wheelers and thus has been the standard for many years. Ham radio became a more attractive option after the creation of the “No Code” Technician License in 1990 and the elimination of all Morse code requirements in 2007. The higher power and the ability to use repeaters allow communication over longer ranges than is possible with CB. These facts act to make Ham radio an attractive option. The higher cost and complexity of ham radio equipment, plus the testing requirement, have acted to greatly restrict ham radio popularity.
GMRS has been around since the early 1970s, but has only recently started to gain traction with the 4-wheeling community. GMRS retains much of the simplicity of operation of CB, with the greater range and quieter operation of Ham radio. These factors combine to make GMRS an attractive alternative to CB. Several organizations, notably Jeep Jamboree among others, have started mandating GMRS.
Citizen Band
Advantages: Most 4-Wheelers already have one. They are cheap, easy to operate and require no license.
Disadvantages: Power output is limited to 4 watts, thus limiting their useful range. They are noisy due to their use of AM (amplitude modulation). The size of the antenna needed for this frequency range (27 Mhz), makes them quite unwieldy, leading to compromises in design and thus, less than ideal performance. Most commonly available CB antennas are less than the ideal ¼ wavelength (108 in) long, finicky to tune and are still large enough to require removal and/or lowering before parking the vehicle in a standard garage.
CB radio reception tends to be significantly noisier than with Ham or GMRS radios. This is largely due to CB’s use of Amplitude Modulation (AM) where the strength of the transmitted signal is varied in step with the audio signal.
Ham radios (those commonly used in the 2 meter and 70 cm bands), GMRS and FRS radios all employ Narrow Band Frequency Modulation (NBFM). Here the frequency of the transmitted signal varies in step with the audio signal. Most noise is AM in nature. FM receivers are largely insensitive to amplitude variations and thus they tend to reject “noise” resulting in much quieter operation.
There is another article, “CB Radio 101” on the NM4W.org website. That article contains much information concerning CB radio selection, antenna selection and tuning, etc… That information will not be repeated in this article.
Amateur Radio
Amateur Radio encompasses many bands with frequencies just above the AM broadcast band to well into the Microwave region. The Ham bands most commonly used by 4-Wheelers are the 2 meter band (144 to 148 Mhz) and to a lesser extent the 70 centimeter band (420 to 450 Mhz). This discussion will be confined to the characteristics of these bands and to no others.
Advantages: Much higher power output is possible along with the ability to use repeaters to further increase range. Ham radios, suitable for mobile usage, typically are capable 50 watt power levels. The shorter wavelengths, at these higher frequencies, allow the use of smaller and more efficient antenna designs.
Disadvantages: The much higher cost and complexity of ham radio equipment, plus the fact that one must pass a test in order to obtain a license, all contribute to limited usage within the 4-Wheeling community. For those who may be interested, only the lowest level ham license (Technician), is required to operate ham radios in the VHF and UHF ranges (above 50 Mhz). This includes the bands most commonly used by 4-Wheelers. The test for that license is relatively easy to pass.
General Mobile Radio Service
GMRS and the Family Radio Service (FRS) are closely related. They share the same 22 channels operating in the 462 and 467 Mhz bands. Because they share the same 22 channels and the same transmission mode (NBFM), FRS and GMRS radios can communicate with each other.
FRS radios are all small, handheld, low power units and are required to use small non-removable antennas. These restrictions are designed to limit the amount of interference they could possibly create.
GMRS radios are allowed much higher power output levels (on certain channels, 15-22), external antennas, and have the capability to use repeaters. Channels 1-7 and 15-22 operate in the 462 Mhz band, while channels 8-14 and the repeater inputs, channels 15R-22R, operate in the 467 Mhz band. These frequencies, and the associated short wavelengths, allow the use of quite small antennas. A GMRS ¼ wave whip antenna is only approximately 6 inches long.
The 22 GMRS channels are divided into three groups, with each group having different restrictions.
| Channel | FRS Power Limit | GMRS Power Limit | Notes |
|
1-7 |
2 Watts |
5 Watts |
|
|
8-14 |
½ Watt |
½ Watt |
Handheld Only |
|
15-22 |
2 Watts |
50 Watts |
|
|
15R-22R |
NA |
50 Watts |
Repeater Inputs |
Because channels 8-14 are restricted to handheld radios only, base station GMRS radios do not operate on these channels. Only handheld GMRS and FRS radios can use them. Many club members have purchased base station radios, thus channels 8 through 14 should not be specified for use on a club run. Further, channel 20 has been designated as a "calling" channel and thus should not be used for a club run.
Repeaters
There are several GMRS repeaters in the Albuquerque area and throughout New Mexico. Permission from the repeater owner must be obtained in order to use them. The author Googled "GMRS Repeaters Near Me" and found two websites where permission to use local GMRS repeaters can be requested. The author has requested permission using the gmrsnm.net on two occasions with noresponse. The author has also requested permission on the swcrs.org website and was almost immediately granted access. The recommendation is to use the swcrs.org site and forget the other one. Before requesting permission, one must first obtain a GMRS license. The procedure is described in the Licensing paragraph.
When Channels 15R-22R, the repeater input channels are selected, the GMRS radio transmits in the 467 Mhz band and receives in the 462 Mhz band – exactly 5 Mhz below its transmitter signal. The repeater receives and transmits on the opposite bands. Repeater usage almost always requires the use of "privacy" codes.
CTCSS & DCS "Privacy" Codes
These codes have long been used within the ham radio community and are now being used within the GMRS community. In both cases, they are primarily used for repeater access. The use of these codes will be new to CB radio users as their usage is not possible with CB.
It is a misnomer to call these "privacy" codes as they do not make ones transmissions private. Anyone, listening on that channel, will be able to hear your transmissions even though a privacy code is employed, provided that these other listeners have selected no privacy encoding. These codes can be used within a group to insure that only transmissions from others, within that group, will be heard. The main usage of privacy codes is for repeater operation as most repeaters require a certain code be used to "unlock" that repeater.
When either a CTCSS or DCS code has been programmed for a certain channel, that code will be embedded in all transmissions on that channel. Further, that same code will be required on any received signal, if it is to be heard. If that particular encoding is not detected in a received transmission, the squelch will not be "unlocked" and the user will not hear that transmission. If any of these codes is selected, all members of a group must select the same encoding in order to hear each others transmissions.
Continuous Tone Coded Squelch System (CTCSS) encoding embeds a continuous, subaudible tone in all transmissions and requires that tone be present in any received signal in order to unlock the squelch thus allowing that signal to be heard. There are a total of 38 possible CTCSS codes. These codes are also commonly referred to as "Private Line" PL codes. CTCSS and PL are two names for the same encoding.
Digital Coded Squelch (DCS) encoding embeds a certain, digitally encoded numeric sequence in all transmissions and requires that same encoding in all received transmissions. These codes are sometimes called "Digital Private Line" or DPL codes. There are 104 possible DCS codes.
It is recommended that club members only use these codes for repeater access. If a trip leader were to select a CTCSS or DCS code for the channel selected for a given run, all radios, on that run would have to be programmed for that usage. That programming is not nearly as simple as just changing channels. Such a selection would undoubtedly lead to much confusion with no offsetting benefit. Don't do It.
Repeaters typically require one of these codes be used to "unlock" that repeater. When a user is granted access to a certain repeater, that user will then be given the required encoding. The owners manual for a particular radio will give specific instructions for programming the radio to use CTCSS and DCS codes.
Race Radio
Race Radio is a term commonly applied to radios sold by such vendors as Rugged Radio, etc… It is not a term defined by the FCC and thus has no definitive definition. This term is commonly used to describe radios used during the “King of the Hammers” and other such events.
The Land Mobile Radio Service, an FCC defined term, includes commercial licenses (commonly referred to as “Business Band”) that are issued for business usage with that usage being restricted to a 75 mile radius of the surrounding the licensee’s location. These licenses authorize use on specific frequencies and are only legally used by those affiliated with that business and within that 75 mile radius. King of the Hammers and the Mile Hi Jeep club (among others) have obtained such licenses for use during their events. The Mile Hi Jeep Club supplies radios to All-4-Fun participants and cautions that these radios cannot be legally used more than 75 miles from the All-4-Fun location.
It appears that some vendors program cheap Chinese radios with frequencies licensed to the King of the Hammers event and then sell them as “Race Radios”. It is perfectly legal to listen to any communication with these radios, but it is strictly illegal for anyone not affiliated with the licensee to use them for two way communication, or for anyone to use them more than 75 miles from the Johnson valley where the King of the Hammers event is held. It should be noted that if one is caught transmitting on an un-authorized frequency, that person can be subjected to a $10,000 fine. Buyer Beware!
Licensing
Neither CB nor FRS radios require a license. Ham and GMRS radios do require them. Licenses are obtained from the Federal Communications Commission (FCC). In order to obtain a license, one must first obtain an FCC Registration Number (FRN). The following link will allow a new user to establish login credentials and obtain an FRN: https://apps.fcc.gov/cores/userLogin.do. The FRN should be retained by the user and then used for all futther communication with the FCC.
Once an FRN is obtained, the following link can then be used to apply for a license: https://wireless2.fcc.gov/UlsEntry/licManager/login.jsp. One must first login, using the previously obtained FRN and password. The next screen will have a menu on the left side. The top entry is “Apply for a New License”. The next screen then asks “Select Service”. The various services are identified by two letter codes. The GMRS is code ZA and is located at the very bottom of the list. From thereon, simply follow the prompts to finish the application and pay ($35) for the license. After approval the FCC will email the license which is good for 10 years and can be used by all members of the licensee’s immediate family.
Ham licenses are also obtained by a similar process and also cost $35 and are also good for 10 years. Evidence of passing the appropriate test must also be submitted. Ham licenses can only be used by the licensee him/her self. Each operator must be individually licensed. To obtain a Ham license, one must first pass the appropriate test. Tests are administered by Volunteer Examiners (VE). There are several local Ham Clubs that regularly hold testing sessions. The usual fee for testing is $15.
Antenna Selection, Installation, etc…
A proper antenna system is necessary if any radio is to perform optimally. This means that the coax used to connect the radio to the antenna must match the impedance level of the transmitter output (almost always 50 ohms), and the antenna needs to match that impedance level at the transmitting frequency. If these conditions are maintained, most of the power output from the radio will be radiated and the signal should “get out” well. If there are any impedance mismatches in the system some power will be reflected back to the transmitter and will not be radiated. The worse the mismatch, the more power will be reflected. If the mismatch is bad enough, it is possible that enough power could be reflected back to the radio to actually damage the transmitter output circuitry. This is why no transmitter should ever be keyed (activated) without first connecting an appropriate antenna system.
As stated earlier, the coax used to connect the radio and the antenna must match the impedance level of the transmitter output (50 ohms). Most any 50 ohm coax will work, although the use of higher quality (lower loss) coax becomes more important with GMRS. Transmission line losses do increase with increasing frequency. The question of whether the coax used for an existing CB radio, can be used with a GMRS radio will certainly come up. The answer is that yes, it is permissible. If this were to be done, the connector at the antenna end almost certainly would have to be changed as most CB antennas employ the PL-259 style connector, while most VHF/UHF antennas use the New Motorola Mount (NMO). This would include most GMRS (and Ham) antennas.
Antenna selection is quite important. It is imperative that an the antenna be designed for the frequency of the transmitter output. As stated earlier, for maximum power transfer, the impedance of the antenna must match that of the transmission line (the coax). Antennas only present the proper impedance at the frequency for which they are designed. At other frequencies, the antenna will likely present a very different impedance level to the coax, resulting in a very serious mismatch. Some have questioned about the permissibility of simply using an existing CB antenna with a GMRS radio. Don’t do it. A very serious impedance mismatch will be the result and most of the power will be reflected back to the radio.
It should be noted that if a serious impedance mismatch occurs with any transmitter, be it CB, Ham or GMRS, performance will definitely be compromised. If this were to occur at a high power setting, it is possible to damage or destroy the transmitter.
When an antenna is mounted on a motor vehicle, that vehicle then becomes part of the antenna system and will affect the operation of said antenna. Therefore, selection of the antenna mounting location is important. The ideal location would be one where the antenna would be mounted in the middle of a large flat metal surface with no other objects in close proximity. This really isn’t practical, considering the design of most Jeeps. Therefore, antenna mounting will always involve some level of compromise. Best results will probably be obtained by mounting the antenna reasonably high and away from other objects. Common mounting locations are the spare tire carrier at the back of the Jeep and on the front fenders. Both locations have been shown to give acceptable results.
The vehicle’s effect on antenna performance is more pronounced at the longer wavelengths employed by CB radio. Thus, the better CB antennas provide a means by which they can be tuned for optimal performance. This should be done as described in the “CB Radio 101” article. Most GMRS antennas have no such provision, making their installation much more of a “plug and play” operation.
Summary
GMRS is continuing to increase in popularity in the 4-wheeling community. It retains most of the advantages of Ham Radio and the simplicity of CB Radio, while avoiding most disadvantages of both CB and Ham Radio. None of the radio types considered here are suitable for long range communication unless repeaters are employed. The higher power and more efficient antenna designs possible with GMRS should allow communication over longer ranges than possible with CB. The use of NBFM modulation should also alleviate the necessity of constantly "fiddling" with the squelch control that is so common with CB. GMRS radios are priced similarly with CB radios, but definitely far less costly than ham radios.
The author believes that GMRS will, at some time in the future, replace CB as the standard for communication among most 4-Wheelers, as is now the case with New Mexio 4-Wheelers.