DSC, its time to make the MCA listen

[Sans Bateau]

Some of you will, I am sure, have read my post on the Scuttlebutt forum (about to go off the page) titled "So whats the matter with DSC?" You may also have read the post on the PBO forum by 'bendyone', again the subject being DSC.

I will not discuss the subject matter here, but the PBO post was concluded with the opinion, driven by Jon Brookes of ICOM, that the only way we stand any chance of DSC becoming a usable safety device ie people not turning their sets off to stop the rubbish, is for us to all write to the MCA.

According to Jon Brooks, there are 66,000 registered marine VHF users in the UK and that a recent survey showed that 12% are disappointed with DSC, for the same reasons as demonstrated in these threads. If we can arrange for nearly 8,000 letters to land on the desk of Mike Martin, or as Jon suggested Martin Hart at the MCA, then we may get somewhere. If all that effort then fails, turn the radio off.

Personally I will print off the threads and send a copy to the MCA, so that they can see the issue is very much on our agenda

 

[Stingo]

Okay, what date do we all post our letters and what is the address?

 

[Koeketiene]

IMHO DSC should have the same option NAVTEX has. Let me try and make myself clear.
All NAVTEX messages are "coded" according to their subject. Like icewarnings, navwarnings, weather, admin msgs,... you name it. WhenI first got my NAVTEX I left it on overnight. In the morning there were 40-odd msgs, hardly any of interest to me. Read the manual - a first! - and found I could set the set to only receive the signals I was interested in (in my case weather). Next morning 6 msgs. Result!

You should be able to set your DSC to only alarm in case of a genuine MAYDAY or a direct DSC call to your station. I'm sure it's technically feasable.

William

 

[Oldhand]

I think you are making an excessive fuss about DSC alarms. Isn't it more of a case that many installations make DSC alarms a pain to read and/or cancel? Why not do something to make the installation work more conveniently? /forums/images/graemlins/tongue.gif

 

[tome]

Oldhand

It's the equipment standards which I believe to be the root cause of the problems. Pre-DSC we could turn down our volume controls to a level where the on-deck watch would still hear a Mayday, but the off-watch were not disturbed below.

Now, the DSC set over-rides the volume control with a piercing alarm at full blast which is enough to put the fear of God up the deck watch, and seriously disrupt the watch below. If this only happened with distress calls I think I could just about live with it. However, in some areas it goes off every 15-20 minutes for routine safety traffic. On a crossing of Lyme Bay it became impossible to sleep below with full blast alarms going off every 15 minutes to warn us (yet again) of firing range info. This was from a RN vessel.

My own belief is that the alarm should be linked to the volume control and not bypass it. In the Lyme Bay crossing, we switched off the DSC set and reverted to a non-DSC handheld.

Before DSC we kept the volume sufficient to maintain a listening watch on deck whilst allowing the crew below to sleep. What's wrong with that?

The DSC equipment spec is just plain ill-conceived and should be changed.

 

[Talulah]

Here, here.

 

[ShipsWoofy]

Copied from PBO as two threads running

I disagree with the opinions that a volume control should be fitted. Although the problems are mainly that the alarms wake up off watch crew. Once a DSC all ships has been sent you will still have to visit the radio. The moment you acknowledge the call whatever your radio was doing prior to this will be reset and it will be sat there waiting for any voice messages on 16.

So you have to acknowledge and consequently reset your radio back to dual watch, tri watch etc. This as much as the alarm can be a pain in neck. Especially if as our South Coast buddies are saying they are getting alarms every 15 minutes or so. It may cause a skipper to miss an important port op's message on ch12 for example.

We do not need volume control IMHO, we need certain stations to be a little more judicious on their use of DSC alerts.

As to waking off watch crew, there is always the option of switching off the internal speaker and having only the cockpit speaker running. But I still think some education to those stations which cause regular problems to be the way forward.

Ooop north, the only DSC alerts I have heard have been from Holyhead CG warning of imminent gales, the jury is still out for me as to whether I want this or not, on the mooring it is a pain (where I have heard them so far) but on passage, I think it might be welcomed, I don't know.

 

[tome]

Sorry, but you obviously haven't experienced the problem.

There is no option to switch off the internal speaker regardless of whether a cockpit speaker is connected.

Having a volume control would allow the on watch to prioritise (yuk!) their response to the radio with other tasks, instead of being forced to dive straight for the set in order to silence it.

<The moment you acknowledge the call whatever your radio was doing prior to this will be reset and it will be sat there waiting for any voice messages on 16>

Just plain wrong. When you acknowledge a DSC alert the set will go to whichever channel has been selected by the originator of the alarm.

Not one of your best posts!

 

[Sgeir]

[ QUOTE ]
The DSC equipment spec is just plain ill-conceived and should be changed.

[/ QUOTE ]
The trouble then would be another new standard, probably even more complicated, with the possibility of legal enforcement.

I share the criticism of DSC with the attendant false alarms, miscalls, and unnecessary alerts. And it's not just leisure sailors, the fishermen appear to be equally fed up/baffled.

While I strongly agree that Ch16 should be maintained as the prime listening channel, I see absolutely no prospect of the various agencies undoing the technology or the requirements. To do do so would call into question the entire manufacture/distribution/sales/fitting processes of the recent period. Would they compensate for all the upgrades that have been fitted over the last few years? I doubt it.

Unfortunately, I think we'll just have to get on with it and get used to it.

 

[ShipsWoofy]

[ QUOTE ]
There is no option to switch off the internal speaker regardless of whether a cockpit speaker is connected.

Having a volume control would allow the on watch to prioritise (yuk!) their response to the radio with other tasks, instead of being forced to dive straight for the set in order to silence it.

[/ QUOTE ]

Ok, mine does, I honestly thought this was a standard function. scrap that then. Though I don't know if turning off the internal speaker does all it says on the tin, knowing regulations, I would not be surprised if this was over ridden if an alarm came in.

[ QUOTE ]
<The moment you acknowledge the call whatever your radio was doing prior to this will be reset and it will be sat there waiting for any voice messages on 16>

Just plain wrong. When you acknowledge a DSC alert the set will go to whichever channel has been selected by the originator of the alarm.

[/ QUOTE ]

Ok, you are right, not 16 but for example 67, it is the same motive though, during the alarm the radio is no longer receiving (or does not appear to be) any other traffic. At the moment you acknowledge you are removed from what the radio was doing prior to the alarm. My mistake on saying 16, wrote in haste.

[ QUOTE ]
Not one of your best posts!

[/ QUOTE ]

I agree but for a few small errors. But I still stand by the problem is not entirely the radio, but misuse by a few who are sending messages every 15 minutes to warn of a firing range.

No one has ever said for example, I do not want to hear mayday calls during the night. I have still to hear anything but a sécurité regarding weather, got the radio late last year.

 

[Robin]

Many sets that I have owned in the past had switches for the internal speaker, but would NOT switch off the internal speaker if an external one was plugged in, so quite what the point of the switch was escapes me. The problem anyway is that you still have to go to the set to shut it up by acknowleging the call, and in bad weather especially that can get tiresome every 15 minutes, as can being woken up every 15 minutes when off watch, isn't that considered 'torture' under the Geneva Convention? Yes it would be much better if the folks setting off alarms were more responsible but there are lots of culprits, from Traffic Control Centres, Coastguards, Navy vessels, cable laying and survey ships and so on. Plus as someone else said there is a world of difference in the volume required on the bridge of a ship or the flybridge of a noisy mobo and that required in the quiet of a cabin on a yacht! It is irritating in the extreme that a committee of 'experts' has decided that we are not capable of adjusting the volume ourselves to suit the circumstances, therefore has fixed the volume at a level guaranteed to waken the dead and eventually cause us to turn the set OFF!

To put the Mayday alarm into perspective, I did not hear one single Mayday DSC Alarm last season. If I did it would be entirely appropriate, no complaints whatsoever! I DID hear 'n' hundred alarms for messages relating to (say) deep draft vessels or tugs/tows etc in the Casquets TSS 60 mls away! And I heard dozens of 'ghost' alarms, where the alarm screams and nobody is there...... but the set has been hijacked to CH80 which suggests it was Joburg Traffic who are out of voice range but in the alarm signal range on CH70, which works at longer range since the channel is kept clear of all other traffic. Thing is stations like Joburg have big aerials on cliff tops/hills so have huge range even on VHF line of sight. We normally receive Joburg loud and clear in Poole 60 miles away, it isn't just an unusual propagation such as high atmospheric pressure (when we can receive Brixham and Falmouth CGs, Dover CGs and so on.

 

[Sans Bateau]

Those of us who now own DSC sets are stuck with them. Modifications to the hardware for future sets will not help us. That isn’t the answer though; the main problem appears to be the unnecessary transmissions of weather reports etc that do not warrant a DSC alert, driving people to turn their sets off. One of my reasons for fitting DSC is safety. As the situation stands today, myself nor any other user of DSC is any safer with its installation, to the contrary.

If there are issues with the use of DSC on our boats, then we need to sort it out. With the main cause being something out of our control then we need to, as I suggested earlier address it with the MCA, let’s start writing.

 

[Sans Bateau]

Those of us who now own DSC sets are stuck with them. Modifications to the hardware for future sets will not help us. That isn’t the answer though; the main problem appears to be the unnecessary transmissions of weather reports etc that do not warrant a DSC alert, driving people to turn their sets off. One of my reasons for fitting DSC is safety. As the situation stands today, myself nor any other user of DSC is any safer with its installation, to the contrary.

If there are issues with the use of DSC on our boats, then we need to sort it out. With the main cause being something out of our control then we need to, as I suggested earlier address it with the MCA, let’s start writing.

 

[Oldhand]

Firstly Tome, my DSC VHF alarm is not as piercing as you seem to suggest, so choosing the right equipment to suite your requirements would seem an appropriate consideration.

Secondly, if you think hard about the installation, as I did, and end up with a full control dual station installation, then it is possible to have equipment with which you can turn the cabin installation sound off, either by a mute function, a physical switch or both. If that is still too much for you, then the external speaker can be turned off such that only the tiny speaker in the handset provides any audio output - at the risk of missing a distress alarm.

It just takes a little time and thought to arrive at an installation which suites one's needs rather than just buying a cheapie and mounting it in the same place as the old non-DSC VHF, usually at the chart table. I don't see why public protest needs to be an alternative to this. /forums/images/graemlins/shocked.gif

 

[Oldhand]

<So you have to acknowledge and consequently reset your radio back to dual watch, tri watch etc.>

You don't have to acknowledge an alarm on my DSC VHF, one has the option to "Clear" which means it returns to the status before receiving the alarm. So, I just read who initiated the alarm and what type of alarm it is and if I don't want to hear the subsequent broadcast, a single button press is all that is required. You might wish to check if your equipment allows a "clear" function. /forums/images/graemlins/smirk.gif

 

[Oldhand]

<Not one of your best posts!>

Not one of your best one's either, anybody can install a switch in their loudspeaker wiring so its up to you to install the option, if that's what you want!

 

[tome]

<rather than just buying a cheapie>

Not sure that Simrad would class my RD68 as a cheapie Oldhand. I certainly didn't.

OTOH, I've always been happy with a single dedicated VHF set until now and have no wish to install a network of handsets just to overcome a basic fault in the equipment specs. As a design engineer I have to face the old dilemna: double the equipment and halve its reliability.

 

[tome]

Oldhand, you haven't understood the problem.

The external speaker (fitted in the cockpit) isn't an issue. It's the fact that it doesn't disconnect the main set below when in use, unlike the traditional sets. Switching off the external speaker achieves diddly squat.

 

[Robin]

[ QUOTE ]
Firstly Tome, my DSC VHF alarm is not as piercing as you seem to suggest, so choosing the right equipment to suite your requirements would seem an appropriate consideration

[/ QUOTE ]

Of course you knew this prior to purchase, I expect you had the dealer demo the alarm sound/volume to you?

[ QUOTE ]
Secondly, if you think hard about the installation, as I did, and end up with a full control dual station installation, then it is possible to have equipment with which you can turn the cabin installation sound off, either by a mute function, a physical switch or both. If that is still too much for you, then the external speaker can be turned off such that only the tiny speaker in the handset provides any audio output - at the risk of missing a distress alarm.

It just takes a little time and thought to arrive at an installation which suites one's needs rather than just buying a cheapie and mounting it in the same place as the old non-DSC VHF, usually at the chart table. I don't see why public protest needs to be an alternative to this.

[/ QUOTE ]


Firstly all the sets that are on sale are supposedly designed by experts for use with the new DSC system by leisure sailors. They go through a 'Type Approval' process which a) prevents us from buying cheaper sets out of for example the USA (where dual station sets ARE cheap) and b) according to the dealers in Europe is why the prices here are that much higher. Yet these sets are like the committee designed horse now better known as a camel, why? Because the Committee decided we users were not responsible enough to set an alarm volume level correctl, therefore all sets must have a fixed, non-adjustable full volume alarm, no other option.

Secondly, why do you keep referring to Distress Alarms? If these were Distress Alarms we hear, there would be no complaint - fill the skies with flares the airwaves with DSC alerts and EPIRB calls, that is entirely justified, no argument. The fact is after around 2,000mls last season I did not hear one single solitary Mayday DSC alert! But I did hear screaming alarm after screaming alarm for navigational warnings mostly affecting areas many miles away like Joburg Traffic ones for the Casquets TSS. Now Joburg and the other Traffic Control Centres all have the ships in their areas logged, by the new wunderkinder AIS as well as Radar plotting and VHF interrogation. Using AIS they HAVE the MMSI numbers of ALL the ships in their area, they could surely take these from their computers and just send their DSC Navigational Warning to those ships, this is a feature that is promoted of DSC, the 'group' calling option. But no, they don't do that they put out a screaming alert to everyone within maybe an 80ml plus radius and repeat it every 15/20 minutes!

I have had VHF on board my boats for around 25 years. A set mounted below in the dry at the chart table has always been more than adequate, backed up by a cockpit speaker. We rarely MAKE VHF calls these days so there is no need for a cockpit mounted control head, those are for the seagoing equivalent of mobilephone users aren't they, personally I go sailing to escape from telephones!

Now over on the other side of the pond in the land of cheaper radios, they don't even have DSC yet. The International rules may call for it but the US Coastguard hasn't built any DSC listening/transmitting stations so it remains unused. This whole thing is an awful mess and phase 2 of this is that CH16 is to be removed as a calling channel 'because everyone can call each other by DSC and their MMSI'. So no calling channel (in their dreams because people WILL continue to use CH16 IMO) and unless you know the MMSI of that ship coming at you it isn't possible to call him on CH16 'cos he's not listening. Oh but then you now open box of tricks #3 and switch on your new AIS receiver, get his MMSI and then type this into the DSC VHF (if your fingers aren't too cold/wet) and send him a 'request' to talk with you via Ch77 or whatever, always supposing he isn't too busy trying to run you down. As I said, IMO this is a full blown all out mess.

 

[Oldhand]

It seems you are suggesting you are not capable of undoing a few screws, locating the speaker wires and either rewiring such that the external speaker jack disconnects the internal speaker or taking a speaker wire to the outside world so you can put a switch in a circuit. I can understand how to do that...