What is the Typical Communications Range?
At 460 MHz, communications range is determined primarily by the height of the antennas and the nature of the surrounding countryside. Raising the height of the antenna from 4 feet above ground (the height of a typical car roof) to 30 feet above the ground can extend the communications range by as much as 300% or more. > For Mobile-to-Mobile Communications
For a typical 2- to 4-watt handheld transceiver, the communications range directly to another comparable handheld unit is typically in the range of 1/2 mile to 1 mile. In rolling or heavily forested terrain, the range can be less. If the two units are on distant mountain tops with a clear "line of sight" contact, this range could be much further. > For Base-to-Mobile Communications
A 10-watt base station with an antenna atop a two-story building may have a 5- to 10-mile communications range with a 4-watt mobile unit. This range could be somewhat more in flat terrain or if the building is on a hill. UHF "line of sight" communications will go further in a flat countryside than in a rolling one. Signals can also bounce off of tall building surfaces. This can actually increase range in some urban or mountainous environments. Increasing the transmitter power at both the base station and the mobile unit can increase the communications range slightly. However, the primary way to increase operating range is to increase the base station antenna height. > For Repeater-Assisted Communications
A typical low-power handheld radio might be able to communicate with a base station on top of a mountain or a tall building 15 miles to even 30 or more miles distant. A repeater station is really just a special kind of base station which employs a very tall antenna. The repeater usually receives on a 467 MHz GMRS frequency. When it receives a signal (usually accompanied by a special code which this repeater listens for especially), the repeater then automatically (i.e., without further operator action or control) retransmits that same signal on the comparable 462 MHz frequency. Another kind of repeater, only recently introduced to GMRS, receives a signal on a 462 MHz frequency, and retransmits that same signal after a slight time delay on that same frequency. This kind of repeater can be much less expensive to purchase and operate, since it doesn't require a "duplexer" or a second antenna for receiving purposes. However, like a conventional repeater, this "store-and-forward"-type repeater still requires a control method to shut it down, if it is operated from a remote location. The advantage of the repeater is in its capability to receive a signal from a distant transmitter, and to retransmit a signal which can be heard by a distant receiver, because of the station's greater antenna height. If a repeater with a tall antenna can hear a mobile signal 20 miles away (a typical distance for a well-sited repeater), then it can usually transmit to another mobile unit anywhere within that same 20-mile radius. The two mobile units themselves do not need to be near each other. They could be at opposite sides of the 20-mile radius of coverage of the repeater, or 40 miles apart from each other, and still be able to communicate through the repeater. There are some practical upper limits on range. For example, a repeater whose antenna is mounted on a 100-foot tower in mostly flat terrain might cover a 15-mile radius. An additional 5 to 10 miles of coverage might be gained by each doubling of antenna height. Using this example (and with the same typical terrain), mounting the antenna on a 200-foot tower might provide a 25-mile radius of coverage. But to achieve a 35-mile radius, you would need a 400-foot tower. For a 45-mile radius of coverage, you would need an 800-foot tower. From this example, you can see that extending the range beyond 25 or 30 miles can come only from having access to a very tall antenna or (more likely) to a mountain top. Although there is the obvious advantage of additional communications range in communicating through a repeater station, there are also disadvantages. When one repeater is transmitting, it can block out or interfere with all other communications on that same frequency within that same area. Since there are only eight frequency pairs available for repeater communications, GMRS users must cooperate in sharing the use of these frequencies. One method of cooperating is to use the repeater only when it is necessary to employ its extended range. When the corresponding units are close enough to each other so that the repeater is not needed, then the units should communicate with each other directly, not through the repeater. Repeater users should also keep their communications as short as possible (namely, only necessary and urgent communications). Furthermore, because signals retransmitted through a repeater travel much further, they are less private. Privacy is another advantage of shorter range "direct" communications. Is There a Height Limit for GMRS Antennas?
The only height limit in the GMRS applies to "small" base stations and "small" control stations. Repeater stations and conventional base stations have no antenna height limit, at least insofar as the FCC is concerned. However, if an antenna structure extends more than 200 feet above ground, or if it is located within about 6 miles an airport, then there are FAA (Federal Aviation Administration) requirements for painting and lighting. If the antenna structure extends more than 300 feet above ground, there are also special provisions for determining the impact on the environment. In most areas, of greater concern will be the height limits imposed by local zoning regulations and (if applicable) restricted-use covenants. Even the 20-foot height permitted "small" base and control stations may exceed local zoning ordinances! HINT: If your are a HAM then there exists documents from the ARRL that will help in putting up high towers and if you happen to have a GMRS antenna at the top of that tower for your GMRS repeater well ~~ PROBLEM SOLVED ~~ 
PRB-1, cited as "Amateur Radio Preemption, 101 FCC2d 952 (1985)," is a limited preemption of local zoning ordinances. http://www.arrl.org/FandES/field/regulations/local/prb-1_program.html What About Communications Quality Within That Range?
GMRS signals are at UHF frequencies, and have a wavelength of about 25 inches. CB signals are at HF frequencies, and have a much longer wavelength (about 36 feet). This shorter wavelength enables GMRS signals more easily to penetrate into and to escape from buildings. The optimum location when inside a building, however, is on an upper floor near a window with an outside exposure facing the desired direction of communication. Do GMRS Signals Suffer From "Skip"?
The "skip" phenomenon commonly encountered with CB signals, especially during peak sunspot conditions, does not affect UHF frequencies. However, there are other phenomena which can extend or diminish UHF communications range. The most common of these is atmospheric reflection caused by thermal inversions, for instance as occur over large bodies of water (such as the Great Lakes or along the Atlantic Seacoast). Although these inversions occur only occasionally, they can still cause distant signals to interfere with local signals. Fortunately, most GMRS personal users respect each others' communications needs. GMRS licensees usually try to cooperate to minimize problems during these "enhanced propagation" conditions. "DX'ing" distant GMRS stations is usually not appreciated -- indeed, it is a virtual guarantee to become unwelcomed to use others' repeaters! A good way to tell if UHF signals are being extended by atmospheric conditions is to view the lower UHF TV channels (14 through 20) with an outside TV antenna. If you can see distant TV stations that are not normally available in your local area, then there may be atmospheric conditions that are extending propagation. How Expensive Is GMRS?
Only commercial-quality radios FCC type-certified for GMRS may be used in the GMRS. The cost of GMRS radios has decreased in recent years, both as the quantity of used equipment has increased, and as the number of manufacturers offering less expensive models has increased. Low-power GMRS handheld transceivers have also recently become available through many local consumers electronics stores and from mail-order vendors, including through the Internet. However, many of these radio models are capable only of unit-direct-to-unit communications, and cannot operate through a range-extending repeater. To be capable of operating through a conventional repeater, a GMRS radio must be capable of transmitting in the 467 MHz band (as well as receiving in the 462 MHz band), and must be able to transmit subaudible control tones. However, even GMRS radios that cannot transmit on the 467 MHz GMRS frequencies can communicate through the recently introduced "store-and-forward"-type repeaters (that receive instead on the 462 MHz GMRS frequencies). More information on this new kind of repeater will be in our subscription newsletter, the "Personal Radio Exchange." The cost of a GMRS transceiver will depend on a number of factors. The primarily factor may be the source of the radio. Mass-produced radios sold through mail-order vendors or local consumer electronics stores are likely to be less expensive than identical models sold by local two-way radio dealers. Other aspects that can affect the cost of a radio include the transmitter power, the number of channels, and the presence or optional availability of subaudible tone signaling (which is usually necessary to communicate through a repeater station). New radios for base or mobile use can typically cost from $50 to over $3000. A common price range for an "entry level" handheld transceiver with full channel and signaling capabilities is $150-$300. Some "bubble pack" radios (so called because they are packaged in a "blister pack") sold at consumer electronics stores are available for even less, often combined with a capability to communicate on FRS channels as well. (However, most such "bubble pack" radios are not capable of transmitting on the GMRS 467 MHz frequencies, and are thus not capable of communicating through conventional GMRS repeaters.) The PRSG has prepared a publication, "How to Choose a Handheld GMRS Radio." This publication ($6) and others in our "Basic Information Series" are available from our Michigan office. A conventional repeater station (with its accompanying hardware, control circuits, filters, etc.) can cost anywhere from $1200 to over $8000. BridgeCom CS-540U Repeater <<< Click on to see a BridgeCom Repeater 
However, a single repeater can be used by many individuals, and local "user cooperatives" are becoming increasingly popular. The recently introduced "store and forward" repeaters can usually be assembled for less, typically for as little as $20 to $50 above the cost of a simple base station and antenna, plus (if necessary) the cost of some method of remote control. Build Your Own Repeater <<< Click on to see how to build your own repeater With appropriate long-term financing, a 30-member cooperative can purchase, install, and maintain a conventional repeater frequently for less than $5 per member per month for the equipment, exclusive of the site rental expenses. (That compares with fees ranging anywhere from $25 to $100 or more per month which many commercial licensees pay for the use of comparable business- and industrial-use repeaters.) Despite the high cost of the repeater equipment, the greater cost over the long run can actually be that of renting a favorable antenna site. In the major urban areas, prime sites (on the tallest buildings) can go for as much as $400 to $800 or more per month. It doesn't take many months for that to build to a gigantic bill! A repeater cooperative may be able to find less expensive prices. In a city of many hills, a member of the cooperative may live near an advantageous hilltop, for instance. The members of many GMRS user-cooperatives perform volunteer services for local public safety agencies, hospitals, school districts, etc. These working relationships can provide an avenue for acquiring low- or no-cost access to less advantageous but still acceptable repeater sites. If all else fails, access to a favorable antenna site may be available for rent from an established communications vendor. However, there can be "strings attached." You could find yourself locked into a requirement to purchase your radios from just that particular vendor (a common tactic used by two-way radio dealers), in exchange for being permitted the use of that repeater station or that site. This can restrict your option to purchase less expensive but adequate radios from some other source. Note: Many a good 15-25 mile radius GMRS Repeater are operating on personal Ham Radio Towers some no more than 50' tall. See above "HINT" to learn how to put up a Ham Radio Tower. With the Morse Code being dropped for an Amateur Radio Ham License it is easy to become an Amateur Radio Operator these days. 
http://www.hello-radio.org/ <<< CLICK ON FOR THE ARRL "HELLO" SITE How Do I Proceed with GMRS?
If, after weighing the various advantages (the generally courteous operation from other personal licensees, the high quality of communications, etc.) against the various disadvantages (the sometimes high cost of the equipment, the limited range without a repeater, etc.), you wish to proceed with GMRS, you should take the following steps:
How Do I Contact Local GMRS Users?
Before investing in radio equipment, you may want to contact other GMRS users in your area whose communications uses and needs may be similar to yours. The PRSG publishes the GMRS National Repeater Guide, which also contains the names, addresses, and phone numbers of many local and regional "user cooperatives" and others (especially current GMRS personal and public service team licensees) who may be able to assist you. They can frequently answer more of your questions about existing local operations, and give you some good hints (and maybe even some warnings!) about local sources of equipment and repeater services. How Do I Decide on My Channels?
The FCC Rules now permit GMRS personal licensees to operate on any GMRS channel. (See above Table 1.) The application form (FCC Form 605) doesn't even ask you for your operating channel or station location. However, you may transmit on the GMRS 467 MHz frequencies only to communicate through a repeater. Most GMRS users regularly operate only on one or two channels. If you intend to use a radio that is capable of operating on only a limited number of channels, and if you are going to use the GMRS to communicate with others already licensed or planning shortly to license in this service, then you will want to choose the same channel(s) that they have chosen or will choose. If not, you will want to choose a channel which is not already in heavy use in your area. The best way to determine which GMRS channels are already in use in your area is to monitor them with a scanning receiver. However, most scanners are substantially less sensitive than typical GMRS radios. Therefore, listen from several different locations from within your anticipated operating area, and use an external antenna, preferably one mounted on the building roof for best reception. In most major urban areas, it is unlikely that you will find a regular GMRS channel which is completely unused. The "675 channel" (see above Table 1) is used by many public service teams and user cooperatives for their emergency and travelers assistance communications. There is a growing nationwide network of repeater stations available on this particular channel for just this purpose. However, GMRS personal licensees may operate on any GMRS channel, and all users must immediately yield to any bona fide emergency communications. Who is Eligible to Obtain a GMRS License?
Only an individual person*** is eligible to obtain a new GMRS license, or to significantly modify an existing one. He or she must be at least 18 years old, and may not be the representative of a foreign government. Prior to 1989, any legal entity (a corporation, an association, a partnership, or a governmental agency) was also eligible to license in the GMRS to operate on these frequencies. An entity which was first licensed prior to July 31, 1987, and which has not significantly modified its operations since then, is "grandfathered" and may continue to operate and to renew its GMRS license(s). However, these grandfathered entities are not permitted to use the "split" frequencies (see aboveTable 2), and may otherwise operate only under the terms (specifying channels, station locations, etc.) on their last license issued prior to July 31, 1987. In some places (especially in the larger urban areas), these "grandfathered" non-personal licensees still predominate on the GMRS channels, although most are expected eventually to move to more appropriate Part 90 commercial and industrial radio services. ***Special Note: The "individual person" obtains the license but everyone in their family may operate under that one license. See "Who Will Be Eligible to Operate Under My GMRS License?" below. All GMRS licensees must cooperate in the selection and use of the assigned frequencies. For more than two decades the FCC has cautioned commercial and industrial GMRS licensees that they must cooperate with personal/family users. The FCC further advised these entities that if they did not wish to cooperate with personal licensees, they should instead relicense for one of the other private land mobile radio services. (The PRSG can provide you with a copy of this important 1977 FCC Public Notice.) The GMRS is not "the other business radio service," the FCC emphasized in adopting new GMRS rules effective in 1989. This change in eligibility reflected in part these entities' continuing lack of cooperation with personal licensees. The FCC expects many current commercial and industrial licensees eventually to relicense and to relocate to one of those other Part 90 "private land mobile" services. Where cooperation problems remain, the PRSG will assist local GMRS personal licensees in identifying the sources of these improper operations. The PRSG can also assist in preparing the necessary information for complaint actions to be filed with the FCC. How do I Obtain a GMRS License?
Unlicensed operation of a GMRS transmitter, including on the "split" frequencies shown above in Table 2 (except by FRS radios), is punishable by a monetary fine of up to $10,000 for the first offense, even more for subsequent violations. You must obtain an FCC license (or be an immediate family member of someone who is already licensed) before you may transmit with a GMRS radio. To apply for a GMRS license, you must complete and return a Form 605 to the FCC. You can obtain a copy of the FCC Form 605 and its instructions by calling: 1-888-CALL-FCC. You can also obtain a copy from the FCC's Web site: www.fcc.gov/formpage.html You can also apply for a GMRS license directly on the Web. This is actually the preferable way to obtain a new GMRS personal license. For more information on licensing, click here. Applicants must also submit an FCC Form 159 ("Remittance Advice"). It is available from the same sources mentioned above. The cost of obtaining an FCC license in the GMRS is $80. Who Will Be Eligible to Operate Under My GMRS License?
A licensee's immediate family members are eligible to operate under his or her license. This includes parents, grandparents, children, grandchildren -- basically you, your spouse, and all of your and your spouse's immediate blood relatives. Others (your employees, friends, associates, etc.) must each obtain their own licenses before they can operate in the GMRS, even if they are just operating one of your own radios. You may not lend your license to any other party. Where Can I Purchase GMRS Equipment?
GMRS radios (often combined with FRS radios, and sometimes mistakenly marketed as FRS-only radios not needing a license) are commonly available from most consumer-electronics stores nationally, and from a variety of sources advertising on the Internet. However, most of these radios at consumer-electronics stores are capable only of unit-direct-to-another-unit communications, and cannot communicate through conventional GMRS repeaters because they lack the capability of transmitting on the GMRS 467 MHz frequencies. (See Table 3 above.) Even if not capable of using a conventional repeater, these radios would still be capable of communicating through the recently introduced "store-and-forward"-type of repeaters. WADSWORTH SALES has BridgeCom Repeaters >>> http://wadsworthsales.com/bridgecom.aspx and soon will have the new Holzberg Mobile >>> http://wadsworthsales.com/holzbergmobile.aspx for General Mobile Radio Service.
Is Used Equipment Available?
A particular problem exists with purchasing used radio equipment. It can be difficult to obtain accurate estimates of repair and maintenance costs, or even just the expense of the initial setup. GMRS radios, but especially used radios, are certainly not "plug and play" hardware. Complex UHF-FM radio equipment can require substantial "shop time" (typically at anywhere from $40 to $80 per hour for labor!) to rebuild or to retune, above and beyond the cost of recrystaling or reprogramming for different channels. These high "shop time" rates may actually be quite reasonable when you consider that a well-equipped two-way-radio repair shop probably has in excess of $100,000 worth of test equipment which it must purchase and maintain. In addition, each individual technician probably needs his or her own bench equipment, at an additional $6,000 to $30,000 per person. As a general rule, you should not consider the purchase of any used GMRS radio equipment unless you have a local technician who is willing to perform the maintenance work, and who already has some experience working on that particular make and model. A good "rule of thumb" is that you should be prepared to spend from 5% to 10% of the original purchase price per year on equipment maintenance and repair costs. For radios more than five to eight years old, you may need to double that estimate. In addition, remember to plan for extra expenses to cover insurance and accidental damage. The typical "blister pack" radios now predominating at most consumer-electronics stores are generally "throw-away" units that are not cost-effective to repair or modify. One hard drop and it could be permanently dead. The irony is that if you seek a durable GMRS radio capable of operating through the expanding national network of conventional repeaters, you should probably consider purchasing a commercial-grade radio, one not advertised as a GMRS-specific radio! Many models currently being marketed as GMRS-specific are often cheaply built, incapable of operating through conventional repeaters, and cannot be cost-effectively repaired, maintained or modified. What Are "User Cooperatives"?
In some areas, persons interested in or licensed for GMRS operations have combined their resources and purchasing power to put up a local conventional repeater station. There are other potential benefits as well to such local user cooperatives. Obtaining information about local, inexpensive yet reliable sources of equipment is another topic about which you should contact other local users or user cooperatives. They may have had especially good or even bad experience with certain local two-way shops. The PRSG's GMRS National Repeater Guide can be a good starting point for identifying local user cooperatives and initiating these contacts. Where Can I Find Out More About the GMRS Rules?
The PRSG continuously updates the FCC Rules pertaining to GMRS, FRS and MURS (Multi Use Radio Service, a new, license-free 150 MHz CB service). For the latest information >>> http://www.provide.net/~prsg/rules.htm
 PL, an acronym for Private Line, is Motorola's proprietary name for a communications industry signaling scheme called the Continuous Tone Coded Squelch System, or CTCSS. It is used to prevent a repeater from responding to unwanted signals or interference. Tone Squelch is an electronic means of allowing a repeater to respond only to stations that encode or send the proper tone. In other words, if a repeater is set up to operate only when a PL tone of say, 136.5hz is heard by it's receiver, then it will allow the transmitting station access. If your station, (your mobile, base or handheld) does not transmit the tone when you key up, then the receiver of the repeater does not hear you and will not be usable by your station until you set the tone in your radio. Any station may be set up to transmit this unique low frequency tone that allows the repeater to operate. If a repeater is "In PL mode" that means it requires a CTCSS tone(PL tone)to activate the repeater. Due to severe congestion of repeaters in some areas, most repeaters are PL'ed.
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Features/Benefits • Fiberglass construction protects radiating elements in corrosive environments. • Copper radiating elements minimize possibility of intermod generation. • Full 10 dB gain – provides maximum on horizon coverage. Technical Features | Frequency Band | 300-699.9 MHz | | Horizontal Pattern | OmniDirectional | | Antenna Type | Fiberglass Omni | | Electrical Down Tilt Option | Fixed | | Gain, dBi (dBd) | 12.1 (10) | | Frequency Range, MHz | 460-470 | | Connector Type | N Female | | Connector Location | Bottom | | Mount Type | Fixed | | Electrical Downtilt, deg | 0 | | Orientation | Upright | | Mounting Hardware | 46 Clamp Set | | Rated Wind Speed, km/h (mph) | 160 (100) | | Gain (Omni), dBi (dBd) | 12.14 (10) | | VSWR | < 1.5:1 | | Vertical Beamwidth, deg | 7 | | Polarization | Vertical | | Maximum Power Input, W | 500 | | Lightning Protection | Direct Ground | | 3rd Order IMP @ 2 x 43 dBm, dBc | -130 | | Impedance, Ohms | 50 | | Overall Length, m (ft) | 5.94 (19.5) | | Element Housing Length, m (ft) | 5.3 (17.4) | | Mounting Pipe Diameter, m (in) | 0.07 (2.75) | | Support Pipe Length, m (ft) | 0.61 (2) | | Weight, kg (lb) | 11 (24) | | Radiating Element Material | Copper | | Element Housing Material | Fiberglass | | Support Pipe Material | Aluminum Alloy | | Max Wind Loading Area, m² (ft²) | 0.174 (1.87) | | Survival Wind Speed, km/h (mph) | 200 (125) | | Bend Mom @ Rated Wind 1" Below Top of Mt Pipe, N m (ft lbf) | 884 (652) | | Wind Load - Side @ Rated Wind, N (lbf) | 333 (75) | | Shipping Weight, kg (lb) | 21.8 (48) | | Packing Dimensions, HxWxD, mm (in) | 7320 x 100 x 100 (288.18 x 3.94 x 3.94) | | Packing Dimensions - HxWxD, m (ft) | 7.32 x 0.1 x 0.1 (24 x 0.33 x 0.33) | | Shipping Dimensions of Accessory - HxWxD, m (ft) | Packed w/antenna | | Shipping Mode | Common Carrier |
 
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Multi-Use Radio Service (MURS)The Multi-Use Radio Service is a low power, short range VHF Citizens Band service in the 150 MHz band. To review frequently asked questions about the MURS. >>> http://www.provide.net/~prsg/murs_faq.htm The FCC created MURS in Fall 2000. To view a summary from the Federal Register concerning the creation of the service. >>> http://www.provide.net/~prsg/mursrno.htm The MURS operating rules are available here >>> http://www.provide.net/~prsg/mursrule.htm The original version became effective November 13, 2000. The FCC recently (November 12, 2002) implemented certain changes, in response to several Petitions for Reconsideration. We have annotated these rules to describe the significance of certain portions. MURS is only now beginning to receive wide publicity. This new personal radio service has the potential to become very popular, especially in the traveling community. Although there are limitations on transmitter power output and antenna height, there are no restrictions on the use of external antennas. This means that the range for vehicle-to-vehicle communications with MURS can much greater than that for FRS (Family Radio Service). As a VHF Citizens Band service, you do not need an FCC license to operate a MURS station. PRSG was the first national organization or publication to announce the FCC's intention to create the MURS. 
MULTI USE RADIO SERVICE ~ MURS FREQUENCY CHART
PL, an acronym for Private Line, is Motorola's proprietary name for a communications industry signaling scheme called the Continuous Tone Coded Squelch System, or CTCSS. It is used to prevent a base station (or mobile/portable) from responding to unwanted signals or interference. Tone Squelch is an electronic means of allowing a base station to respond only to stations that encode or send the proper tone. In other words, if a base station is set up to operate only when a PL tone of say, 136.5hz is heard by it's receiver, then it will allow the transmitting station access. If your station, (mobile, base or handheld) does not transmit the tone when you key up, then the receiver of the other base station (or mobile/portable) does not hear you and will not be usable by your station until you set the tone in your radio. Any station may be set up to transmit this unique low frequency tone that allows the base station (or mobile/portable) to operate. If a base station is "In PL mode" that means it requires a CTCSS tone(PL tone) to get into that base station's receiver. Due to severe congestion of MURS activity in some areas, many base stations, mobiles and portables are PL'ed by that specific user group. So if another MURS station does not respond to your transmission to them it is most likely that they are using a PL and until you figure out just what PL they are using and program your radio to transmit that exact PL they will be unable to receive your transmissions.
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