NAVTEX - is its time up - at last?

[lw395]

I find it quite useful even pottering around the edges of Europe.

I think the BBC are floating a similar illogical wheeze with Long Wave voice radio, viz

1) It's really very old primitive technology

2) It would be very difficult, if not impossible, to replace when it busts

Basically it uses a lot of power and expensive equipment to get 'the archers' to a few dozen luddite expats in France. Who don't pay the licence fee and whine about the story lines anyway.
Long wave transmitters are bespoke items, expensive but not exactly difficult technically.
Nobody holds stock of monster valves any more, but solid state technology is available.

 

[GHA]

Lots of people going transatlantic using devices like Garmin InReach - circa £300 and very compact. Satellite technology is advancing.

Can they send gribs?
Though gribs on their own are handy weatherfax really comes into it's own midocean - see the whole north atlantic synoptics & 500mB charts for free once you have a receiver.

 

[franksingleton]

All very interesting. I had guessed that USCG was referring to INMARSAT which, as we all know is not suitable for most yachts. Nor would it be affordable for many small commercial vessels. This is a general problem, not just a leisure yacht one. I tried to get publicity for the problem of GMDSS generally in a Navigation News article in January 2005but had no response.

To me, it seems the most likely outcome is based on the hope that satellite telephones become and services become more affordable. In parallel we would need GMDS information URLs to be reliable and unchanging so as to be reliably accessible. That is something that IMO/WMO could take steps to ensure. The ideal, probably unattainable, solution would be a dedicated GMDSS website that, somehow, would be free to access, continually updated and carrying all GMDSS information. Could telephone calls to such a site be free? The main drawback vis a vis the GMDS concept is that it would be a pull rather than a push system.

Quo vadIs?

 

[Zing]

The alternative to Navtex is weatherfax or Inmarsat C, or data via a satellite phone or data link. I find weatherfax superior anyway and won’t miss Navtex. If near-shore you almost always can get mobile data too, or even the shipping forecast, so there should be access to all you need and cheaply if you want.

It is going just in the US anyway and over there Navtex never caught on like it did in Europe. Different strokes, different folks.

 

[JumbleDuck]

I think the BBC are floating a similar illogical wheeze with Long Wave voice radio, viz

1) It's really very old primitive technology

2) It would be very difficult, if not impossible, to replace when it busts

According to the Guardian in 2011, continued LW transmission depends on having a pair of transmitter valves of which there were then only ten left and which lasted between 1 and 10 years.

 

[lw395]

According to the Guardian in 2011, continued LW transmission depends on having a pair of transmitter valves of which there were then only ten left and which lasted between 1 and 10 years.

Imagine! The Archers forced to go solid state!

Still, in Scotland you have Burghhead and Westernglen transmitting the same (mostly) nonsense, no doubt McWebby will want that wavelength for independent Scotland when Droitwich wears out?

These days there are many better ways of generating 198kHz, but why bother? It's very inefficient using 500kW to transmit very little bandwidth.

 

[Never Grumble]

We have a NavTex unit on our yacht, I know what it does but I have no idea how to make it provide the information I want, all of which for a coastal sailor is more easily found on the web. It no longer troubles me as I took the fuse out so it doesn't even draw any charge. One day I might attempt to work it out, but I think that could be a long way off.

 

[Pye_End]

These days there are many better ways of generating 198kHz, but why bother?

range + cheapness of receiving equipment.

 

[RobbieW]

...
These days there are many better ways of generating 198kHz, but why bother? It's very inefficient using 500kW to transmit very little bandwidth.

So that SWMBO can listen to TMS running down the coast of Portugal !

 

[franksingleton]

Clearly, from the posts above, many of us have our pet likes and dislikes of the various current channels by which we receive marine safety information. Salient facts are that:

1. Analogue radio will cease in the not too distant future. So R4 LW will cease whether we like it or not.

2. Teletext (RTTY/SITOR/NAVTEX) will cease in the not too distant future. So will Radiofax.

3. Inmarsat is not suitable for many small craft both leisure and professional.

So, questions that should be being addressed:


What will replace these for GMDSS information?


Who is representing the needs of these highly vulnerable groups at government and international marine Forums

Do we have to accept that marine authorities will just assume that we will all reconcile ourselves to using the internet as our source of GMDSS?

If so, how will they ensure that internet services are robust and reliable?

Will they ensure that equipment and operating costs are affordable to all small craft owners?

Failure to ensure the last two requirements will mean that they are abandoning the underlying principles and concepts of SOLA/GMDSS.

 

[cpedw]

1. Analogue radio will cease in the not too distant future. So R4 LW will cease whether we like it or not.

How will the trident subs know not to fire?

 

[lw395]

Clearly, from the posts above, many of us have our pet likes and dislikes of the various current channels by which we receive marine safety information. Salient facts are that:

1. Analogue radio will cease in the not too distant future. So R4 LW will cease whether we like it or not.

2. Teletext (RTTY/SITOR/NAVTEX) will cease in the not too distant future. So will Radiofax.

3. Inmarsat is not suitable for many small craft both leisure and professional.

So, questions that should be being addressed:


What will replace these for GMDSS information?


Who is representing the needs of these highly vulnerable groups at government and international marine Forums

Do we have to accept that marine authorities will just assume that we will all reconcile ourselves to using the internet as our source of GMDSS?

If so, how will they ensure that internet services are robust and reliable?

Will they ensure that equipment and operating costs are affordable to all small craft owners?

Failure to ensure the last two requirements will mean that they are abandoning the underlying principles and concepts of SOLA/GMDSS.

The switch-off of analogue radio seems to be receding?
The commercial fact is that FM stations make money and buy spectrum licences.

Not that mainstream commercial broadcast has much to do with LW anyway.

AIUI, weatherfax can be received from a statellite in the Atlantic, using a laptop and a cheap 'software defined radio'.
Somewhere around 140MHz, between the air band and the 2m amateur band?

Over the years, I've seen so much stuff debated and proposed, I've lost the plot as to what is actually happening.

 

[lw395]

range + cheapness of receiving equipment.

198kHz AM could be generated without the use of valves. The Irish LW station was nearly as powerful and had a brand new transmitter about 12 years ago. It's not some forgotten art that can't be replaced!

 

[GHA]

AIUI, weatherfax can be received from a statellite in the Atlantic, using a laptop and a cheap 'software defined radio'.
Somewhere around 140MHz, between the air band and the 2m amateur band?

Never heard of anything like that, guessing if it was real it would be fairly well known amongst cruisers as it would be really handy, rtl dongles don't go low enough for wfax broadxasts.
Nothing on the rfax schedule doc either.
any links?

 

[Roberto]

Never heard of anything like that, guessing if it was real it would be fairly well known amongst cruisers as it would be really handy, rtl dongles don't go low enough for wfax broadxasts.
Nothing on the rfax schedule doc either.
any links?

I think LW refers to Satellite weather imagery rather than weatherfax, a few NOAA orbiting satellites transmit around 137MHz, they can be received by SDR dongles, though it is a very different product with regards to weatherfax.

 

[GHA]

I think LW refers to Satellite weather imagery rather than weatherfax, a few NOAA orbiting satellites transmit around 137MHz, they can be received by SDR dongles, though it is a very different product with regards to weatherfax.

Ah yes, done that, noaa17 think it was. Manually adjust for the doppler as the satellite goes tick toc overhead.
Fun and maybe a little useful but nothing compared the weatherfax synoptics. Should be possible to get wfax images from the Web with sail docs but would end up being a lod of data. Or even have some python running online to go grab them and compress in a page or 2. Would be very sad to lose wfax. Adds some fun to the day when it's time to turn on the radio and get today's latest.

 

[pagoda]

Navtex is free and authoritative, and very useful. I hope they don't get rid of it.

I agree. Waking up to find a recent inshore waters forecast without relying on internet or VHF transmissions is thoroughly handy. There are still fair sized holes in GOOD internet coverage on the West of Scotland. Ireland we found considerably better.

 

[Amulet]

I would miss Navtex. I installed it some years ago, when the CG were playing silly buggers, and refusing to issue Safety Information.
I sail on the West Coast and Hebrides. Some of the time I have Internet, some of the time I have the Inshore Forecast via VHF from the CG, some of the time I get Navtex. Usually, but not always, I can get at least one of the three. Obviously the most useful is the Internet, the CG don't do the forecast if they're busy, and Navtex is dodgy if close under high land, but has the great advantage that it records, and can be read later. So yes, I would definitely miss it.

Me too. I'm not a particularly intrepid sailor, but my Western Isles sailing occasionally causes me to spend a couple of days in pockets of no phone or internet, and at that time I use Navtex as my source of weather info. It is by no means my main source, but it is sometimes my only source.

 

[Gwylan]

Well, NAVTEX is like Marmite.

But more useful. Get the kit set up and it does the necessary. That and the barometer.

What did the NASA NAVTEX cost when it was launched? What does that translate to in today's value.

Do need a some, reasonably priced system for receiving weather forecasts in a manageable format.

 

[franksingleton]

I agree with many of the comments above. I have had NAVTEX on our boat for many years and would not be without it although I do not see it with such rosy eyes as some. It is far from being totally reliable. Nighttime sky wave propagation is an intractable problem. In our Med days we had numerous occasions quite near to Toulon when we received Valentia, SW Ireland. also ID W, and, near Tarifa, receiving Cullercoats instead of Tarifa. Reception near the coast can be poor and in port. The specified requirement is for reception from the fairway buoy to about 200 mile out to sea. I have always advised that it should be carried as an integral part of the GMDSS.

From my experience in recent years, I would hazard a guess that far more sailors rely on the internet than use NAVTEX, But, that is not the point that I was raising in the OP. Terrestrial marine radio has its problems and an uncertain future - the USCG notice shows that. The intenet has become a de facto source of GMDSS information. As such it should be robust and reliable. Although pretty good, it is currently neither. That seems not to be recognised by IMO/WMO.