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Discussion Starter #1
Most of the GMRS FRS radios I'm seeing with claims of 36 miles seem to be unrealistic based in the real world experiences of reviewers. I'm willing to plunk down real money for radios that will actually live up to the advertised range. Ideally, I want at least two radios that will tx/rx reliably a minimum of two miles. Of course more than two miles would be better but I think that is the limit of line of sight.

I believe I can get that range with the cheap Baofeng ham radios but two things are keeping me from buying them. First, they are Chinese and as such the reviews say they are junk. They work great until they get broken. Secondly, I don't have a HAM license and dont have immediate plans on getting one.

Basically, all I need, is a semi-rugged radio that will actually transmit two or more miles reliably in an emergency situation. Any recommendations will be appreciated.
 
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Discussion Starter #3

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Radios ranges are always listed as a best case scenario (no obstructions, clear line of sight, holding your mouth right, etc). Handheld to handheld, power and antennae length will be your friend so long as the actual radio design is good. Three are 5 watt handhelds out there, but I can't give you any recommendations.
 

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Antenna is more important than transmit power. With recent changes in the FCC regulations radios which transmit on the GMRS frequencies which do not exceed 2 watts peak transmitter output, and which do not operate on the split-frequency pairs used for repeaters, do not require a license. Using a half-wave mobile antenna, which gives you a clear RF path outside the metal vehicle, and unity gain, you could expect 2-3 miles on direct simplex if not adversely affected by ground clutter or terrain.

Realistic expectations for two vehicles each equipped with a 2-watt UHF radio and unity gain mobile antenna similar to http://www.dpdproductions.com/page_gmrs.html mounted high on the vehicle roof:

Mountain to Valley: Line of Sight Up to 35 miles

Open Water: Up to 6 Miles

Flat terrain, Interstate Highway with minimal vegetation or ground clutter: Up to 3 miles

Suburban Neighborhood: Up to 2 Miles

Dense Urban High Rise Development with steel reinforced concrete buildings: Up to 10 city blocks, or 12 vertical floors

For more info see:

https://apps.fcc.gov/edocs_public/attachmatch/DOC-344617A1.pdf

https://apps.fcc.gov/edocs_public/attachmatch/DOC-344944A1.pdf

https://forums.radioreference.com/gmrs-frs/352394-part-95-rule-changes-finally.html

FCC Updates Personal Radio Service Rules | In Compliance Magazine
 

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Marine bands.
G. Portable Marine VHF Radios on Shore.
Section 80.115(a)(2) of the Commission’s Rules prohibits the use on shore of a portable marine VHF radio associated with a vessel. The GMDSS Task Force proposed that the rule be amended to allow persons on shore within three miles of the water to use portable marine VHF radios to communicate with the vessel that is subject to the ship station authorization. The Commission, however, noted that limitations on the use of maritime frequencies are intended to minimize interference to maritime communications (particularly distress and safety messages), and tentatively concluded that permitting the use of portable marine VHF radio transmitters on shore would not further the public interest.

We questioned the practical enforceability of a three-mile rule, and asked whether shore parties’ communications needs could be met by commercial mobile radio service (CMRS) or PRS options. The Commission also asked commenters supporting the proposal to discuss what limitations would be appropriate to minimize the impact on maritime communications. The GMDSS Task Force acknowledges that CMRS options likely will be preferred in areas with reliable coverage, and asserts that this makes it unlikely that use of low-powered portable marine VHF radio radios on land will interfere with maritime communications. It also argues that permitting such use will further the public interest by encouraging more boaters to a carry a VHF radio, which has safety benefits not available from CMRS or PRS options because marine VHF channels can be used to contact the Coast Guard and other nearby vessels in a distress situation, for bridge-to-bridge communications, and to receive maritime safety information broadcasts.

We agree with commenters that the public interest will be served by allowing the use of portable VHF radios ashore, so long as it is limited to enhancing the usefulness of marine VHF radios without negatively affecting maritime communications. Such limited onshore use will promote flexibility in the use of marine radio equipment in a manner that furthers maritime safety by encouraging more boaters to a carry a VHF radio. Specifically, as suggested by ACR, we will permit use of portable marine VHF radios only in areas adjacent to the water, such as docks and beaches. In addition, as suggested by RTCM, and consistent with our requirements for offshore use, onshore communications using such radios must relate to the operational and business needs of the associated vessel, and must be limited to the minimum practicable transmission time. We amend Section 80.115 accordingly. We caution operators that the Commission’s Enforcement Bureau will continue to investigate complaints against operators who improperly use marine VHF radios, particularly any violation that concerns unauthorized transmissions on 156.800 MHz (VHF Channel 16).

https://apps.fcc.gov/edocs_public/attachmatch/FCC-16-119A1.pdf


 
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I've got a galaxy dx 44hp radio that's been tuned to the cb bands an it gets out very well.. I use it with a whip style antenna on my pick up. I understood you were talking mobile units. 2 mile range on this radio is easily achieved.
 
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Ditto Outpost.

Range of reliable communications will depend upon what's between you and the the other radio. Outpost's range estimates are r alistic for 2watts output.

Communication reliability is compromised by the design of the radio, especially the antenna (very short stub), as well as local terrain, intervening structures, trees, and local weather. If you're in a gully, or a forest, you'll have trouble communicating even 1-2 miles. If you're on a mountaintop you'll have no trouble reaching the outskirts of the town you can see 15 miles away.

It's not the power limitation of 2 watts, as much as the small antennas on th two radios. I can talk around the world with 4 watts, but only under optimum conditions. I can't do it every day, nor can I choose where I'll be heard, but if the conditions are right, it can be done.

The GMRS radios are not as reliable as cell phones, but neither are they intended to be. They may or may not be able to get through during an emergency.

On on the other hand, if you decide to try a pair of GMRS radios, you don't need to spend a lot, nor buy the most expensive one with the most features. Any radio that puts out the permitted 2 watts will potentially work just as well as another. You should be above to find a pair for $20-40. Try it out where you intend to use it. You won't be out much and it may do what you want it to do.
 
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Discussion Starter #10
I think I'm going to look into additional radio and antenna options for GMRS. Both mobile and handheld. Also looking into 5W walkies too. I'm envisioning the radios being used primarily as walkies and not thinking outside the box. On foot with a backpack, I'm thinking that a handheld radio can be stowed in a holder attached to the backpack, an external mic on the shoulder or headset and maybe even figuring out some way to incorporate a better antenna into the backpack itself. Think ww2 backpack radio with long honking antenna, same principle idea but much much more compact.

I realize 2 miles is the LOS limit for handhelds, even for ham radio without a repeater. I just want to get an actual 2 miles, no matter where, no matter what.
 

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Using hand held you can do very well with Larson or Centurion telescoping half-have antenna, with radio held vertically at face level, not using a hand mic with the radio in your belt. Makes BIG difference! Full-sized quarter-wave whip with a counterpoise wire attached to shield of connector almost as good. Flexible helical antenna which comes with the portable is a VERY poor radiator, typically NEGATIVE 5db gain compared to an isotropic source. With a 2watt radio and unity gain antenna, such as 1/4 wave with a ground plane or counterpoise, or half-wave without a ground plane, two miles is reality in open, level terrain. Using the helical "rubber duckie" that comes with the radio effective radiated power is only about 400 milliwatts and range about 1/2 mile at best.

Antenna isn't everything, it is the ONLY thing which matters.

When we ran comms for SAR the COML carried an 8db, 3-element yagi antenna on a full wavelength 70cm boom, on a telescoping pole to that it could be elevated and aimed directly at portable repeater placed at ridgeline on forest service access road. We could maintain contact with the VAEOC in Richmond, 100 miles away by using the 2w handheld with portable yagi to hit repeater on Reddish Knob 20 miles away. We could also maintain simplex contacts without using the repeater, for 5 miles aiming the yagi at the locations we wanted to reach.
 
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I think I'm going to look into additional radio and antenna options for GMRS.....On foot with a backpack, I'm thinking that a handheld radio can be stowed in a holder attached to the backpack, an external mic on the shoulder or headset and maybe even figuring out some way to incorporate a better antenna into the backpack itself. Think ww2 backpack radio with long honking antenna, same principle ideaI just want to get an actual 2 miles, no matter where, no matter what.
What we did with SAR radios is mount handheld up high on telescoping mast attached to pack frame, so radio is about head level, and use 1/4 solid whip on the portable with 1/4 wave counterpoise wire attached to shield of antenna connector at radio chassis and dangling, tied off to pack.

Then use hand mic plugged into radio. Power radio from 7ah gel cell battery in backpack. We were using VHF high band 155.16, 155.175 and 154.28, but principles are the sale.
 
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