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At the chain marine store recently I asked the clerk a question about the handheld vhf radios. He went on to confuse me about range and line of sight saying something along the lines of if you were out a few miles offshore they wont work? Can anyone weigh in on this?
 

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Short version, is that yes, as you get farther, they won't be able to reach to communicate with shore units, etc. It isn't that they aren't working, obviously, just that the range will get a limit, usually a few miles, depending on transmit power. I think Handhelds go up to usually a max of 5 watts, whereas fixed will run up to 25 watts. Another thing to consider, is the antenna. If you were to hook a mast mounted antenna to a handheld, you would likely increase your range a bit over using the little stubby one on the unit (assuming one that is able to do so). It's not to say that the handhelds are worthless, they are very handy to have especially in an emergency, as if you have to abandon ship, you can't very easily take a fixed VHF and battery with you. Just that compared to a VHF, they have a smaller range due to the lower power, and antenna usage.
 

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I think that a 5w handheld standing near the waterline gets you 5-8 miles in good conditions. I understand a 25w with an antenna at the top of a 60' mast to be 15-30 miles.
 

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line of sight, and 12-20 miles on transmit....you can almost always "hear" more distant stations, but they would not be able to hear you

It is all about power, antenna gain and height of that antenna....at the VHF frequency the handheld uses.
 

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Here is a useful VHF/UHF line-of-sight calculator. It does not take into account power, the height of the other antenna or any other variables. It just provides the distance to the horizon at a given height above the water.

Radio Line of Sight Calculator for use on VHF/UHF Ham Bands

I would guess that standing in my cockpit with a handheld I am about 9 feet up. The calculator shows 3.7 miles. If I am communicating with a similar station the maximum (theoretical!) distance we could be from each other is twice that or 7.4 miles.

Once I fish a new cable through my mast I can put an antenna back up at about 30 feet. This increases the range to 6.7 miles.

Basically you have to be able to "See" the other station. VHF and UHF will not go through the earth and in most conditions they will not "bounce" off the atmosphere like radio waves in the HF band (SSB Marine, for example).

73 de AC0ZA
 

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I think that a 5w handheld standing near the waterline gets you 5-8 miles in good conditions. I understand a 25w with an antenna at the top of a 60' mast to be 15-30 miles.
It does depend on who you are communicating with. If its the CG on Ch 16, they have a tower.

Also some of the hand helds will go to 6 watts not that the difference between 5 and 6 is worth anything. I have two: an old hand held, and a new fixed that connects to my GPS for an accurate DSC MayDay longitude/latitude location. My mast height is only 22 feet.
 

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In reality, power has very little to do with VHF communications systems. Keep in mind that signals transmitted from satellites are usually less than 1 watt of power, but the line of sight is incredible. I worked with lower power VHF transmitters many years ago while working for Vitro Laboratories in Silver Spring, Maryland. We worked on a project that was the precursor to the Hubble Telescope, we sent a replica to 80,000 feet, suspended from the bottom of a massive, helium filled balloon. The transmitter for the instrument package was just 1-watt and we received the data transmitted from distances to 300 miles with incredible clarity.

Now, think about your cellular telephone, another tiny transceiver that works on VHF frequencies. If it were not for the elevation of the tower antennas, it would be nearly worthless as a communications device. Output power is usually less than 1/10 of a watt.

The output power of my Spot is just a few milliwatts, yet, it fires a signal from my boat up to an orbiting satellite that is then fired back down to a ground station and sent out via the internet to email recipients. Forget power - it has little to no bearing on VHF communications.

When you're standing on the deck of a boat with your handheld VHF transceiver, 6 miles is where the horizon is, so that's about the best you can expect, even on the 5 watt setting. Take that same handheld up the mast in a bosun chair and you will find a huge difference in range.

Cheers,

Gary :cool:
 

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Water Lover
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The most common situation that comes to mind is smaller vessels where both operators are working at a height of 5 to 8 feet or so.

Two special situations:
* person in water with (immersible) handheld -- even more poor transmission.
* talking to the Coast Guard, which may have towers 100 feet or more high, on top of mountains or cliffs, etc. -- of course, can be fairly long range reception.
 

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A hand held VHF will give you about one mile.

Zanshin is correct that its further if a Coast Guard tower is close by.

But in real life sailing situations hand held VHFs are as useless as tits on a bull.

Fine in an anchorage to swap recipes, or talk to dudes controlling a bridge, or putting in your belt to look cool at a bar... But dont expect anyone to hear you.


Mark
 

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A handheld is good to have so you can be in contact with the nearby rescue boat or helo, after you've lost your mounted unit or house batteries. Actual comm distance is very limited. 1 mile is about all I would count on. 3 would be pretty lucky, if there is any background noise, waves, etc.

I think, however, that a DSC feature will transmit further than the voice. But don't trust your life on that assumption.
 

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BJV
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Disagree, very handy to have a handheld.
-Great in florida for the bridges, can keep main on 16 and hand held on 9
-Great for dingy. Cruising islands many times long way from help, hand held great if something goes wrong while exploring.
-If one of us ashore will carry handheld to communicate with mother ship.
Just have to understand the limitations of range, be we typically get 1-2 miles in all conditions. Cant shout that far.

A hand held VHF will give you about one mile.

Zanshin is correct that its further if a Coast Guard tower is close by.

But in real life sailing situations hand held VHFs are as useless as tits on a bull.

Fine in an anchorage to swap recipes, or talk to dudes controlling a bridge, or putting in your belt to look cool at a bar... But dont expect anyone to hear you.

Mark
 

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Disagree, very handy to have a handheld.
-Great in florida for the bridges, can keep main on 16 and hand held on 9
-Great for dingy. Cruising islands many times long way from help, hand held great if something goes wrong while exploring.
-If one of us ashore will carry handheld to communicate with mother ship.
Just have to understand the limitations of range, be we typically get 1-2 miles in all conditions. Cant shout that far.
I agree with the disagreement!:)

I have a fixed VHF, with DSC, at the nav station, antenna at the top of the mast (~50ft) and a 6 watt floating handheld (without DSC) that I keep in the cockpit anytime that I am underway. 95% of the time I use the handheld to communicate with marinas and other vessels, at a surprising range (guess is ~2nm). Anytime that the dinghy is away from the mother ship, the handheld is along for the ride.

A handheld VHF is MUCH more useful than the mammary ducts on a brass Bos Taurus..
 

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...
-If one of us ashore will carry handheld to communicate with mother ship.
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Unless you have an FRS frequency or have a license, it's my understanding that marine radios cannot be used on land.

http://wireless.fcc.gov/services/index.htm?job=operations&id=ship_stations

You must have a special license, called a marine utility station license, to operate a hand-held marine radio from land -- a ship station license IS NOT sufficient. You may apply for this license by filing FCC Forms 159 and 605 with the FCC. To be eligible for a marine utility station license, you must generally provide some sort of service to ships or have control over a bridge or waterway. Additionally, you must show a need to communicate using hand-held portable equipment from both a ship and from coast locations. Each unit must be capable of operation while being hand-carried by an individual. The station operates under the rules applicable to ship stations when the unit is aboard a ship, and under the rules applicable to private coast stations when the unit is on land.
 

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Until relatively recent years, all transceivers were required to be licensed. When I got my first big boat, at age 22, I had to apply to the FCC for my VHF license. Back then, we also had an active radio/telephone system by utilizing channels 24 through 27 (I could be wrong about the channel numbers) and there was no charge for local telephone calls over the VHF.

I don't believe their is a restriction to usage on land or water. Keep in mind that many of the communications and emergency centers are land based and use VHF communications. Same is true for marinas, inland lake resorts, USCG, aircraft, etc...

Though I have not checked, I believe the radio/telephone channels no longer exist, at least in the United States.

Cheers,

Gary :cool:
 

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I don't believe their is a restriction to usage on land or water. Keep in mind that many of the communications and emergency centers are land based and use VHF communications. Same is true for marinas, inland lake resorts, USCG, aircraft, etc...
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I don't know, Gary. All I know is what the FCC says as I posted.

Marinas, restaurants, etc. have a special license to be able to converse with boaters on VHF.
 

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A handheld is good to have so you can be in contact with the nearby rescue boat or helo, after you've lost your mounted unit or house batteries. Actual comm distance is very limited. 1 mile is about all I would count on. 3 would be pretty lucky, if there is any background noise, waves, etc.

I think, however, that a DSC feature will transmit further than the voice. But don't trust your life on that assumption.
The handheld is a back only AFAIC. And its great for listening to the weather while sitting out next to the tiller.

But I had someone else on another thread tell me that MOB was a May Day situation, like that would solve everything. Heck, MAYDAY in my opinion only means that you are desperate and scared [email protected] Just because you blast out a Mayday doesn't mean anyone is coming soon. Where I sail, it will take to CG at least 25 minutes to get there, and any of the harbor masters about 20 minutes.

I need to have backups for almost any situation on the boat and not rely on a Mayday. And often, I could be solving the problem rather than wasting my time on a MayDay.

Everyone should have a procedure and a back up for every situation, IMO, especially if you never think it will happen.
 

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The range of any handheld radio will be limited pretty much by three things:
1-Output power. (Almost all marine VHF handhelds are 5 or 6 watts, about the same.)
2-Background noise. These are FM radios, the one strongest single captures the channel on the receiver, and that's the only signal that gets through.
3-Antenna height. These are all "line of sight" communication for technical reasons. SO unless your antenna can see the other antenna, and vice versa, you generally can't communicate. (Sometimes you can under some changing and unreliable conditions, I'm ignoring that here.)

If your handheld is about 6-8 feet above sea level, and you're trying to reach a USCG shore station that may have their antenna 50-100' up in the air, your range is based on the ~7' height to the ~75' height and that's going to work--if there's no background noise and competition-- over a much greater distance than two handhelds, each in boats.

Some radios are poorly tuned out of the factory, and don't put out their full rated power. Or, someone is using flat batteries and not getting full power. But generally a handheld is an integrated system, and I've seen them outperform full-power installed radios which were being crippled by the often degraded and corroded antenna being ignored up the mast. If a handheld isn't working, it is easy to send in for repairs. If a ship's radio isn't working...someone has to go aloft to start checking things. So their advantage isn't always there.

Either way--but a quality brand, the cheapest ones tend to fail sooner rather than later. They may look alike, but they're not built as well.
 
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