U could also have other units positioned in predesignated areas to relay information or set up crossband repeating.
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Looking to get ~40 mile range out of CB without 102" whip?
- Thread starter datenschwanz
- Start date
If you have not made your mind up yet this is the most viable answer of all. These services are available free of charge from Ham radio operators. They already have the equipment and the license necessary to do the job. The most it should cost you would be a bunch of coffee and some decent munchies for the guys doing the work.
When Hurricane Katrina destroyed New Orleans it was the Amateur Radio Operators that made it possible for the "First Responders" to do their jobs. Hams set up repeaters and powered them in many ingenious ways for all of the public safety services.
Lol 4w fm yeah ok..... with a strate line
And you have no clue on the land scape so how can you even take a shot at me like that...???
Why don't you enlighten us On your antenna install. insted of just stating i dont know how to install a antenna..
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I never used GMRS but I was refering to the nicer ones made by Icom, Yaesu, and Motorola, not those cheap ones for sale on Amazon for $20.00.
Advertising claims are subjective and usually published when, or if any test were done under the best conditions to give the best results.
The name brands mentioned are the maximum wattage allowed for this radio service and manufacture claims are for 25 miles or more. With a disclaimer of course to obvious terrain and surroundings.
I only made the suggestion because I do know and have talked to hams using a repeater tower which are usually ideally located can be hit with a 5 watt handheld 2 meter from up to 50 miles away and hit the machine quite well. Not bad for 5 watts.
So based off that I made an assumtion that 4 watts on GMRS could probably make around half the distance between multiple radios as long as there out in the open.
As for communications between big hills, big rocks and mountains,
Even repeaters, cell phones, and BIG RADIOS are not reliable for constant communication.
Have you or anyone else really used a GMRS radio and give a honest report on the range of these for both wide open area and hilly terrain?
I'm curious for myself and it might still be helpful for the original poster and others reading.
Thanks.[/QUOTE]
Sorry not making fun.. more making fun of the package that tells people you get 30+ miles
I was useing a par of Motorola pr400s 4 watts on gmrs and after a mile or 2 in the woods it was no good..
No offense taken, just was wondering about these because I was asked by a co-worker if these really had the range advertised because he was looking into these types of radios to use with his hunting party.
Thanks for answering about these because I had my doubts about them since they seem to be a glorified walkie -talkie.
Take a drill. Do the one thing that the vast majority of people refuse to do and drill a big hole in the centre of the roof of the vehicle. Install a fixed antenna mount in that hole. On that fixed mount attach the largest antenna you can find, preferably something like a Sirio Hypower 4000/Performer 5000 or something of a similar or longer length. Next bond the trunk, the doors, the hood to the main body of the vehicle.
Et-voila. An installation which will go further with 4W than you will do with 100W into a 4ft firestik shoved on a magmount on the back of the cab or the mirror arms of your 18 wheeler or a whip mounted to the bumpers of your truck.
The range claims made by the makers is B.S. I have two gmrs/frs that were a total waste of money. The range claims are measured on an antenna range in the middle of a desert away from all of the electrical noise of civilization. The Wife and I were in two separate vehicles and even though we could see each other that radios could not make contact. There are repeaters for GMRS around but they are usually around lakes or state parks.
FRS and GMRS are not in my opinion suitable for critical communications in which a life or death situation might occur. The cell phone would be better.
With the exception of CB radio, a limited amount of power on MURS or FRS, you cannot operate anywhere else without getting some type of license.
A Ham license you have to earn by taking a test, while GMRS you just buy - each person @ $85 for 5 years.
Its not the amount of power that determines how far of a distance a transceiver will communicate with another transceiver, but the location of the antenna's.
Even with a legal CB radio, if you could put two operators on mountaintops, you could relay your messages through the mountaintop repeater people.
20 miles is not an unreasonable distance. Hence two operators at either end 20 miles apart, or multiple operators on mountaintops should be able to relay your messages.
It isn't the amount of power radiated, it is how you radiate it.
We have this all the time on 75m phone. One operator doesn't have a good antenna and so he uses an amplifier so everyone can hear him, the couple of extra Db he gains is insignificant unless everyone else uses amplifiers so he can hear them.
A good antenna makes much more sense then trying to use 600 - 1000 watts to do the same thing.
NOT GROUP - FAMILY..
Mom, dad, brother, sis, aunt, uncle, gramps, grandma - maybe even a cousin.
You keep using the term RADIO.
To me - a radio is a one way device.
What you want to say is handheld or transceiver...
A GMRS transceiver will not talk 40 miles, the frequency is too high and the loss too great for a 40 watt mobile and a 5/8ths wave antenna to talk that far without the assistance of a good repeater... GMRS repeaters are generally closed repeaters, not like amateur radio - where the county / government usually builds one or two repeaters for the local hams to use.
A GMRS handheld will only have a range of LOS - Line Of Sight..
I've used them in the woods in the winter in places where a GMRS 1 watt radio wouldn't talk 400 yards, while in other places, talking to a 40 watt base station with a good antenna atop a 40' tower, we got as much as 3 miles range out of them.
Its the antenna's job to do the heavy lifting, a mag mount antenna cannot capacitively couple well enough to the body of the vehicle at frequencies near 11 meters.
What a joke, a 400 watt amplifier will not increase a mobiles range enough to talk 40 miles. First you need to deploy a better antenna - such as a IMAX 2000 and then you need to get it up as high as you can get it - 40' would be a good starting place and then you would need to use some good quality low loss coax.
Setting up a ground plane beneath the antenna would be a good start.
Why do you say GMRS is only good for 1 mile?
GMRS - is a licensed radio service. You can use a transmitter with 40 watts if you have a license and there is some repeaters still out there. Technically there is no difference between the GMRS frequencies and the amateur radio 70cm service, which amateurs use on a secondary basis.
I have talked from USA to mobiles in England that were in a mobile and only running 25 watts into a shortened 102 inch whip while I only had 100 watts SSB into the old Solorcon A99..
You just have to differentiate between groundwave and skywave.
I have talked to mobiles in Flordia - 500 miles away on 10 meters, and the mobile was only using a K40 antenna and 25 watts. The amount of power you radiate is not as important as the band conditions and the antennas used.
NOO - a desert is the wrong place to check the range of two transceivers because of the soil conductivity. And, electrical power line noise should be just 60 cycles, while ignition noise is almost non existent - especially on GMRS frequencies. We still have some noise from plasma televisions and fluorescent light bulb ballasts etc...
If you are in a vehicle, the body and glass of the vehicle acts like a Faraday Cage.
Your range is dependant upon the height of both antenna's and the topography - what is between those antenna's.
The flattest reflective surface you will find is probably a lake.
Of all of the great lakes, Lake Erie has the smallest waves.
So if you wanted to make a range assessment, you would find the two largest ships that sails on Lake Erie and you would go to the highest point on the ship and communicate. The metal surface of the ship would act as the ground plane.
Path loss is insignificant - you can talk to a satellite or the International Space Station with just a cross polarized antenna and a 5 watt handheld radio, and the ISS is 205 - 270 miles above the earth at any one time.
The ground plane for 10/11 meters is about 9 feet square.
The only vehicles with that kind of steel would be a Chevrolet Suburban or a Ford Expedition. It takes multiple bonding - because of all of the plastic.. RF likes lot's of metal. So you would have copper braid, at least 1 inch wide, 2 places on the hood to cowl, the fenders to the body, the doors to the body, 4 places the body to the frame, 2 place the engine to the frame, 2 places the rear axle to the frame, the exhaust to the frame, the rad core support to the frame, everything metallic bonded together.
We did a bunch of tests years ago and found that nothing beat a 106 inch whip with stainless spring, as long as you didn't have any issues with the connector inside of the spring. Just because it is a stainless steel spring doesn't automatically mean that the copper strip inside of the spring is not damaged. I have seen issues where the antenna was tuned while the vehicle was stationary and then when the whip started bouncing around, the antenna make and broke contact and wouldn't work right. And it was because the connector inside of the spring was no good.
Anything other then a quarter wave whip is a compromise antenna.
The quarter wave whip uses the vehicle body as the missing half of the dipole antenna.
I never advocate an amp over a good antenna but someone needs to flaunt their knowledge.
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