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04-08-2014, 23:40
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#1
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Registered User
Join Date: May 2007
Location: Florida
Boat: Catalina 470
Posts: 2,595
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Marine HF-DSC-SSB, the GMDSS, "communications stool legs"
I've had success!!
(I couldn't get the links to videos to work here on cruiser's forum, nor could I get the paragraphs to actually post correctly/in order....and that's even breaking the posting up into multiple parts and posting it as a new thread!!)
So, please see this SSCA posting....
Marine HF-DSC-SSB, the GMDSS, "communications stool legs"
Dan, you're very welcome!! (and yes, if I had more time, I would've written less!!)
Quote:
Originally Posted by Ex-Calif
You might want to think about putting a few canned messages together to guide the "newbie." I mean simple stuff.
I have tried this here before....without much success...
I posted some great detailed facts/info, with many official links, etc. regarding Offshore Weather info/forecasts, and the very first responses / replies didn't say "thanks" or "wow", but criticized my use of the word "accurate" in the thread title....and then it went downhill from there, with pages after page of various opinions and criticisms, but nobody ever disputed the facts!!
The problem was that nobody ever bothered to read/understand the facts, nor follow the links, etc....
So, while I still think putting together a "newbie's guide to HF comms, offshore weather, etc." and details on exactly how handheld sat phones work, and their limitations....
The unfortunate outcome would most probably not make much difference, except for wasting my time!!
BTW, the only reason that my thread with the HF Radio Videos "survived", was because a Cruiser's Forum Moderator was just starting to install/use their own M-802, and found the videos helpful....so the made them a "sticky"...
For one small yacht successful installation of MF/HF-DSC installation I would recommend - Radio X, Antenna Y - mounted Z. You also need A-B-C.
All of this is already posted here....and much is in my HF radio videos thread/"sticky"....
But, in a nutshell....here is what I've using/posting/recommending for years...(it is no secret, and it all works very well!!)
Radio/Tuner: Icom M-802, and AT-140.....
Antenna: Insulated backstay, 40' - 45' long (or "alternative backstay antenna").....
{longer lengths (50' - 60') favor the lower bands (4, 6, 8, and are still good thru 12mhz), but have a slight disadvantage on the higher bands....shorter lengths (25' - 30') favor the higher bands (16, 18, 22, and 25mhz), but have significant disadvantages of the lower bands!!!
So, 40-45' is good for most....(mine is 63'...as I prefer to favor the lower bands....)}
RF ground / antenna ground: 3"-6" wide, < 8' long copper strapping to clean underwater metal / Dynaplate / Thru-hull, etc....(alternatively, use toerails, lifelines, pushpits, pulpits, stanchions, metal tanks, keel bolts, etc. tied together, using copper strap, as a counterpoise...)
Use THICK copper strapping, not thin foil, and paint it (except for the connection points), and it will last decades!!!
(and use Penatrox-A, conductive/waterproof grease on the RF ground connections....and they still be in excellent shape for years and years...)
Follow Sailmail's installation recommendations....and read/study the Sailmail Primer (even if you'll never have a PACTOR modem, nor HF e-mail at sea)
http://www.sailmail.com/smprimer.htm
After the radio is successfully installed here is what you should do to ops check things.
Watch the videos and ask questions....
http://www.cruisersforum.com/forums/f13/icom-m-802-instr-videos-basic-adv-and-live-dsc-distress-call-114734.html
To get voice weather in your area try these channels and these times - to get email working do this. To get weather fax do this.
Read this discussion and follow the links (and read them)...
Offshore / Hi-Seas Weather data / forecasts
I am not smart enough to write this up but I can see real value in a simple "Dummy's Guide to installing "SSB" and getting it going.
Dan, it is already there on-line....free for the taking....(see the info above, ESPECIALLY the Sailmail Primer.....read the above threads/discussions and the links there in....and it is all there, no need to write a book, or reinvent the wheel!!)
But, you do understand that, "you can lead a horse to water, but 'ya can't make him drink"!!
I say I'm not ready for MF/HF yet because I am coastal sailing for now well within range of both VHF and cell phone coverage. But I'm learning!
I'm glad to be of help....just know that all the info is right there for 'ya....no need for anyone to write a book....(and it's all FREE!!)
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Fair winds...
John
s/v Annie Laurie
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18-08-2014, 13:18
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#2
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Registered User
Join Date: May 2007
Location: Florida
Boat: Catalina 470
Posts: 2,595
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Re: Marine HF-DSC-SSB, the GMDSS, "communications stool legs"
It is surprising that nobody has replied/commented here, yet...
When the topics of "SSB radios", "Distress signaling", "Bluewater boats and communications", "sat phone vs. SSB", "HF radio", "DSC", "digital communications", "offshore weather", "e-mail", etc., come up on here, there are dozens of replies / comments....(and here with it all in one place, nothing??)
I get at least one direct e-mail each week, and at least one PM here each week, and used to get at least one SSCA PM each week, all asking about HF-DSC and the GMDSS, etc.....
And, recently was asked by multiple folks to try to lay everything out in one succinct posting....
So, I did just that....and have linked to all of that info here, just one click away....
Marine HF-DSC-SSB, the GMDSS, "communications stool legs"
But now that I tried to lay out much details about these topics, in one succinct posting (and how we "cruiser's" can use the GMDSS to our great advantage, etc.).....after 2 weeks, nobody has anything to say about this???
I'm NOT trolling for compliments!!! (nor criticism!! )
This is NOT designed to be a substitute for proper training, GMDSS certification, etc....NOT at all....
I was just trying to put together all the info (and some advice), in one place that you all could refer to and gain knowledge from...
And here, I'm just trying to see if anybody has read it all, watched everything, and has any questions....
If not, no worries....
Fair winds...
John
s/v Annie Laurie
P.S. FYI, I tried multiple times to get this info/posting to display here on Cruiser's Forum, but was unable tp do so....so, I posted it, in its entirety, on the SSCA Discussion Boards, Communications forum....
It is a simple one-click away....
Marine HF-DSC-SSB, the GMDSS, "communications stool legs"
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18-08-2014, 13:37
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#3
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Nearly an old salt
Join Date: Jun 2009
Location: Lefkas Marina ,Greece
Boat: Bavaria 36
Posts: 22,801
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Re: Marine HF-DSC-SSB, the GMDSS, "communications stool legs"
John, Great set of posts,
I would of course have the typical issue that you are a bit biased against satphones, but hey line and let live
dave
__________________
Interested in smart boat technology, networking and all things tech
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18-08-2014, 16:14
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#4
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Registered User
Join Date: May 2007
Location: Florida
Boat: Catalina 470
Posts: 2,595
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Re: Marine HF-DSC-SSB, the GMDSS, "communications stool legs"
Thanks Dave...
No worries here...
Yeah, I guess we all have our little "biases"....
Since the thrust of my post was primarily about explaining when we write/talk about "SSB", we are talking about "MF/HF-DSC-SSB".....as well reinforcing the idea of using as much as of the GMDSS as we can, on-board our cruising boats...I didn't mention too much about sat phones, but I did mention was positive!!
I did write this....
Quote:
This means that with just a press of a button or two, your MF/HF-DSC-SSB Radio is sending out very detailed/accurate position information, as well as your MMSI# (which gives the shoreside RCC's all your vessel info, size/type/color, equipment on-board, communications capability, liferaft/survival craft, etc. as well as your shoreside contact information), and if you've selected a "distress type", the exact nature of your distress....AND it is waiting for an acknowledgement of your DSC call on both the GMDSS DSC channel/freq and on the appropriate GMDSS Voice SSB channel/frequency....AND it does this automatically....
Again, all automatically, without any need for "trained" / "experienced" radio operators....
And, this is/was one of the basic goals / principles of the GMDSS....allowing multiple / redundant (and robust / reliable) ways of signaling shore stations and other vessels, WITHOUT the need of trained radio operators....
Using 406mhz EPIRB's, VHF-DSC, MF/HF-DSC, INMARSAT-C, allows for all of these goals to be realized!!!
(although many/most cruiser's feel not having INMARSAT-C is not too much of a detriment, and some compliment the other GMDSS equipment with a consumer sat phone, such as Iridium, and feel this adequate for them..)
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Dave, thanks for taking the time to read all that stuff....
And finally....anyone that watches that old (1992) GMDSS video please remember two things...
a) the GMDSS is not new, and we "cruiser's" should have been using as much of it as we can afford, for more than 15 years now....(and many have been equipping with 406 EPIRB's, but unaware of the other affordable aspects/features...)
b) ignore the old/outdated info in the video (that I mention in the text describing it), and remember that the "new" stuff (GPS-enable 406 EPIRB's, the Icom M-802, inexpensive NAVTEX receivers, and INMARSAT-C terminals, etc.) are all much more modern and user friendly than that "old" stuff shown in the video!!
Fair winds...
John
s/v Annie Laurie
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18-08-2014, 17:03
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#5
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Registered User
Join Date: Oct 2011
Boat: Valiant 42
Posts: 6,008
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Re: Marine HF-DSC-SSB, the GMDSS, "communications stool legs"
John,
It's amazing to me that just because the base technology of SSB and HF band radio is so 1940's that people assume it's really hard to use or is not reliable. Some people tell me that they thought shortwave was no longer usable because of (sunspots, Fukushima, climate change, HAARP, pick the latest "disaster" in the news). I continue to be amazed at some of the nonsense I hear.
I fear that the next generation will ignore HF altogether and never realize its capability. In a couple of generations after that someone will "invent" an amazing new technology. It will let you send voice, text and email half way around the world without satellites or roaming fees. They'll probably call it iWave and end up owning a 500 foot motor yacht by the time they are 24.
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18-08-2014, 17:45
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#6
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Registered User
Join Date: May 2007
Location: Florida
Boat: Catalina 470
Posts: 2,595
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Re: Marine HF-DSC-SSB, the GMDSS, "communications stool legs"
Dan,
iWave??
I like the way you think!! (let's see if we can patent ionospheric skywave communications...)
Quote:
Originally Posted by transmitterdan
I fear that the next generation will ignore HF altogether and never realize its capability. In a couple of generations after that someone will "invent" an amazing new technology. It will let you send voice, text and email half way around the world without satellites or roaming fees. They'll probably call it iWave and end up owning a 500 foot motor yacht by the time they are 24.
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But seriously, I do have some REAL info about the REALLY LONGTERM prospects of HF skywave communications....and by "really longterm", I talking centuries / millennia into the future (maybe even millions of years from now...)
You see, even the planet Mars has an ionosphere....originally proven by NASA's early probes, such as Viking, in the 1970's....and still being studied by physicists / professors at various universities, NASA, and the ESA....(the ESA has been studying this quite heavily for the past 8 years, using the S-band and X-ban telemetry beacons on existing orbiters, etc...)
I know some of you may think this is BS....but both NASA and ESA have defined a serious future need for reliable communications on Mars....and MF/HF skywave comms is becoming their #1 choice!!
No BS here...
Since Mars is smaller than Earth, and "over-the-horizon" is closer than on Earth, and reliable / always available comms from one part of Mars to another part (even if just a couple dozen miles away) would require multiple "Martian geostationary" satellites and the Martian ground stations for TT&C...or they could use HF skywave communications!!
Since Mars has an ionosphere, MF/HF comms (such as NVIS) is becoming a viable #1 choice for reliable "over-the-horizon" comms, for most early human exploration (and early settlement) of Mars!!!
The Martian ionosphere is thinner than Earth's and is more sporadic in its variations (due to a lot of factors, not the least of which is Mars' thin overall atmosphere and weak magnetic filed), but interpolated data so far indicates that reliable comms can be assumed on the lower bands (such as 1mhz thru 10mhz) and using ALE (and/or SDR-ALE systems) may allow reliable HF skywave on most HF freqs, across the whole planet...
So....
So, even if the "iWave" isn't a big seller, future human explorers and settlers on Mars, will most probably be using HF "skywave" communications for their very lives!!!
Now, how's that for "future proof"???
Fair winds...
John
s/v Annie Laurie
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18-08-2014, 19:59
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#7
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Nearly an old salt
Join Date: Jun 2009
Location: Lefkas Marina ,Greece
Boat: Bavaria 36
Posts: 22,801
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Marine HF-DSC-SSB, the GMDSS, "communications stool legs"
John as for the satphone piece I was referring to your response to " Dan" on the SSCA discussion.
As to the future of DSC HF. I wouldn't be so sure. The increasing fitment of sat comms and especially with new LEO and GEO systems mean that this type of equipment will overtake and replace HF on commercial shipping. The fundamental need to have access to the Internet will drive all thinking that way.
Ultimately satcomms in all its forms can technically provide every SAR needs and more into the future.
Of course we will be using the " Ether " to send radio signals. But I suspect within a few years the concept of analog voice will be gone like the dodo bird or the rotary telephone. Ships at sea ( or space craft on mars ) will enjoy reliable high spied network data providing all sorts of communications. Faculties., some not thought of today.
Future gazing with today's technology is extremely unreliable, primarily because we can't predict things that arnt invented because if we could , they'd be invented ready !!!
PS. GMDSS did not remove trained radio operators, you still need in the vast majority of the world, to do various licenses to operate ship board radio equipment. What GMDSS eliminated was ( a) dedicated radio watch keeping and (b ) dedicated radio officers.
Dave
__________________
Interested in smart boat technology, networking and all things tech
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18-08-2014, 22:32
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#8
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Registered User
Join Date: May 2007
Location: Florida
Boat: Catalina 470
Posts: 2,595
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Re: Marine HF-DSC-SSB, the GMDSS, "communications stool legs"
Dave,
I think we may be talking past each other....my fault...sorry...
Perhaps its my rather tongue-in-cheek way of writing that is not translating well across the Atlantic???
I didn't mean to imply that radio operators aren't needed anymore....but rather that the average cruising sailor doesn't have to be a qualified "radioman" to use a DSC radio....
(perhaps my earlier wording was wrong / misconstrued....sorry about that!!)
Yes, I wish that everyone WOULD get the training....but fact is most sailors CAN learn how to do this in less than an hour!!!
That is if someone cares to inform them of how this stuff works, hoe robust/reliable it is, etc...(hey, now there's an idea!!)
I know that in most other "civilized" nations, LRC and GMDSS training is required....but not so over here on this side of the Atlantic....and these are the guys e-mail and asking questions....not the guys who are working as deck officers!!!
Whatever the case, I think you may be taking things as a "professional" (usually a good thing!), rather than looking at things through the lens of a cruising sailor on a budget, which are the ones e-mailing me and posting questions here....
???
I'm actually don't know for sure, but whatever I may have written that has given you the impression that I think "HF radio" is better than "satcom", please understand that is not what I'm writing/saying....rather I'm just trying to answer some questions sent to me and attempting to counter, the all-too-common notion, that "SSB' vs. "sat phone" is an "either" / "or" situation....
Heck, I've made my living in the satcom industry (and in the past 20 years specializing in commercial satcom)....and was one of the beta test users of Iridium before they signed up commercial customers (my brother was a senior Motorola eng (software, not RF) and he gave me a Iridium phone to use on shore and at sea...(I love Iridium, but a handheld sat phone is not now part of the GMDSS, nor is it likely to be part of it in the coming decade or so...and regardless of what new GMDSS systems SOLAS vessels will be using in the next 10 - 20 years, a handheld Irdium, or iSatPhone, sat phone is unlikely to be it..)
If you read the e-mails I get from folks with M-700's and M-710's (and even many with M-802's) who have no idea of how to use their radio (other than Sailmail), or those that haven't been able to get any response to their calls....or those that have been told by many well-meaning folks right here that all they need is a handheld sat phone, etc. and they're looking for some basic "context" to understand these systems with...
You may start to see where I'm coming from...
Like I write, this is for average cruising sailors on a budget, who might not be aware of what other "options" are viable...NOT for professionals in the industry....
I don't argue that satcom has come a LONG way and has significant inroads in commercial shipping....and I agree that this trend will continue...
But, that doesn't negate these main points here...
a) a cruising boat on a budget, heading offshore, can use many parts of the current GMDSS and not break their budget....
b) a 406mhz EPIRB, VHF-DSC-FM, NAVTEX, SART's, are all very affordable...
c) even a MF/HF-DSC-SSB is only a few hundred dollars more than a non-DSC HF-SSB....(and, MF/HF-DSC-SSB is not only part of the current GMDSS, but is still being used daily by commercial vessels at sea.....see the 2012 IMO/Jcomm survey for the details)
d) INMARSAT-C is relatively affordable...
e) A new FB500 is an excellent choice for hi-speed data / internet at sea, as it is poised to replace Fleet 77 on the GMDSS list....or an existing Fleet 77 will still give them years of excellent service...
f) and no where here can I foresee a handheld sat phone being part of the GMDSS....no matter what new satcom systems are coming down the pike (whether LEO or GEO)
Sorry....I won't ramble on and on about this any further....
The above was some clarification of my words and facts....
Below is just some fun / opinion...
As I wrote, we all have our opinions / biases / etc....and here I think we just need to agree-to-disagree....
Quote:
Originally Posted by goboatingnow
Of course we will be using the " Ether " to send radio signals. But I suspect within a few years the concept of analog voice will be gone like the dodo bird or the rotary telephone.
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Sorry about my comments about Mars....but since I doubt either of us will live long enough to see who is correct....I'm just going to smile when thinking of "dx'ing" on Mars...
Dave, I think you may want to just smile here, and get in on the joke!!
Quote:
Originally Posted by goboatingnow
Ships at sea ( or space craft on mars ) will enjoy reliable high spied network data providing all sorts of communications. Faculties., some not thought of today.
Future gazing with today's technology is extremely unreliable, primarily because we can't predict things that arnt invented because if we could , they'd be invented ready !!!
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Fair winds...
John
s/v Annie Laurie
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19-08-2014, 03:38
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#9
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Nearly an old salt
Join Date: Jun 2009
Location: Lefkas Marina ,Greece
Boat: Bavaria 36
Posts: 22,801
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Marine HF-DSC-SSB, the GMDSS, "communications stool legs"
John
GMDSS was never really designed with leisure vessels in mind. Hence your comments about relieving yachtsmen of requiring training is wide of the mark.
If anything GMDSS shows up that mandatory training in the US is really neccessary and I always shocked at the total lack of knowledge of GMDSS procedures and how rescues are organised. ( I don't mean the use of DSC , that's reasonably trivial in VHF, less so in HF )
I had the privilege of being trained under the watchful eye of a member of the original GMDSS panel. Leisure vessels never really entered his thinking. He was also passionate that the then RYA one day was not sufficiently deep to be compatible with other SRC Examinations , But that's another story.
Personally I think DSC is a horse designed by committee and there more nonsense in it than usefulness. It was like a cart pulled by two opposing horses , one the IMO commercial interests that wanted to remove dedicated radio watch keeping and hence radio officers and the SAR community that wanted simplified worldwide standardised altering to shore stations and not other nearby vessels
GMDSS represented a fundamental shift is rescue organisation, moving the responsibility under the old SOLAS conventions away from ships. People still feel that "shouting " to the nearest ship is a rescue system , under GMDSS it is not.
Personally I think the system is overly complex and the SAR aspects should not have got intermingled with other demands. A classic case is the nonsense of designated and non designated distress alerts for example.
Personally, in the case of a leisure yacht, which remains a non compulsory carriage vessel, I believe that whether you carry DSC HF /MF VHF or non DSC radio really makes little difference with the present situation, typically the yacht is supplemented by at least an EPIRB , and or multiple PLBs , then add sat phones, mobile phone ( near coasts ) , high seas Internet. Etc
There's no evidence that reasonably equipped yachts are suffering from SAR communications issues, whether they have DSC equipment or not. Hence I personally don't feel it's a do or die situation, voice only radio, along with more modern SAR alerting devices in my opinion , fall under the category of " will do "
I sail around coasts containing vast amounts of DSC equipped VHF and MF stations, yet I still almost never ever use DSC in routine conversations. AIS now gives me the ships name and this has been a boon to bridge to bridge conversations , most ships will respond to their ship being called on voice via its name.
In my opinion GMDSS training ( note GMDSS not radio ) should be mandatory in all GMDSS signatory countries. This should cover SAR alerting procedures , SAR organisation, the role of the MRCC on distress response organisation, the proper use and limitations of the various safety radio devices and other issues. The use of the actual radio is somewhat trivial
Ultimately DSC is going to be completely overtaken by digital voice technology, VoIP , meshed comms networks etc, the relentless push to digital will sweep all before it. ( look at the huge channel wastage in current VHF and MF/HF allocations ) .
In the long run our children will smile fondly at the notion of quaint radios that required " tuning " etc. Nearly all terrestrial radio is transitioning to digital or " pseudo - digital " systems, ultimately more advanced LEO systems combined with land based systems ( rather like the lite squared idea ) will dominate our communications future.
Why use clunky radios, when in the future you'll just push an icon on your personal digital smartphone/ wearable tech device. I can't see technology originating from the late 19th century surviving on similar format into the mid to late 21th
Dave
__________________
Interested in smart boat technology, networking and all things tech
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21-08-2014, 14:24
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#10
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Eternal Member
Join Date: Jul 2006
Posts: 4,046
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Re: Marine HF-DSC-SSB, the GMDSS, "communications stool legs"
Dave,
Good post! I agree with most of it, especially that HF/DSC and GMDSS was NEVER intended for the leisure sailor, i.e., yachtsman.
John and I agree on most things, and he is a knowledgeable and tireless champion of HF radio. His (extremely long) posts, while sometimes tedious and by his own admission, "over the top", are still very useful and valued.
However, we disagree on HF/DSC. We are in 180-degree opposition on this point.
John seems to believe that an older HF radio without DSC is worthless in the "new" GMDSS environment. I disagree 100%. That is pure poppycock. Both on the marine frequencies and the ham frequencies, HF voice is still active and extremely useful. Just ask the hundreds of active cruisers who are still using it every day (listen to the Cruiseheimers Net, the Waterway Net, the 14300 Maritime Mobile Net, WLO, etc., etc.).
HF voice is STILL an extremely valuable tool for the cruising sailor, with or without DSC.
I agree with you that GMDSS is a mess, a global system developed by lots of interested parties without a common optique and, worse, without practical knowledge and experience of maritime communications. I think it's not long for this world. Sooner or later, it will be trashed and surpassed by technological innovations and saner minds.
For those who don't agree, I'd advise you to watch all of John's videos on DSC on the Icom 802 and, for further clarification, read the 39 pages of instructions in the 802 manual on DSC operations. Do that severall times, and without imbibing while you're doing it.
Then, imagine how much of that you'll retain when -- six months from now -- you're knee-deep in seawater and needing assistance!
Bill
WA6CCA
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25-08-2014, 10:28
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#11
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Registered User
Join Date: May 2007
Location: Florida
Boat: Catalina 470
Posts: 2,595
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Re: Marine HF-DSC-SSB, the GMDSS, "communications stool legs"
Dave, Bill, et al,
Thanks for your learned opinions here...
It's always nice to hear from you both...
(Dave, as I wrote above, I think we are talking past each other....and looking at things from different angles, and we may in fact be in closer agreement than you think, except for your thinking that " The use of the actual radio is somewhat trivial"....maybe things are getting "lost in translation" but no worries mate!)
( Bill, despite my overt and strident promotion of MF/HF-DSC....I do agree that HF Voice comms DOES still have a very important place in most cruising / offshore voyaging, sorry I didn't make that clear.....so we are not that far each other on that point....
However, with many cruisers still thinking yelling mayday on 2182 is the way to signal distress.....my opinion is that there is no reason not to equip an offshore cruising boat with an MF/HF-DSC-SSB radio, and lots of reasons TO install an M-802, and learn how-to use it....again, just my opinion here!)
Due to the number of e-mails and PM's I've gotten, my intention in the SSCA posting was simply to inform many cruisers of what the GMDSS is, and how they may wish to take advantage of it....(and how not equipping with HF comms gear, AND learning how it works / how-to use it, but rather trying to "replace" HF comms with a handheld sat phone, has proven to be a mistake by many...)
Nobody here has ever written/implied that the GMDSS was intended for recreational boats, etc.
But, rather that since the GMDSS was implemented most shoreside voice radio watch, as well as most ship's voice radio watch requirements, have disappeared.....
And, the unfortunate fact that many cruisers are not aware of this, nor of what the GMDSS is, etc. (nor that there are hundreds of shore stations monitoring MF and HF DSC, etc.)...
We all may never fully agree on all of this...but, I think we can agree on a few points??? (I think, yes???)
a) Properly registered 406mhz EPIRB's are a good thing....
(note that I mentioned this first, right-up-front, in my posting)
EPIRB Activation? What happens/How to improve rescue odds
VHF-DSC is ubiquitous, but even today many don't have an MMSI#, nor a GPS position input to their VHF-DSC radio.....
Whether you think it useful / recommended / viable, or not....MF/HF-DSC is a very robust means of communicating/signaling...(even if it is a horse w/ 16 legs, it still gets the job done...
NAVTEX (and WeFax) are useful and reliable...
INMARSAT's GMDSS-certified satcom systems, INMARSAT-C, Fleet 77, etc. (and the soon-to-be GMDSS cert FB500) are all reliable means of sat comm...(although most cruising boats opt for a less expensive and/or more cost effective approach, these do work well...)
SART's have very small penetration into the cruising community, and few even know what they are....but some may wish to be informed....
This is what I wrote....and I stand by it 100%....
Quote:
Parts of the GMDSS system that most find easy/affordable/useful (all within easy reach / affordable parts of the GMDSS for cruising boats...):
--- 406mhz EPIRB's (relatively inexpensive at $400 - $700, and easy to "sell" to cruising sailors..)
--- Marine VHF-DSC-FM (cheap and almost ubiquitous now-a-days...anyone that doesn't have a Class D VHF-DSC, REALLY needs to spend the few hundred dollars now!!!)
--- Marine MF/HF-DSC-SSB (HF-DSC is a VERY robust/reliable means of signaling.....and with reasonable costs of ~ $1800 new, ~ $1000 used, for an Icom M-802 MF/HF-DSC-SSB Radiotelephone....and simple-to-use, robust and reliable...it is an easy "sell", almost a no-brainer!!)
--- NAVTEX (inexpensive and very useful for most coastal sailors and/or those plying the Med, etc., with typical forecasts for waters out to 150 - 200 miles....but in some areas the forecasts are only for the next 24 hours, so other weather sources, such as HF-WeFax are recommended...) (and in US waters, the VHF-based NOAA Weather Radio system is widely used, so NAVTEX hasn't caught on in the US, as it has in Europe and the Far East...)
- WeFax....And while HF WeFax was not adopted officially as part of the GMDSS, according to a 2012 survey by the Joint WMO/JComm group, HF comms, DSC, voice, and data are used daily by a majority of ocean going vessels, and HF wefax being reportedly used daily by > 85% of them....so, for offshore/hi-seas weather info/forecasts beyond the "text" weather info provided via INMARSAT-C and some HF coast stations, HF WeFax still rules as the predominate "1st choice" when offshore, even in 2012, even for large ships / SOLAS vessels....)
Parts of the GMDSS that are a bit more expensive:
--- INMARSAT-C,
While INMARSAT-C might seem to some to be a bit pricey, at ~ $3000 - $3500, is a VERY viable communications tool to have on-board long-range cruising boats...as it gives, thru its FREE "SafetyNet" service, offshore/hi-seas weather info/forecasts (in plain text), position reporting and weather reporting thru NOAA and AMVER, and Distress Signaling....ALL FOR FREE....
NO monthly/annual subscription, NO Fees at all, until/unless you use it to send regular e-mails, and then you're just billed by the character/letter....
(and it is very robust/reliable....many orders of magnitude better than a handheld sat phone!!)
--- INMARSAT Fleet systems (such as F77) are pricey at $15,000 - $20,000 and are big/heavy, and use significant amounts of electrical power....
So, here if cruiser's desire hi-speed data / broadband internet access / etc., Iridium Pilot or INMARSAT Fleet Broadband systems (at ~ $4500 - $5000) are usually the typical choices....
--- SART's (X-band radar Search And Rescue Transponders) are reasonably priced at $600 - $800.....but are often over looked by many cruising boats, as they figure a working EPIRB in their liferaft will do them better...
And, if deciding between a second 406mhz EPIRB and a SART, I'd choose the second EPIRB!!! (but, if you're cruising in heavily-trafficked areas, with poor visibility, such as UK/North Sea, etc. then a SART would be a GREAT idea, and I'd recommend one before a second EPIRB...)
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My intention was simply to inform many cruisers of what the GMDSS is, and how they may wish to take advantage of it....even if it is/was intended for commercial shipping, parts of the GMDSS are affordable and used by the cruising community, even if they aren't fully aware of what the GMDSS is...
(NOT to convince anyone to scrap their sat phones, not toss overboard their M-700's!!)
Whether, in the coming decades, all parts of the GMDSS survive in their current form or not, the fact is that it is still now currently a viable system for cruisers to be aware of....whether they choose to use any part of the GMDSS is their choice, but many are simply not aware of it...
HF Comms is still a viable tool for all long range cruisers/voyagers to have on-board.....(yes Bill, whether HF-DSC or not....)
Quote:
Originally Posted by btrayfors
John seems to believe that an older HF radio without DSC is worthless in the "new" GMDSS environment. I disagree 100%. That is pure poppycock. Both on the marine frequencies and the ham frequencies, HF voice is still active and extremely useful. Just ask the hundreds of active cruisers who are still using it every day (listen to the Cruiseheimers Net, the Waterway Net, the 14300 Maritime Mobile Net, WLO, etc., etc.).
HF voice is STILL an extremely valuable tool for the cruising sailor, with or without DSC.
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But, if they are not regular radio users, and/or not hams, and/or not cruising within range of a "cruiser's net" when they need communications, etc. then HF-DSC signaling can be a rather fool-proof addition...
I know that a few years ago (even with my years of experience), I had difficulty raising WLO from the middle of the eastern N. Atlantic on HF Voice...but I sent them an HF-DSC call, got a quick response and was talking with them in less than one minute....(they remarked that my signal was good, but that they "just didn't hear me when I was calling"....
Again, I was not saying that any radio that isn't MF/HF-DSC equipped is useless.....but just that, in my opinion, not equipping with a MF/HF-DSC radio is short-sided....(again, just my opinion!!)
Perhaps my personal crusade on behalf of MF/HF-DSC has seeped thru my words???
For that I apologize...
But, I still stand behind the words I wrote above...
A "horse designed by committee"....yeah, probably....but that doesn't discount that it works...
And, since the M-802 is the only affordable MF/HF-DSC-SSB radio available, it makes sense to me that those deciding on a communications plan for their cruising boat be aware of what MF/HF-DSC is, how it works, and especially how the M-802 works....
(whether you think the "horse" has 16 legs and walks with a limp or not....she still gets the job done....and for the time being, it is what we've got...)
I do not have the advantage of academia / original GMDSS panel, but rather have the disadvantage of having to deal with what we've got in front of us right now and for the next decade....and with many sailors/cruiser's being uninformed of the GMDSS, HF-DSC, the M-802, etc. what's been in front of us now for the past few years hasn't been too pretty....but, the good news is that (in my opinion) it's getting better...
Regardless I will not argue this point....as it is rather moot to the main point here, which is that simple education / training is important!!
Regarding Distress signaling / SAR communications, I think this is the one area where Dave and I disagree....but I suppose this might depend on what the definition of "reasonably equipped" is...
Quote:
Originally Posted by goboatingnow
There's no evidence that reasonably equipped yachts are suffering from SAR communications issues, whether they have DSC equipment or not. Hence I personally don't feel it's a do or die situation, voice only radio, along with more modern SAR alerting devices in my opinion , fall under the category of " will do "
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I have personally read multiple stories (some in "Cruising World", some right here on Cruiser's Forum, some from sister ships of mine, some from other cruisers, etc.) of sailors / cruisers who HAVE had difficulty in "SAR communications" when attempting various means of contact....
While all that activate a properly registered EPIRB have found few issues, many found handheld sat phone to be of little use / effectiveness (a few never got connected), and those that attempted to signal via 2182 (I believe all non-hams or new hams) also failed to have success...
Now, I don't have the names/dates available off-the-top-of-my-head (I'm working out-of-town at the moment), but here I think we see how my experience and knowledge of those who have had "SAR communications issues", shapes my view/opinion...
Please understand that I'm NOT saying that Dave is wrong, and I'm right...
Just that we have different views/opinions on this point....and I suspect due to our different experiences, etc. not because one or the other is "wrong"....
This is not really what the point of the thread was, but thought you may wish to read of how things are in S. Florida / Bahamas these days....
Dave, it is getting better....but, how I wish this was the case over here!!!
Quote:
Originally Posted by goboatingnow
I sail around coasts containing vast amounts of DSC equipped VHF and MF stations, yet I still almost never ever use DSC in routine conversations. AIS now gives me the ships name and this has been a boon to bridge to bridge conversations , most ships will respond to their ship being called on voice via its name.
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As recent as 2 weeks ago, along the SE coast of Florida I hailed a commercial vessel, who was transmitting a Class A AIS signal, I started calling them at a range of about 12 miles....after 5 attempts on VHF ch. 16 and 13, and no response...I sent him a VHF-DSC call and he responded in about 30 seconds and we spoke on VHF ch. 13 straight away....
And offshore, just a while back I needed to call a vessel on 2187.5 DSC to get them to respond....
Again, not really what this thread is about, but thought maybe this would show how different things are over here....
I hope those reading all of this don't turn away thinking that there is just too much arguing!!!
My hope is that those reading this will read my SSCA posting and watch that old GMDSS video, and further educate themselves on communications ideas/options, including the GMDSS...
And, that is the main purpose of the posting....encouraging folks to educate themselves!!
Fair winds to all..
John
s/v Annie Laurie
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29-07-2018, 13:58
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#12
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Registered User
Join Date: May 2007
Location: Florida
Boat: Catalina 470
Posts: 2,595
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Re: Marine HF-DSC-SSB, the GMDSS, "communications stool legs"
While there haven't been many changes to the GMDSS....there are a few....like Iridium's new offering from their "NEXT" satellites (Certus) awaiting GMDSS certification, and INMARSAT's Fleet Broadband waiting on the same.....
But, with the prices of those systems and airtime/data costs, it's unlikely any of my fellow budget-conscience cruisers will be ordering any of those anytime soon!!
So...
So, what to do??
Well, there are of course parts of the GMDSS that we all use daily, and many other parts that we equip our boats with....and while the GMDSS was designed to work without specially-trained personnel, it is good to know something about radios, radiowave propagation, etc....
So, that's why I made all the videos that I did...
This fall, it will be a few years since I recorded/uploaded these videos...
And, while neither the radio nor the basic approach to using it has changed, what has changed is the ~ 11yr solar cycle (which regulates the foibles of long-range radio communication)....
As you can see from this graph, when I recorded most of these videos in Oct 2013 (and again in early 2015), the sunspot cycle wasn't great (avg SSN of 55 to 60), it was much higher than today, in 2018...
So...
So, this month (July 2018) I did another video, updating and describing current HF radiowave propagation for the offshore mariner (whether they use maritime or ham bands)...
This new video, together with my earlier video regarding channel / frequency choice and the basics of Radiowave Propagation, should give many of you some assistance in getting the most out of your HF communications system on-board.
I've posted it to Youtube, and have also added it to my Youtube Playlists so as to be available to all....
Please have a look:
https://www.youtube.com/playlist?list=PLnN6ygtZ3h2npivDjoFrC-8QKVyMb4tVr
Maritime HF Communications
https://www.youtube.com/playlist?list=PLnN6ygtZ3h2nPNdApNsZDo_Jk3NB_Bt1y
And, I added it to the beginning of the Playlists above, and to the end of these two Playlists, below:
HF-DSC Communications
https://www.youtube.com/playlist?list=PLnN6ygtZ3h2n3z5nlv-ga2zYuPozhUXZX
Offshore Weather
https://www.youtube.com/playlist?list=PLnN6ygtZ3h2mPZAx2vWzdjTJjHlChruyY
Please have a look at these Playlists.....they should help many of you.
Fair winds.
John
P.S. FYI, here is my original video regarding channel / frequency choice and the basics of Radiowave Propagation, from Oct 2013...
__________________
John, KA4WJA
s/v Annie Laurie, WDB6927
MMSI# 366933110
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03-09-2018, 14:58
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#13
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Registered User
Join Date: May 2007
Location: Florida
Boat: Catalina 470
Posts: 2,595
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Re: Marine HF-DSC-SSB, the GMDSS, "communications stool legs"
Hello to all,
I just recently uploaded a couple new videos, showing LIVE, real-world Ship-to-Ship HF-DSC calls...
I've added them to my HF-DSC Playlist...please have a look....(and, please watch the playlist in order, so that it all will make sense)
https://www.youtube.com/playlist?list=PLnN6ygtZ3h2n3z5nlv-ga2zYuPozhUXZX
And, for those completely familiar with their radio and with HF-DSC, here are the videos:
"Live, Ship-to-Ship HF-DSC Calling, on GMDSS HF-DSC Calling Freqs"
__________________
John, KA4WJA
s/v Annie Laurie, WDB6927
MMSI# 366933110
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28-07-2020, 12:29
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#14
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Registered User
Join Date: May 2007
Location: Florida
Boat: Catalina 470
Posts: 2,595
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Re: Marine HF-DSC-SSB, the GMDSS, "communications stool legs"
Hello to all,
Once again I'd like to add some clarifying information.
Due to my efforts to promote HF-DSC, I unfortunately went too far and inadvertently caused some confusion....please ignore and forget my comments specifically dealing with "routine" HF-DSC signaling (you can skip that video, as well), unless you have some unique/specific need to investigate / learn about "routine" signaling....
Please just stick with the "Distress" (MayDay) signaling and "Safety" (Securite`) signaling (for weather, navigation, communications testing).
Those of us on private yachts, with the Icom M-802, etc., will mostly be using MF/HF-DSC for "Distress" signaling (MayDay) or "Safety" signaling (for weather, navigation / communications testing, etc.)....and that's probably it...
And, you're going to be using one of the six Int'l GMDSS DSC "Safety" / "Calling" frequencies
[2187.5khz; 4207.5khz; 6312.0khz; 8414.5khz; 12577.0khz; 16804.5khz]
Although, I already mentioned that the USCG offers "automated DSC Testing" on 4207.5khz, from 3 of their locations, if you are beyond 4mhz comms range, they do accept DSC "Safety" calls for testing / verifying proper HF-DSC system operation, as long as you don't do this often (typically once per year / once per season, or only prior to an ocean passage).
Some additional supporting info for this:
From US FCC Part 80 Rules & Regs (Maritime Mobile Service):
80.359 Frequencies for digital selective calling (DSC).
(b) Distress and safety calling. The frequencies 2187.5 kHz, 4207.5 kHz, 6312.0 kHz, 8414.5 kHz, 12577.0 kHz, 16804.5 kHz and 156.525 MHz may be used for DSC by coast and ship stations on a simplex basis for distress and safety purposes, and may also be used for routine ship-to-ship communications provided that priority is accorded to distress and safety communications. The provisions and procedures for distress and safety calling are contained in ITU-R M.541-9 (incorporated by reference, see § 80.7), and § 80.103(c).
And, some further info (primarily dealing with the equipment and crew familiarity):
Quote from US Gov't Pub 117:
Use of GMDSS Equipment for Routine Telecommunications; GMDSS telecommunications equipment should not be reserved for emergency use only.
The IMO has issued COMSAR/Circ.17 (dated 9 March 1998) which recommends and encourages mariners to use that equipment for routine as well as safety telecommunications. The following recommendation is extracted from Circ.17:
Use of GMDSS equipment for transmission of general radiocommunications is one of the functional requirements specified in SOLAS chapter IV, regulation 4.
Regular use of GMDSS equipment helps to develop operator competency and ensure equipment availability. If ships use other radio communication systems for the bulk of their business communications, they should adopt a regular program of sending selected traffic or test messages via GMDSS equipment to ensure operator competency and equipment availability and to help reduce the incidence of false alerts.
This policy extends to all GMDSS equipment suites including Digital Selective Calling (DSC) on VHF, MF and HF, to the Inmarsat systems, and to any duplicated VHF and long-range communications facilities.
{Over the years, I've attempted to be a bit less USA-centric, trying to point to the international uses of the GMDSS.....and I've mentioned some sailors recommendations for using MF/HF-DSC in ocean rallies, etc., as well as encouraging the use of "regional MMSI's" for regional-group calling... but these are rather specialized / niche uses, and I now realize that those interested in them will either already be aware or will be smart enough to ask/learn....so, no need for me to be rambling on about them... }
Without going into the weeds of the original GMDSS plan, nor specifically Digital Selective Calling (DSC), please remember that this system was originally designed/planned in the late 1980's / early 1990's, and implemented starting in 1992....so, much has changed....not the least of which most "public correspondence" (ship-to-shore phone calls) is handled via sat comm, as are most "data comms" that aren't being handled privately via PACTOR....
While the MF/HF-DSC system (as well as the VHF-DSC system) is an integral part of the GMDSS (Global Maritime Distress and Safety System), the main use these days is the "Distress" signaling and "Safety" signaling, not the "Routine" signaling that was intended to be used for both ship-to-shore and shore-to-ship signaling, by both "public coast stations" (for "public correspondence" and ship's/fleet's business) and "private coast stations" (usually for ship's/fleet's business, using SITOR/FSK)...
So, while we can continue to rely on the GMDSS to be there when we need it [406mhz EPIRB's; NAVTEX; VHF-DSC-FM; MF/HF-DSC-SSB; SafetyNET broadcasts; INMARSAT-C (and now / soon-to-be INMARSAT FB and Iridium Certus); SART's (AIS-SART's or SART-X's)], we should remember (or rather I should accept?) that most sailors/cruisers (except those using NAVTEX...mostly in Europe or Asia), these days only use the GMDSS in times of "Distress"....so...
So, perhaps we could learn something from the IMO (International Maritime Organization) that started the whole SOLAS (Safety-Of-Life-At-Sea) idea, and came up with the GMDSS in the first place?
Maybe we should heed their advice?
Have a look again at what their advice / recommendations are:
Use of GMDSS equipment for transmission of general radiocommunications is one of the functional requirements specified in SOLAS chapter IV, regulation 4.
Regular use of GMDSS equipment helps to develop operator competency and ensure equipment availability. If ships use other radio communication systems for the bulk of their business communications, they should adopt a regular program of sending selected traffic or test messages via GMDSS equipment to ensure operator competency and equipment availability and to help reduce the incidence of false alerts.
This policy extends to all GMDSS equipment suites including Digital Selective Calling (DSC) on VHF, MF and HF, to the Inmarsat systems, and to any duplicated VHF and long-range communications facilities.
Perhaps this is simply what I should have recommended from the beginning, some ~ 17 years ago, when I first started touting "HF-DSC"? But, whatever the case, that's what I recommending today!
I do hope this info is helpful to you all.
Fair winds.
John
P.S. Don't forget the "stickies" here, on Maritime HF Comms
Marine SSB Stuff (how-to better use / properly-install SSB, & troubleshoot RFI, etc.)
https://www.cruisersforum.com/forums/f13/marine-ssb-stuff-how-to-better-use-properly-install-ssb-and-troubleshoot-rfi-etc-133496.html
HF-SSB Radio, Proper Installation Tips/Techniques, etc.
https://www.cruisersforum.com/forums...tc-198305.html
And, for those looking for the easy-peasy link to a free video series / Playlists, have a look here:
HF-DSC Comms
https://www.youtube.com/playlist?list=PLnN6ygtZ3h2n3z5nlv-ga2zYuPozhUXZX
VHF-DSC Comms
https://www.youtube.com/playlist?list=PLnN6ygtZ3h2m-IejYg7J6QugtO2epizxF
Generic Maritime HF comms
https://www.youtube.com/playlist?list=PLnN6ygtZ3h2nPNdApNsZDo_Jk3NB_Bt1y
Offshore Weather
https://www.youtube.com/playlist?list=PLnN6ygtZ3h2mPZAx2vWzdjTJjHlChruyY
Icom M-802 Instruction Videos
https://www.youtube.com/playlist?list=PLnN6ygtZ3h2npivDjoFrC-8QKVyMb4tVr
Offshore Sailing
https://www.youtube.com/playlist?list=PLnN6ygtZ3h2nbwAGh5DKgTCj15iyl6qoY
__________________
John, KA4WJA
s/v Annie Laurie, WDB6927
MMSI# 366933110
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28-07-2020, 13:29
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#15
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Registered User
Join Date: Aug 2009
Location: between the devil and the deep blue sea
Boat: a sailing boat
Posts: 20,969
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Re: Marine HF-DSC-SSB, the GMDSS, "communications stool legs"
Quote:
Originally Posted by ka4wja
It is surprising that nobody has replied/commented here, yet...
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Because most people use sat phones?
b.
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