What is the range of hand-held (5W) vhf radio at sea level ?

SHUG

SHUG

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Many owners of small craft carry a hand-held VHF radio on board, primarily for emergency use. With the loss of many local Coastguard stations we now depend on VHF relay stations to transfer the call to the nearest main coastguard station.
My nearest relay station is about 8miles away and when I called the Coastguards for a radio check on my hand-held (Icom) at 5watt power with a fully charged battery, I was told that the signal was "very weak".
A better and cheaper option might be to put a mobile phone in a waterproof pack and dial 999 if an emergency occurred. I think that in some coastal areas the mobile phone coverage is possibly better than the VHF coverage.
What does the Forum think?
 
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VHF range is a function of height of Tx aerial and Rx aerial above sea level as the radio waves travel (roughly) in straight lines. Some propagation conditions can extend or diminish the theoretical distance.

Mobile phone signals rely on a land-based station, and again, with line of sight being the key condition.

VHF can be relayed from one boat to another to Coastguard, when mobile relay would be impossible. Triangulation of a VHF Tx station position is relatively easy, but geolocating a mobile signals is a lot more difficult and requires extra work from the service provider - you will be in a circle of only one cell holding the link to your mobile, and that cell could be 100 miles sq.

Improving a h/h VHF signal is possible with a drop-in emergency aerial being held e.g. on top of the cabin, or connecting it to a ready rigged emergency aerial on a gantry. Extending aerials for mobiles are very rare; they used to be set up for cars, but not now.

The first course on a boat is to use VHF, with mobile having uses such as speaking with e.g. the Coastguard Association stations a s you pass by, or calling a marina re berthing. The emergency services and others can listen in to a VHF; a mobile is to one other phone only.

I cannot see a mobile phone being a priority over a good VHF. Supplementary sometimes, yes.
 
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I would not bet on more than four or five miles under normal conditions. Atmospheric conditions can greatly increase this and I have talked to stations more than a thousand miles away with 5w from a hand-held transceiver (admittedly using SSB rather than FM) - but that sort of thing is extremely rare.

Mobile phones can do better - it is not uncommon for a British phone to get a lock onto the UK network from Calais - but I would not rely on it to the exclusion of carrying a VHF handie.
 
I would describe the range of a HH VHF as 'variable'.
Plenty of places close in where you are not going to get a signal.

Likewise you may not get a phone signal everywhere.
The big advantage of VHF is that other boats are likely to hear you.

A phone in a waterproof bag is a very sensible thing to carry as well as a VHF.
If I got no response on the VHF and my phone had a signal, of course I'd use it.
 
Also don't forget that a VHF should be held so that the antenna is vertical and not like a phone which invariably held at an angle.
 
Quite apart from line of sight of issues, it depends on the gain of the receiving antenna. A good receiver will pick up your signal a lot further away than another handheld. How far you can be heard shouting depends on your voice and the other person's hearing.
 
Thanks JimC.
The earlier thread you quoted from. from (2015) contains most of the information I was looking for.
The conclusion seems to be that the VHF coverage for hand held VHF is so patchy that a mobile phone for back- up is essential.
There are now many waterproof phones available including Samsung Galaxy S8. HTC U11. 2LG G6. Apple iPhone 7. Sony Xperia XZ Premium. Samsung Galaxy S7. Samsung Galaxy S8 Plus. 9Nomu S30. Unfortunately they are all more expensive than a hand-held VHF
 
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I was unable to get a reply from the coast guards when crossing St Andrews Bay. initially tried the HH then the ship radio but got nothing. I don't know how they expect to cover this. On the approaches to Aberdeen we did manage to raise the harbour authorities, but couldn't even receive the routine weather reports. I didn't realise how spoilt we were on the South Coast.
 
sarabande said:
I cannot see a mobile phone being a priority over a good VHF. Supplementary sometimes, yes.
Click to expand...

Depends on your location. In much of the Caribbean there is no dedicated band of coasties monitoring ch 16 day and night other than the French islands. I have the police and some other numbers on speed dial for each island. In the event of someone needing urgent assistance a phone call to the right person will often work. Calling on 16 or 68 [ our local hailing channel ]might raise another cruiser who has the right numbers on his or her speed dial.
 
SHUG said:
Thanks JimC.
The earlier thread you quoted from. from (2015) contains most of the information I was looking for.
The conclusion seems to be that the VHF coverage for hand held VHF is so patchy that a mobile phone for back- up is essential.
There are now many waterproof phones available including Samsung Galaxy S8. HTC U11. 2LG G6. Apple iPhone 7. Sony Xperia XZ Premium. Samsung Galaxy S7. Samsung Galaxy S8 Plus. 9Nomu S30. Unfortunately they are all more expensive than a hand-held VHF
Click to expand...

A £20 PAYG in a £10 waterproof bag is a better answer IMHO. For one thing it floats. Also the cheapies often have amazing battery life.
Depending on where you intend to sail, it might be worth being on a different network with the PAYG phone. There are still beaches in Devon with no Vodafone coverage, and coming back across channel, it's a lottery who gets a signal first.

Where I am, at the top of the harbour I would be lucky to get heard on VHF. And I suspect things are more likely to go pear-shaped up there than out at sea. I wouldn't want to call mayday for e.g. a broken shear pin on the tender outboard, but I might phone a friend....
Other times I use my HH VHF a fair amount.
 
SHUG said:
Thanks JimC.
The earlier thread you quoted from. from (2015) contains most of the information I was looking for.
The conclusion seems to be that the VHF coverage for hand held VHF is so patchy that a mobile phone for back- up is essential.
There are now many waterproof phones available including Samsung Galaxy S8. HTC U11. 2LG G6. Apple iPhone 7. Sony Xperia XZ Premium. Samsung Galaxy S7. Samsung Galaxy S8 Plus. 9Nomu S30. Unfortunately they are all more expensive than a hand-held VHF
Click to expand...

I use a Swimcell waterproof pouch, it works OK, the touch screen works normally through the cover
www.swimcell.com

Alternatively Mr Banggood offers a range of waterproof mobiles
https://www.banggood.com/Wholesale-Waterproof-Phones-c-4542.html
 
When you charter in the BVI they give you a mobile phone and tell you to use that in an emergency, explaining that the terrain means that VHF has no useful range
 
Muddy32 said:
Try running racing and try to talk to the RIB with a handheld more than a mile away- he may hear you but the reverse is a no no.
Click to expand...

I was doing more or less exactly the reverse of that last week. Committee boat to hand held on shore, worked OK both ways with us about two miles out, provided the bloke on shore was not indoors or something similar. Shore h/h to h/h in the RIB was more hit and miss.
 
SHUG said:
Thanks JimC.
The earlier thread you quoted from. from (2015) contains most of the information I was looking for.
The conclusion seems to be that the VHF coverage for hand held VHF is so patchy that a mobile phone for back- up is essential.
There are now many waterproof phones available including Samsung Galaxy S8. HTC U11. 2LG G6. Apple iPhone 7. Sony Xperia XZ Premium. Samsung Galaxy S7. Samsung Galaxy S8 Plus. 9Nomu S30. Unfortunately they are all more expensive than a hand-held VHF
Click to expand...

From personal experience I know now that the Samsung S7 Edge (maybe others too) is only waterproof in fresh water. Following a short exposure to salt water mine no longer charges via cable (although wireless charging still works). To be fair since paying a bit more attention I have noticed the fresh water only disclaimer on their advertising/instructions. Apart from the charging it is fine following its dip.
 
SHUG said:
Many owners of small craft carry a hand-held VHF radio on board, primarily for emergency use. With the loss of many local Coastguard stations we now depend on VHF relay stations to transfer the call to the nearest main coastguard station.
Click to expand...
It has always been so.
SHUG said:
My nearest relay station is about 8miles away and when I called the Coastguards for a radio check on my hand-held (Icom) at 5watt power with a fully charged battery, I was told that the signal was "very weak".
Click to expand...
I work on the principal that there are other people on the water with their radios switched on that will respond and perform a Mayday Relay should I need to use the handheld to call for help.
SHUG said:
A better and cheaper option might be to put a mobile phone in a waterproof pack and dial 999 if an emergency occurred. I think that in some coastal areas the mobile phone coverage is possibly better than the VHF coverage.
What does the Forum think?
Click to expand...
One option, but I've had a phone screen crack and drowned two phones even though they were in waterproof bags - it really takes a tiny amount of water to FUBAR a phone. I now have a IP68 rated BV6000 phone that, so far, has been OK
 
When my boat hit the rocks at the base of Boulby cliffs, I expected there'd be little chance of raising assistance with the handlheld. But (very!) fortunately my Mayday was received by an unseen drilling rig, several miles offshore. Initially I was broadcasting on the fixed set, but when there was no response I tried the handheld, and got through on that. I have no idea whether the fixed set was working or not, at that time.

ps I know for a fact my phone would have been no use at all. The cliffs were blocking the signal right along the surrounding coast.
 
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Aren't the relays in similar locations as radio reception has always been? Just because the person is not in the same location does not make it worse. HH audio can often be difficult and you se a lot of operators not actually speaking into the mic or shouting and overloading the audio input.
 
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