Uncommanded DSC distress alert

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It may be of interest that a yacht in the West Solent early PM last Saturday succeeded in putting out a "fire and explosion" DSC MAYDAY alert without the 2 people on board being anywhere near their VHF tranceiver far less operating it. The CG asked for the make of DSC VHF and it was reported as being a relatively low cost unit which has often been discussed on these forums.

Before the introduction of DSC I knew of one specific type of VHF transceiver which could decide to make "open mike" transmission on channel 16 without any user intervention and find it very disturbing the a DSC capable unit from another manufacturer can make a DSC distress transmission without any user intervention. It makes me wonder if type approval tests on transceivers are stringent enough and are they being developed and manufactured too cheaply with adverse affect on reliability?

With many forumites seemingly regarding getting the "best deal" on equipment as being of prime importance, perhaps views on the importance of equipment quality and reliability would be of interest.
 
almost every day there's one, or more than one, vhf set on the south coast transmitting a carrier on ch 16 (eg with the transmit button pressed but no speech) which is going to cause trouble to somebody in distress one day.
 
I know everyone is being candid so they don't get sued for liable etc. But what are the makes so that we're all aware. I must admit I'd like to see the offenders of 'children let loose on the vhf' and other persons who think that all marinas operate on ch. 16 either reprimanded or fined. Otherwise the message just doesn't seem to get through that they may be putting peoples lives at risk! It just seems to be getting worse.

Never mind in two weeks I'll be setting sail from Dingle to the Azores so at least I get 2 weeks respite from the Solent radio checks and open mike broadcast of the Archers etc.
 
Wouldn't it be possible for sets to be designed so that there was a maximum transmission time after which the PTT switch would have to be released and pressed again before transmission could continue? No doubt this forum could discuss the maximum time allowed - a minute? 30 seconds?

A system like this would deal with situations where the mike was accidentally parked with the switch pressed and with those where the set itself occasionally initiates a call. My guess is that these situations, which can block ch 16 for long periods, are potentially more dangerous than most DSC problems and, as such, should be stamped on first.
 
The RYA has only last week issued a newsletter to all SRC assessors, one paragraph of which says that numerous very cheap sets are on the market and many do not carry the CE mark, which shows that they do not conform with the European spec. The RYA also advises that they are unlikely to withstand the rigours of a salt laden winter atmosphere of a British boatyard!
Additionally Mc Murdo and Simrad have ceased production of their handheld DSC radios because they are not acceptable to the European Telecommunications Union. There are probably some still on shop shelves, or could pop up at boat jumbles which are legal to use. It is the manufacture which has been banned.
Seems the EU might at last have got something right?
 
If you can't rely on the set not to transmit a DSC mayday then would you trust it to do anything else? including cutting off a transmission ...
I can see where your comming from, although I think I'd alter that to a noise suppression device - if the input noise (to the mike) is below a specific level for more than (say) 5 seconds, it cuts off, with an audible beep - or perhaps electric shock to the PTT /forums/images/graemlins/smile.gif
 
Sorry Steve but it would be illegal under ITU regulations for me to devulge specific content of a marine RT transmission, which is what I would have to do in order to state the make/type of transceiver which made the offending DSC broadcast.

However, I can advise that I know of an old Navico non DSC VHF (the one with the sloping front panel, can't remember the model number) which went on "open mike" channel 16 transmission all on its own.
 
I would be very wary of a device to cut off transmission after a set period - after all, if the "on" switch could fail, then so could the "off" resulting in an inability to raise the alert correctly cause the set keeps cutting out.

all you would be adding is yet another potential cause of failure.
 
Can you clarify the circumstance please.

My understanding from your post is that the set made a DSC broadcast from a empty yacht. Presumable the set had been left switched on even though the yacht was unattended?
 
Negative. The yacht was being sailed with 2 persons onboard, both in the cockpit with the VHF transceiver located inside the cabin but obviously switched on and unmanned.
 
Steve,

Quite agree.

I was disapointed this weekend to hear a large number of radio checks in the Harwich area, along with someone calling a Marina on 16, and several conversations taking place on 16 as well...... it seems that the Solent disease is being caught on the East coast......

As has been previously reported, the Coastguard handled the calls with grace and a polite manner, yet must be secretly fuming.......

One incident in particular, someone making a passage notification was transmitted over by a 'radio check'..... shameful stuff..... and a curt response from the coastguard.... these are the cause of the biggest risk, not rare DSC/VHF problems.....IMHO of course....
 
Two points I would like to make:

Firstly there seems to be a growing number of people calling marinas on Ch 16, more than there used to be, I wonder why?

Secondly, I cannot understand the number of people who will go out and buy 'budget' safety kit, a radio IS safety equipment. On the subject of radios, the price of some premium products is now so low, when your life may depend on it, do you realy want to save another £40 or so with a bargin basement radio?
 
Perhaps these people calling marinas on Ch16 have either not done the required VHF course and/or not checked local information on how to contact the marina. I was guilty for years of not having the relevant "qualification" but took the course earlier this year ... 1.5 days very easy and not too expensive (adult education centre!)

Budget safety kit .. well - how much do you want to spend? I can sell you a DSC VHF for £2k ... but is it any better than another? The problem with electronics is that most are ok, a few will be DOA and replaced quickly and a few will fail in situ - just when you want them - which ones are which ?? Ok, granted, there is budget and BUDGET. But there are reasonably respected makers out there whose radios I wouldn't touch with a barge pole .. and that is from personal experience rather than hearsay ....
 
[ QUOTE ]
I would be very wary of a device to cut off transmission after a set period

[/ QUOTE ]

This type of thing has been around in the Land Mobile ( land based radio, taxi, emergency services etc) market for many years, sometimes call the "time out timer",
It works very well and I am not aware of any failures in this system.

It can be set off or to any length of time required.
Most I have done or seen are set to 2 mins.
It is set up in the radio's sofware.

Whilstt it may cause an issue if you were passing a lengthy Mayday, for day to day traffic who needs to talk for more than 2 mins in each over?

Touch wood, this is the first time I have heard of this happening with a DSC set.

Regards
 
I do sail on a budget and I differentiate between safety equipment and emergency equipment. I always try not to skimp on safety equipment (my hull, sails, rigging, charts etc) and always save as much as I can on equipment which I only want to use if things go catastrophically wrong. It's part of the way that I prefer to sail.

I do have a VHF because I inherited it with the boat but don't tend to use it, and if it wasn't DSC I wouldn't upgrade it whilst people still listen on Ch 16.
 
OK, I don't dissagree with you, but, if you were to replace the radio would you go for one of the familiar branded products that are available or go for one of the real cheapies, which are not massivily cheaper than the branded product?

But think about it, halfway across the channel, you cannot change your mind. Now before the cynics kick in with the any radio can fail argument, if a manufacturer has been 'around a few years' and is willing to put a 3 year warrenty on his product and on inspection it 'looks the business', it has to be worth the extra few quid, in my mind anyway.
 
I do have a VHF because I inherited it with the boat but don't tend to use it, and if it wasn't DSC I wouldn't upgrade it whilst people still listen on Ch 16.

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Hmmm... Rupert!

I assume that it is because you "don't tend to use it" that you haven't heard the message sent out at the start of the majority of MMSI broadcasts, at least from Solent and Portland Coast Guards, recommending all pleasure boat users to install and use DSC VHF radios? It also worries me that if you don't use your VHF you are missing the most reliable source for relevant weather forecasts, strong wind warnings, gale warnings and navigation hazards. Where do you get your information from while at sea if not from CG MMSI broadcasts?
 
I don't disagree with your bargain basement comments but advise the VHF unit that made the uncommanded DSC distress call was from what I would describe as a "mid-player" in the European pleasure boat electronics field but in IMHO tries to aim the price of the VHF unit towards the budget end of the market. It is a unit which has raised much discussion on these forums due to other aspects of its operation when additional features are used.
 
A little off the subject but...
You will always get the person who will only buy a bargain basement item, as a previous post mentioned, they don't understand how easy they can get into difficulty and become another 'death at sea' statistic, was at a boat jumble at weekend and saw a stall which underlines the inablility of alot of people, who just venture to the edge of the sea, small dinghy, fishing boat etc, and would not see anything wrong with a bargain basement item....


FOR SALE - CHEAP LIFEJACKETS......
 
S'far as I know, at least until a week ago, Clyde, Belfast and Donegal, were making their usual announcements on Ch16, with vessels being directed to the local transmitter channel. For a while, last year or the year before, Belfast were fiddling about with MMSI all ships calls, but seem to have given up. Fortunately.

The noise from the alarms for MMSI forecasts are a nightmare at night - unless you use them as an alarm call for the next watch. It's a stupid and inflexible system - see endless threads about how to turn down the racket.
 
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