Has DSC radio made EPIRB redundant?

Medskipper

Medskipper

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Ok if you are an ocean going yachtsman or skipper of a mobo that spends weeks or months at sea many miles from land then an EPIRB I guess should be the choice.

Having said that, most of us pleasure mobo owners only spend our weekends holidays etc around the shores of England, so has the advent of cheap DCS VHF radio made the purchase of an epirb a waste of time and money? any one out there got both? what are your views?

I was thinking of getting an EPIRB last year but now that I have a DSC radio which of course is also programmed with your MMSI number and when linked to a GPS gives out the same info as an epirb, whats the point of getting one anymore?
I am sure that the learned members will be able to inform me and others that may have been thinking of getting an EPIRB!

Many Thanks

Barry

PS. Hope this proves interesting!
 
The advent of DSC-VHF has not made the slightest difference about the relevance of an EPIRB. You are passage planning within VHF coverage from the shore stations or you are off-shore.

If you are within VHF coverage, then the use of a DSC means that perhaps the coastguard have more data more quickly, but also means that the majority of steam age VHF users are unaware of somebody neading help in their locality so a bit of swings and roundabouts within VHF coverage.

Off-shore and outside VHF coverage, having a DSC might extend the range a very small amount, but insignificant really, whereas the EPIRB works everywhere.

personally I will only change to a DSC-VHF when hell freezes over.
 
Inside VHF coverage I think my trusty old fashioned VHF will do.

Outside VHF coverage I'm inclining towards getting a phone like Thuraya which works on GSM and failing that, picks up satellite coverage. I have the phone numbers of the GMDSS rescue centres in my log book so I think that I would get a more rapid response by dialling them direct on Thuraya than by letting off an EPIRB.

Just my pennyworth.
 
Doesn't EPIRB continue to transmit and give your position form your liferaft/rib long after your boat has sunk?? So if there is any delay in a rescue response then the effects of wind and tide shouldn't be a problem..
 
I believe that they compliment each other!! It could be argued that flares are redundant due to EPIRB's but I carry all three options. Belt, Braces and Staples!!

After all I would not leave lifejacket behind 'cause I have a liferaft!!

All IMVHO

Brian
 
It all depends on where you are going.
If you want to go say from Wales to Ireland, then for at least 20 miles of that journey in the middle of the Celtic sea you will be outside of VHF range.
Ditto when crossing the English Channel, sure there are loads of ships trundling about...but would you rely on a foreign crew with a poor grasp of english to act on your PAN PAN...christ they dont even look where they are going these days, let alone listen to 16, and probably all be down in the mess room too busy watching movies to notice a DSC alert. Besides even if they did hear it they probably weighed up that it would cost the company too much to lose the allocated berthing slot in Rotterdam or wherever, to even bother thinking about stopping for you.
I mean are you really worth 300 containers full of brand spanking new multi-region DVD recorders??

I'm a firm believer in having difficult situations under your own control as far as possible, so I would opt for either an SSB radio or a SAT phone for these sorts of instances. Sat phone is probably favourite here as you can take it into the liferaft with you.
An EPIRB is, I think, the option of last resort, for those situations where events overcome you and there simply isnt time to fire off a radio call, you can then deploy it from the liferaft.

Steve
 
Vhf/DSC will only work on line of sight from mast to mast, so is fine for coastal or crossing the channel.

EPIRB. is a satellite based system, that send a signal via satellite to a land base which is then relayed to coastguard, it will work anywhere[ectp poss a cave] and give a signal that can be homed in on.
 
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Vhf/DSC will only work on line of sight from mast to mast, so is fine for coastal or crossing the channel.

[/ QUOTE ]
In theory the radio horizon at 156MHz is around 30miles which is somewhat better than line of sight. As the frequency increases then the horizon reduces.
It depends how high the communicating antennae are. On a leisure vessel not very high.
However add in the inefficiencies...untuned antenna installation, poor grounding, cable (transmission line) losses, prevailing radio conditions etc, then I think most installations will be struggling at 20 miles.
Given that the channel is about 70 miles (average) depending where you cross from then I'm not sure I would want to rely on it for the middle bit..certainly from Lands End to CI anyway.
Although I realise that thousands do, I would want all my bases covered and opt for SSB or Satphone and probably an EPIRB as well.

Steve.
 
Steve
As you know not many power boats have and SSB transmitter - the antenna length of some 23 foot put a lot of it let alone the course required to get a certificate to operate it. Never the less if the antenna problem could be overcome I would have one in the new boat.

In the meantime I want, as you say belt and braces, so I go for Sat phone, DSC VHF, Handheld VHF and EPIRB.

An EPIRB transmitting is taken seriously right away - no matter where you are.

I have observed many boats with fairly inadequate handheld VHFs as their only source of transmitting and think this is not sufficient for anything more than round the bay stuff.

So why after all the belt and braces upon which we seem to agree do you trust yourself with a non-self righting liferaft? :-)
 
[ QUOTE ]
then I think most installations will be struggling at 20 miles.

[/ QUOTE ]
Ship to ship then 20-30 miles for VHF is about right depending on size of ship and thus height of aerial. The Coastguard antenna are very much higher than that so most people should be getting abt 50 miles.

Personally in the solent I hear Portland all the time, france as soon as I come out of the lee of the Isle of White, and frequently Brixham. Probably cause my aerial is a good installation and my batteries are at full charge.
 
What if you have an incident, take on water and your electrics fail? I for one have an EPIRB and for the sake of a few quid like the peace of mind, it is nothing compared to what other non essential stuff is bought for boats /forums/images/graemlins/wink.gif
 
How many radios do you have on board? If only one then you should not totally relay on that.
What if there is a fire without a chance to send a message?

An EPIRB is a unique peace of safety equipment- there is no substitute for it.
 
That's it really then, nail on the head, it's all about installation.
To be heard at 50 miles for a 2 metre signal, will require both installations to be excellent, and probably some kind of decent gain antenna at the ground station.
It's quite common of course in amateur radio using gain (yagi) antennae, to work hundreds of miles when conditions are right but generally the equipment is much more sensitive than off the shelf marine gear, and we have the advantage of being able to use 150 watts of course rather than 25. Of course the coast stations are much higher power than 25 watts...I think most are quarter kilowatt..or used to be.
I'm not precluding working 50 miles but I wouldnt want to rely on it, and I think that although you can hear France south of the IOW, it may not be possible to reliably work it until closer in.
One of the problems on boats is the "Angle of Radiation", ie keeping as much of the signal going in a horizontal plane as possible. Although the sea is generally a very good ground plane, fibreglass boats usually dont take advantage of it, with most RF installations being very poorly grounded, if at all.
This results in very obscure radiation patterns, with a lot of signal wasted and going off up into space at a high angle.
The ideal install would be a decent 5/8 wave antenna, trimmed to band centre freq
with a good separate RF gound. The untuned 1/8 wave at the top will have the effect of flattening out the radiation pattern so that not too much escapes upward.


Steve.
 
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