VHF/GMDSS

Please don't confuse GMDSS with DSC.

GMDSS is the system that encompasses all aspects of Maritime radio communications. Just to be clever, even if you use a 406 EPIRB you are still buying into the GMDSS!

DSC is just the calling protocol now used by MF/ HF and VHF Marine radio equipment.

Mike

Manager,
Aeronautical & Maritime Section,
Radiocommunications Agency
 
The rules are clear it will be monitored where a "danger of collision exists" it will not be available for general calling that is the job of Channel 70 using DSC.

In the same way that you used to call all ships using Pan or Securite on C16 you still can using DSC All Ships, the users in range would then go to C16 so that the voice or working can begin.

As my colleague Steve Huxley at HMCG always says "and if that doesn't work you can always bounce a red off his bridge"

Mike

Manager,
Aeronautical & Maritime Section,
Radiocommunications Agency
 
Satisfied user but...

Bye and large I've come to appreciate DSc.

I have only one quibble, which is that it is not possible to live test the distress function.

I'm sure the current plethora of "radio check" traffic on Ch16 is because the avg small boat sailors seeks the reassurance that if he has to make a shout, the kit will work. Hearing a CG saying "receiving you loud and clear" provides that reassurance.

With DSC you can run a self-test diagnostic on the kit, but it doesn't provide the actual comfort factor of knowing that you've actually got through to the man or woman in the big chair. Which does mean that putting out a DSC mayday is a considerable act of faith in the kit and certainly makes me a little trepidacious.

Is it acceptable to DSC call a coastguard MMSI to request a working check (picking a quiet time, obviously)?
 
Re: Satisfied user but...

Good point Ken. It would have been great if they could have built in a 'Radio Check' feature into DSC to take the clutter off the open channel 16. That might persuade more Solent sailors to upgrade, as they could leave the radio on low, and keep all the chat silent.

You've not published your MMSI on your profile, BTW

Jeremy Flynn
 
Mike
I am sure we all appreciate your input into this debate & I for one want to say thanks...... butttt........ yes there had to be a but!


Please don't get me wrong I am all in favour of the new system, being a bit of a techno freak, otherwise I would'nt have taken the course. My only worry is that the uptake, or lack of, of the new equipment will by default render it useless (For small boats)
I am sure that most users on here, by the very fact that they are interested enough to contribute on the forums, will be investing in VHF/DSC sets. My worry was the fact that if channel 16 was to be downgraded to a listening watch only, will it put lives at risk, I think the answer must be yes IMHO.
Also the fact that other vessels will NOT be monitoring ch16 in 2005 and only using DSC for Urgency and Emergency will also put lives at risk.

Yes I agree that it is up to the individual to keep themselves safe at sea but I am sure, as is the case in most leisure pursuits, that advances in technology are not taken up by the many but only the dedicated few.

My golf partner still plays with a set of clubs that are nearly 40 years old.

Soap box ..... what soap box?


poter
 
Re: Satisfied user but...

The official line is that the self test function on DSC sets is more than sufficient to test that the electronics are in working order. This of course reduces extraneous (good word) work load of HMCG personnel who are monitoring for Distress calls.

However, if you are someone who "needs" the comfort of a voice at the end of the line, so to speak. You are advised by HMCG to call another vessel. The circuitry that enables the Distress and All Ships calling functions is exactly the same part that enables routine individual vessel calls.

An idea popped into my head, so I have just checked with Falmouth MRCC and they agree that of course the perfect way to live-test your DSC is by lodging your passage reports with HMCG!!

Mike.


Manager,
Aeronautical & Maritime Section,
Radiocommunications Agency
 
At the end of July I returned from Brittany to North Wales, encountering thick fog, visibility 2 cables or less, while crossing the exit from the Ushant southern shipping lane. Ushant traffic control was warning of the fog and also frequently calls up ships by position who have not reported in. What channel will they use for this?
There was a stream of ships eastbound from the southern lane, none of whom where making fog signals or reducing speed. Thanks to radar, I was able to turn away from one threatening situation, but one of the next pair of ships, with one overtaking the other, became an unavoidable threat, at 5 knots, on my port side on a steady bearing. I called on 16 with my position twice and the ship altered to pass about 3 cables away on my port quarter. In the future does one call on 16 or 13? In an emergency it is vital to do it on the right channel.
Referring to the article in the August YM about the passage to the Canaries and rounding Ushant with GPS and no radar in fog, my recent experience convinces me that to attampt it without radar is very unwise.
 
I agree 100%. In technical terms, it's 1970s technology (I used to operate a PMR 'Selcall' system back in those days).

That said, I've not bothered to change the set for one with DSC (although I've got the license). Basically, until the US starts adopting it big time, decent sets for the right price are simply not going to come through, because its not worth the manufacturers building 'em

One thing on the horizon that I do think will change things is the advent of IFF-style 'responders' (like on Aircraft) which will identify ships on radar with a specific code. I gather this is in the works for the professionals, and a group is working on a small-boat version which uses a version of the DSC set to send the code.
 
International VHF frequencies are as follows ( these are the main ones )

Ch 16 Distress, Safety and contacting CG
Ch 67 Small ship safety channel ( but uk only)
Ch 13 Bridge to Bridge working channel
Ch 70 Digital selective calling ONLY
Ch 06 08 72& 77 intership channels
Ch 10&73 CG met. & safety.
Ch 80 marina's ( UK only)

Harbour Authorities for instance Dartmouth Ch 11 but refer to almanac.

Hope this helps.


poter.
 
See my post further up this thread. Listening to Ch 16 off Holland and Belgium it is evident that the vast majority of ships call each other and remain on 16. They may also monitor 13, I have no idea, but 16 seems to be the channel of first choice.
 
Re: Satisfied user but...

Has anyone noticed that (certainly in the Solent) one of the first questions the CG asks is "is their a mobile on board?..can I have the number". Maybe this says something about our analogue VHF technology.....especially where other agencies such as the police etc are involved.

It does grate on me the way DSC is promoted as 'digital' technology, when it is nothing more than analogue tones sent over your analogue VHF set! (same technology as your touch-tone phone you've had for years.)
 
Re: No

I haven't heard that question either!

However, I can tell you why they want to know. HMCG wants to know about every bit of comms kit available during an emergency it is not because a mobile is in any way superior or more useful as it isn't (can't be DFd, can't call other vessels etc) but it does have integral power and antenna and therefore may be still operable if vessel goes under.

This is exactly why the Ship Radio Licence registers all transmitters on-board and why we give the info to HMCG every week.

Mike

Manager,
Aeronautical & Maritime Section,
Radiocommunications Agency
 
I would say that the US effect has already happened there is already an all-in set on the UK market (I've just checked a couple of mags) and it's being sold for approx £260.

Yes the Automatic Identification System is nearing general roll out with some port operators getting close to the end of their trials.

Mike

Manager,
Aeronautical & Maritime Section,
Radiocommunications Agency
 
Re: Satisfied user but...

I use DSC to call Solent Coastguard when giving a passage report cross channel. It is easier as they call me when they are ready. However, the DSC 'prod' can be received by them when still outside voice range so one can not then complete the exchange. I also use it ship-to-ship when possible. The only problem is the noise from such things as an all ships saying a 'pan-pan' has been teminated etc., I would have thought 16 would do for that but guess rules say otherwise?

J Webb
 
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