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Old 02-04-2015, 04:21   #46
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Re: Is an SSB/pactor modem worth it?

Quote:
Originally Posted by belizesailor View Post
And fortunately for them he also had a plan C...the EPIRB. Surprising how often plans A & B fail a aboard boats...best to think at least one more step beyond.
Yes, but the point was that he didn't actually have either Plans A or B. It's good to study this case, because we are probably all subject to the same failure mode.

If you have only one Plan, then you are more likely to think about it and be sure it works. When you think you have redundancy, it is only natural that you will relax a little. Eric relaxed far too much -- the only redundancy he had was redundant failure.

I am all for redundancy -- of course. But you have to fight this tendency to be lulled into complacency just because it appears superficially that you have redundant something. Getting back to the original topic -- SSB radio is not "plug and play". It requires knowledge and skill to use. Besides that, the installation is complicated, and you need to understand something about that as well, in case something goes wrong. SSB radio is not any good if you don't use it regularly. You can't just dust it off, as Eric did, and expect it -- and you -- to function effectively. So I do really think that SSB radio is not for everyone -- I think you need to have some interest in it, and some enjoyment in using it, in other words, at least a little bit of radio-nerdness, for this to be a really effective tool.

EPIRB does not back up all of the functions of SSB and sat phone, which are both two-way comms. You cannot use the EPIRB to get urgently needed medical advice, for example.
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Old 06-04-2015, 08:42   #47
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Re: Is an SSB/pactor modem worth it?

I think the answer to the original question of "is SSB/pactor modem worth it?", has been answered with a consensus that yes "SSB" radio is worth it, for sure....but that a PACTOR modem is a pricey bit of kit that might not be worth it for some/many (even those who already bought one!)...

And, I usually agree with Dockhead (or on issues I have little experience with, defer to his experience)....but here I disagree with 'ya, well disagree with 'ya a little bit anyway...
FACT is that using MF/HF-DSC-SSB Radiotelephones for Distress Signaling is VERY EASY, and VERY RELIABLE, and provide excellent results....
BUT...
But, s/v Rebel Heart didn't have an MF/HF-DSC Radio (heck he even refused to hook-up a GPS to his VHF-DSC radio and commented that "nobody even knows what that DSC stuff is, let alone uses it."!!), and THAT is my point here....and this is why I disagree with Dockhead and others who wish to use s/v Rebel Heart as an example of how hard it is to use an SSB radio in an emergency....
Yes, in the Rebel Heart incident it WAS....but that was an old/used Non-DSC SSB radio (and a woefully ignorant operator, who took a good deal of bad/old advice), and few seem to point this out!!
Using an MF/HF-DSC-SSB-Radiotelephone for emergency signaling is as easy as pressing one button!


While we all know that he didn't really have effective plans, whether a Plan A or a Plan B, the "teachable moment" here is that HE thought he had both!!
And, while I agree that human nature might say that if you have only one plan, you may be more likely to make sure it works 100%, than if you have a Plan A, Plan, and even a Plan C....
I think if any ocean sailor is planning on having a emergency plan or plans (some choose not to, and I will not quibble with them, as it is their choice), then they should make sure each one works as close to 100% as possible, or why even bother!!!


As I've politely written about previously, Eric's (s/v Rebel Heart) Plan A (handheld sat phone) wasn't well thought-out, nor even properly implemented to his own fairly lax standard...
But, it was his Plan B (Marine SSB) that was not only poorly thought-out, it was seriously flawed....
--- both his choice of a non-DSC radio AND,

--- his complete lack of familiarity with not only his own radio,
--- complete lack of knowledge of what channels/freqs to actually use (not 2182!),
--- and total lack of knowledge of how to choose the correct channel/freq based on time-of-day / distance to communicate!!

He simply took advice from both "other cruisers" in California and those selling old/used SSB radios, both of whom appealed to his low budget approach and many ironically eschewed the "old fashioned tech" [sic] of "SSB" in favor of an expensive sat phone, except for using the SSB radio for Mexican "cruising nets"???
And the few (myself, at least) that mentioned HF-DSC and the GMDSS (which has not just revolutionized how calling/signaling is done on Marine HF Radio, i.e. "Marine SSB", but also significantly improved responses to calls for assistance), seem to have been ignored!

Since the implementation of the GMDSS in 1992 (23 years ago!) and its mandatory requirements for all SOLAS vessels and all signatory nations, in Jan 1999 (16 years ago!), actual operator use of "SSB" to raise someone in an emergency / urgency has become pretty easy-peasy due to the requirement of using MF/HF-DSC rather than Voice SSB....

Quote:
Originally Posted by Dockhead View Post
Yes, but the point was that he didn't actually have either Plans A or B. It's good to study this case, because we are probably all subject to the same failure mode.

If you have only one Plan, then you are more likely to think about it and be sure it works. When you think you have redundancy, it is only natural that you will relax a little. Eric relaxed far too much -- the only redundancy he had was redundant failure.
See some specifics here in red...

Quote:
Originally Posted by Dockhead View Post
Back t
Quote:
Originally Posted by Dockhead View Post
o the original topic -- SSB radio is not "plug and play". It requires knowledge and skill to use.
Not if you're referring to MF/HF-DSC Distress signaling, which takes little to no knowledge/skill, and IS "plug-'n-play"!!!

Besides that, the installation is complicated, and you need to understand something about that as well, in case something goes wrong.
Again, not really any more complicated than NMEA wiring, or networking instruments / MFD, etc...
And, if done correctly from the start, most marine SSB installs last decades with little maintenance required....

SSB radio is not any good if you don't use it regularly. You can't just dust it off, as Eric did, and expect it -- and you -- to function effectively.
While for optimal use / performance, yes regular use is important...
And, surprisingly to some, the GMDSS rules/regs specifically recommend that vessels use their GMDSS equipment, including MF/HF-DSC, regularly and for routine signaling, in order to maintain proficiency in operations!!

So I do really think that SSB radio is not for everyone -- I think you need to have some interest in it, and some enjoyment in using it, in other words, at least a little bit of radio-nerdness, for this to be a really effective tool.
Here, I disagree with you...
Sorry, just my opinion.....but I think with modern radios (M-802, FS-1575, etc.) and spending a few minutes watching a few videos, and a few more minutes reading, ANY sailor/cruiser can very effectively use a MF/HF-DSC Radio!!


If you take a look at what I wrote about 6 months ago, you'll see that not only was I posting about these matters for years now, but that there was an eerily foreshadowing of the s/v Rebel Heart incident, published almost TWO YEARS BEFORE s/v Rebel Heart departed on their doomed voyage!
Quote:
Originally Posted by ka4wja View Post
....A rather eerily foreshadowing of the s./v Rebel Heart incident....
--- A REAL interesting thing to me was this Noonsite article from June 2012....
The Essential Role of HF/SSB Radio in Ocean Cruising €” Noonsite


Although it was the first 2 sentences that originally caught my attention...
Quote:
"As the operator of the SailMail station that covers SE Asia, the NW Pacific and eastern/northern Indian Oceans, from here in Brunei (NW coast of Borneo), I am often surprised that so many international cruising yachts coming into this region do not have a proper [DSC-equipped] marine HF/SSB radio.
Talking with yacht owners, it seems that information is not available to them regarding the importance of marine HF/SSB with DSC in the Pacific and Indian Oceans, SE Asia and Australia/New Zealand."
It is actually his eerily foreshadowing of the s/v Rebel Heart tragedy / debacle, that made me sit up and take full notice, and makes me wonder!!
Quote:
..."Other cruisers may be mislead by what might seem to be an easy solution - just buy a satellite phone. The satellite phone salesman will get a good commission on the equipment sale and the ongoing connection time payments. The HF radio salesman will sell you the radio, but all voice communications to other yachts, coast stations, MRCCs etc is free after that. So too, is listening to broadcast weather forecasts, world news and receiving weather faxes. Nothing is free with the satellite phone.
If the satellite phone runs out of credit in an emergency or distress situation, communication stops. Not so the HF/SSB [DSC] radio, you can call MRCCs, other yachts, ships etc without fear of running out of credit or creating a massive post-paid bill. Cruisers can therefore play their part in the international network of vessels at sea listening for distress or emergency communications and be one of the available vessels that can help; just like cruisers would like someone to help them if they faced a serious problem. A DSC equipped HF/SSB radio is a great advantage in this role.
...One reason for DSC in marine HF/SSB radios is to reduce an aspect of uncertainty with any radio comms; "have I called on the right frequency/channel and is the intended recipient's radio turned on?"
Please remember this article was written / published almost 2 years BEFORE the s/v Rebel Heart incident!!



Although initial contact is done via MF/HF-DSC...this is what we are all talking about when talking about "Marine SSB" these days...



The bottom line here in discussions about "Marine SSB" / "HF Radio", is that we should all try to use "HF-DSC-SSB" rather than just "SSB"....
But, that's going to be a hard thing to accomplish....so, I came up with a possible solution, and that is to simply remind everyone that when we are talking about "SSB", we ARE actually referring to "MF/HF-DSC-SSB-Radiotelephones"....
Although even this is difficult to do, but at least I'm trying!

Those that wish to still tout the fact that "any old radio will work", should understand that while this might work in US coastal waters, or even in heavily-cruiser-populated areas where you cannot throw a baseball and not hit another cruising boat, the FACT is, that when heading offshore, and/or to remote locales, and/or across oceans, etc. an old, non-DSC radio (or even a new "ham radio") is NOT a viable option / plan for emergency signaling or even to raise shore stations or other vessels....
Remember, there are > 450 Coast Stations worldwide that monitor MF-DSC, and > 80 Coast Stations worldwide that monitor HF-DSC, and literally 1000's of ocean-going vessels and SOLAS-grade vessels worldwide that are also monitoring MF/HF-DSC!!!
But, except for SOME HF Voice freqs that the USCG, and Australia and NZ Maritime Authorities monitor, NOBODY else is listening/monitoring/watch-standing on HF Voice anymore!! (and haven't been for > 15 years now!)

{Yes, I agree that if you do NOT have a MF/HF-DSC Radio, there still are options....such as hailing USCG, AMSA, NZMA, etc. on some of the intn'l GMDSS Voice freqs, or calling on 14.300mhz ham radio (assuming 20m is open/usable at the time)....but these are "options" not real "plans"....and of course these options require you to know about the radio, radiowave propagation, etc....}

Of course, a properly registered and tested EPIRB is going to be a good "one-way" emergency signaling device...have a look here for details that you might be surprised by...

EPIRB Activation? What happens/How to improve rescue odds



My main point here is that when I, and others, write about "SSB" / "Marine SSB", we are talking about "MF/HF-DSC-SSB-Radiotelephones", which is a FAR CRY for the old/used non-DSC radios or even new "ham radios"....
And usually, when discussing whether one is "worth it" or not, we usually are incorporating the "DSC" feature into this advice/recommendation....
But, since the original poster has not returned here to give more details on their planned cruise, etc. and they did mention looking for used radios on ebay, etc. for about $1000, AND they seemed to describe their use as "getting weather" (and e-mail) when away from cellular/Wi-Fi, I assume they (like many) were unaware of HF-DSC....so, not sure if they were contemplating installing an MF/HF-DSC-SSB Radiotelephone, or not???


I know this rambling was a bit off-topic from the original one, but I do hop it helps some...
For EASY, real-world explanations and live, real-world demonstrations, and even more info on HF-DSC, have a look here...

https://www.youtube.com/playlist?lis...ga2zYuPozhUXZX

New HF-DSC Explanation and LIVE Demonstration Videos


Fair winds..

John
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Old 06-04-2015, 09:14   #48
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Re: Is an SSB/pactor modem worth it?

John,
With marine HF SSB DSC still being "just" HF SSB...before I get too happy about that concept, how's it going to work for range? I know, on paper, five watts can go around the world. But now the signal is digital and it must arrive somewhere, in good enough condition to be acted upon. So, considering frequency, propagation, weather, and all the real-world reasons why HF digital transmissions can fail to arrive...


How much is HF DSC going to depend on "Am I in the shipping lanes?" and other real-world range limits?


And then of course, since so many commercial vessels ignore watch-keeping regulations anyhow...Just how many undercrewed freighters actually are keeping their HF DSC equipment on, with a communications watch actually staying within earshot of the speaker? I've seen a small cruise ship on autopilot with NO ONE at all in the bridge, and I'm not the only one. If there's no one there--the DSC is "off" whether it is on or off. If there's a stored message that no one sees until the next morning...I'm not sure they'd want to admit that, either.


I'm not knocking SSB and DSC here, just want a clearer context.
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Old 06-04-2015, 09:16   #49
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Re: Is an SSB/pactor modem worth it?

I would like to thread a middle ground here, with an alternate perspective. As background, I should note that I worked for several decades as an electrical engineer specializing in digital communications and helped design multiple communications standards.

Yes, KA4WJA, people should be experts in all the equipment they have aboard, particularly critical safety equipment. However, many modern cruising boats have multiple, highly-complex systems. One could argue about how critical they are, but reasonable arguments could be made that many systems (steering, navigation, fresh water, auxiliary propulsion, weather information, ground tackle, COB recovery) are more important than long range communication. Realistically, there are only so many systems that a vessel's master can be expected to master. SSB/HF/DSC technology has failed, in that regard, to provide intuitive and reliable communications to those who have only minimal experience with the systems. A billion people around the world can pickup a cellular phone and use it without extensive training. Newer satphone devices offer similar user experiences.

Perhaps the sales volume is too small to justify the investment, but in an ideal world, HF/SSB communications systems would have automatic built-in diagnostics and self-check, and would require no greater expertise to operate than that possessed by the average 7 year old child.

HF/SSB, particularly with DSC, is a powerful tool, and one that cruisers who find themselves offshore or far from other terrestrial forms of communication should be familiar with. The equipment and systems designers, though, have done a great disservice to the technology by not making it easy enough for someone's child or grandmother to use.

KA4WJA, you have made some excellent videos demonstrating the use of HF DSC. That these important videos were made, and are needed, is evidence that the technology is inadequate.

I'm not advocating that everyone toss out their SSB, only that people consider that there are many factors influencing a technology's use and adoption (and usefulness).
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Old 06-04-2015, 09:19   #50
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Re: Is an SSB/pactor modem worth it?

HF-DSC range is actually BETTER than SSB Voice!!
And, no need to be "near" other vessels or Coast Stations!!

I'm busy with some family at the moment....stealing away a few minutes on the keyboard...but, I will be happy to explain matters in great detail later!
Quote:
Originally Posted by hellosailor View Post
I'm not knocking SSB and DSC here, just want a clearer context.
But, 'til then, please have a look at these videos...

https://www.youtube.com/playlist?lis...ga2zYuPozhUXZX

Fair winds..

John
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Old 06-04-2015, 12:16   #51
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Re: Is an SSB/pactor modem worth it?

accomplice,
Just saw your posting...

And, while I respect your views and agree that your opinion seems valid, I hope you don't mind if I politely disagree with you a bit??
(although this may seem like I'm playing with semantics, I'm not!



I'll purposely delineate my opinions, from fact, here...
First a few facts...(but, forgive the generalizations I might make for layperson clarity of this posting)

a) HF-DSC is SITOR-B signal...which is Frequency-Shift-Keyed Radio-Tele-Type (FSK-RTTY)....
(and although our maritime HF-DSC uses the "modern" 1970's ASCII code, rather than the "old" 1930's Baudot code, FSK-RTTY has been around a lot longer than I've been alive!!)

b) HF-DSC, being a 100-baud FSK signal in a narrow 400hz bandwidth, is a very robust communications mode...
And, this "technically" gives it a significant advantage over SSB Voice in both range and reliability, and robustness...which, in the real-world is still a big advantage of 12 - 15db, sort of like having an SSB radio with 3000 - 4000 watts of power sending out your signal! (again, forgive the generality)

c) It was my non-technical sister (in her mid 60's, but has some tech understanding), who I was explaining HF-DSC to last year....
And, when I told her to think of it as a "Text Message" that doesn't use a cellphone, she understood what I was talking about immediately, and said "why don't you say that in a video!"
So, that is what I did!!

d) It was some friends sailing sisterships to my Annie Laurie, that asked me to send 'em some of my offshore sailing videos....but after spending quite some time sending BIG attachments, one of them just suggested I post 'em on Youtube....
So, I did that....and then I did the M-802 instruction videos, etc...
And, now I've done the HF-DSC videos, etc....



Those being facts, I think you may see now where I'm going to base some of my opinions on...

Some opinions...

e) This is not new technology at all, and has been used quite extensively over many decades and has been widely accepted by both maritime commercial operators as well as others...
So, in my opinion, the technology has NOT failed as you write ("SSB/HF/DSC technology has failed"), but rather is us, the sailing/cruising community that has failed to educate ourselves, and understand and adopt the changes that were happening for many years!!


f) I have been explaining and attempting to educate fellow sailors regarding DSC (and sometimes making a fool of myself, by touting its virtues) since 2001....and have been using HF-DSC myself on my current boat for > 11 years now...
Being that the intn'l DSC standards were set and implemented in 1992 (23 years ago) and MF/HF-DSC became mandatory for all signatory nations and all SOLAS vessels in Jan 1999 (16 years ago), and I've been explaining and promoting it since 2001 (14 years ago), and I've been actively using it on my own 47' sloop now for > 11 years....
In my opinion, the technology has NOT failed us....rather we have failed it!!


g) When just a few years ago (Nov 2010 or 2011, I think?), a glossy sailing magazine (CW) publishes a multi-page feature article (promoted on the front cover as the lead article) about a serious injury at sea on the return from the Bermuda Race, and the subsequent rescue, and allows the author to mention calling on 2182, during the middle of the day, from half-way between Bermuda and Rhode Island, and NEVER mention that while the USCG might have been monitoring that freq at the time (which the NO LONGER DO), there was no change of raising them on that freq at that time of day, from that location!!
But, even worse....the author never mentioned, and the editors never corrected his omission, that NOBODY ELSE was monitoring 2182 either!!! So, NOBODY was ever going to hear is MayDay call...
And, if that wasn't enough of a kick in the teeth to the GMDSS.....the editors went out of their way to write a 'sidebar" to the article, explaining that you should program the USCG phone numbers into your Iridium (or Globalstar) handheld sat phone, as that was the only way to signal for help....(except for an EPIRB, when you wish to abandon your boat)....
Now, remember this was more than a decade AFTER the full implementation (and SOLAS requirements) of the GMDSS, and this was the widest circulated "Cruising" magazine in the US (world?)....
And, to top that off....I wrote to them, a rather scathing letter-to-the-editor (e-mail), that went unresponded-to and unpublished....(the basically ignored their duties as journalists and sailors!)

Heck, even this past year....it took me a couple months and had to basically submit m CV to Practical Sailor, just to get them to realize some of what they were writing was old, tired, nonsense....(I'm not sure they ever even bothered to read the IMO and GMDSS docs I sent 'em...)

So, here I am, with my opinion that the technology of DSC, particularly HF-DSC has NOT failed us at all....but that WE, the cruising community have failed!!
And, it is up to us to fix our issues, educate ourselves, help each, and allow everyone to make decisions for themselves, based on the FACTS, not just the opinions of ignorant journalists or slick salesmen....no matter how nice or well-intentioned they may be...



And, finally....
I'm a passionate guy, who has a LOT of fun in life...but I tend to remember that old saying (from Mark Twain??), "show me a man that knows what's funny, and I'll show one that knows what's not."
Problem is that a smile and a knowing glance don't translate to a keyboard/screen!!

So, please take this with a smile!!
I know I want to know everything about everything....but understand I cannot know it all....and realize that others cannot either...
And, THIS is where HF-DSC helps!!
If a sailor spends a few minutes watching a video, and a few minutes reading (the radio manual and some on-line clarifications), they will have most of the knowledge needed to effectively use HF-DSC for Distress signaling, etc...
But, if they choose to remain ignorant that is their choice....

I can do my own sail repair, but will NOT be very good...and will look like a child did it....
So, I choose to have professionals do my sails...(yes, at sea or in emergency I CAN do it, and I do have a full sail repair kit on-board)
Same for refrigeration....I understand how it all works, and can jury-rig a fix if needed, but choose to have professionals do any repairs, etc....
Same for welding SS or Alum....I'm a trained / certified welder and machine tool operator, but haven't done any of that in almost 30 years, and even then I never did it for a living...
So, if I need something welded, I hire a pro...

My point is that while everyone has different talents/abilities, when sailing/cruising/voyaging (especially offshore / across oceans), in my opinion, we should all know at least the basics...like sailing handling / trim, navigation, seamanship, and communications OPERATIONS (not knowing how-to build / install the radio, but how-to operate it effectively!)
Over the recent years, we've all seen expert pilots discuss air disasters, with the phrase "aviate, navigate, and then communicate"....which has always seemed to be about right for offshore sailing as well...(sail the boat, navigate, and then communicate...)




To sum up, I'll leave you all with one last FACT...
My late father, who together with my soon-to-be 94 yr old Mom, taught me boating, sailing, navigation, etc. as a kid....
My Dad was the least technical sailor I ever met!!
And, I taught him in only a few hours at the Nav Station how-to use an SSB radio (that was back in the 1970's, well before DSC, GPS, etc.!!!)
And, while he never liked talking on the radio, he knew how AND knew ho to use it effectively!!
Heck, back then (~ 40 years ago) he sometimes found it easier and cheaper to use the SSB to call AT&T Hi-Seas (WOM or WOO) from the Med, to make phones back to the states, as there weren't many international phones and lines available in many areas those days!!

So, here's my last FACT of the day...
It's NOT rocket science!!
If my non-tech Dad could learn it in the 1970's ANYONE can!!

And, a modern HF-DSC radio (like the M-802) only requires you to press one button, or a couple button presses, to send out a DSC Distress Call....how much of an expert does that take??


Okay there's more, but I gotta' go...

Quote:
Originally Posted by accomplice View Post
SSB/HF/DSC technology has failed, in that regard, to provide intuitive and reliable communications to those who have only minimal experience with the systems.
I agree that some of the equipment design is poor for layperson use....but that shouldn't indict the whole of DSC technology??

A billion people around the world can pickup a cellular phone and use it without extensive training. Newer satphone devices offer similar user experiences.

Perhaps the sales volume is too small to justify the investment, but in an ideal world, HF/SSB communications systems would have automatic built-in diagnostics and self-check, and would require no greater expertise to operate than that possessed by the average 7 year old child.

HF/SSB, particularly with DSC, is a powerful tool, and one that cruisers who find themselves offshore or far from other terrestrial forms of communication should be familiar with. The equipment and systems designers, though, have done a great disservice to the technology by not making it easy enough for someone's child or grandmother to use.

KA4WJA, you have made some excellent videos demonstrating the use of HF DSC. That these important videos were made, and are needed, is evidence that the technology is inadequate.
Gotta' go...family matters...

John
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Old 07-04-2015, 02:25   #52
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Re: Is an SSB/pactor modem worth it?

Of course I don't mind, KA4WJA, if you disagree with me a bit - especially if done politely. It is through such disagreement that ideas can be furthered and built upon, consensus garnered, and things learned.

I do not mean to say that the choice of FSK was a poor one. Designing an FSK modem is relatively simple. One might debate that n-PSK, QAM or CDMA or alternate FEC would be a more efficient use of channel capacity, but that isn't the issue at all -- FSK is fine (and certainly much better than voice). The issue is that the whole system/network design is not user friendly.

Consider that an HF/SSB modem would look far more at place in an engineering lab than it would in the window of an Apple store.

For example, above you (rightly) criticize the use of 2182 frequency -- but when one picks up a modern mobile phone one doesn't question whether the device uses 700Mhz or AWS -- the device simply works (or it tells you that it doesn't). Since a DSC equipped radio knows where it is, and presumably knows where it is trying to reach, one would hope that it would have the smarts to know what frequency to use.

There's nothing wrong with FSK per se, or HF (or any other band) -- but the system was so poorly thought out from a user perspective that despite the need for multi-billion dollar satellite systems, many users pick DeLorme, SPOT, etc. instead -- those folks paid attention to the user exper-experience.

I think the problem is that the DSC/HF system was designed by radio experts for use by radio experts. Yes, with great videos like the ones you make less-experienced people can use the systems -- but my point is that they shouldn't have to.

I don't think, when I get in my car, that I need to advance the ignition timing as the engine starts or open the choke as the engine warms. Technology has advanced such that it takes these concerns away from the user. In this respect, DSC/HF has failed to modernize and make itself similarly accessible. No, it isn't rocket science, but it is not as approachable and easy to use as it should be -- and that is why people have developed alternatives.
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Old 07-04-2015, 04:44   #53
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Re: Is an SSB/pactor modem worth it?

Well, I think you're both right

It's true that HF radio is not idiot-proof, and it's not plug and play. It's yet another craft which the busy small boat skipper is asked to master. It's not like on a ship where you have a number of people who divide all these skill sets between them. We have to be able to do it all, and a jack of all trades is often a master of none. So naturally many sailors bridle at acquiring yet another fairly complicated craft.

On the other hand, isn't learning a number of different crafts one of the great joys of this sport? For me it is. And as John said, the skills needed to be a competent HF operator for our purposes are not rocket science. Far simpler than, say, navigation (although some of us don't want to learn this, either), or even collision avoidance (ditto).

So this does come down to individual taste. But great kudos due to John for making HF radio so accessible to so many people A great public service.
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Old 07-04-2015, 06:20   #54
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Re: Is an SSB/pactor modem worth it?

I agree, Dockhead. Kudos to John for the excellent videos.

I'm not sure this is the right thread for it, but it does raise an important topic. While I may be an expert, or at least competent, in the many systems onboard, my crew may not be. If I were to become incapacitated during a passage, would my crew know adequately how to use the systems? Would they know how to seek medical advise and assistance for me, for example? I am fortunate to have a "communications officer" -- one of my regular crew is a retired airforce civil servant who spent his career designing and installing avionics -- but if he were not onboard, would the others know how to use the HF/SSB, or any of the other myriad of systems?

What do others do about such issues?
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Old 07-04-2015, 07:04   #55
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Re: Is an SSB/pactor modem worth it?

Accomplice-
Several of your points totally ignore the realities of a commercial market. Apple can spend money on "design" because they make huge profits. They serve a niche market, overall, but I'd bet that any one Apple store has more sales than all of the recreational marine SSB market in the Western hemisphere. So you're going to keep seeing klunky modems that are built in cheap commercial housings, until you can find a way to justify spending a hundred grand on a design studio, and another hundred grand on molds and dies, and somehow, taking that out of profits year after year.
Same thing with what you do and don't have to know about your car. There's a thousand dollars in the engine computer, and maybe two thousand more in the hundred (literally) sensors that tell it how to run things, and that's three grand up front on goods that are produced and sold in quantities of hundred millions annually.
Your SSB could be just as smart--if it had that kind of market support.


Of course, it would need to know propagation conditions (download and update daily) plus active stations (test communications to each or all, daily) as well as weather (download again) and it would need to raise the background traffic level on the SSB channels significantly in doing this, since now hundreds of "silent" transmissions for this data would be taking place from all the SSB radios.


It ain't rocket science, that's right. But it is a non-trivial task that would need to be supported by an expensive development program, a standards body or ITU standards team, and then replacing all the current equipment, and, right, we'd have to install them in every car or something in order to get the mass market support.


The phrase is "economically unfeasible". Economics trumps technology every time on the mass market.


Smartphones? AWS vs 700MHz? Oh yeah, buy a smartphone at random and try to use it with a similarly selected carrier ("That ad sounds good") and see if it works. That's actually a market demonstration of totally incompatible equipment (in the US) where you buy a proprietary piece of hardware, that can be used only with one carrier, again at huge profit margins in a huge market volume. And while a lot of those people get surprised now (thinking they can switch from AT&T to T-Mobile and still have everything work, for instance) but wait another two years, when the obsolete 2G technology that has been hiding a lot of incompatibilities is SHUT DOWN and they are all orphaned.
It is simple enough to buy another phone at WalMart or 7-11, a wee bit harder to buy an SSB communications setup at sea. Or, in fact, at the local chandlery ashore.(G)
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Old 07-04-2015, 07:31   #56
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Re: Is an SSB/pactor modem worth it?

I agree with you, Hellosailor, that the economics of building a smart network of consumer friendly devices based on HF/DSC doesn't make sense, but I think it is a chicken/egg problem (in reverse). If the technology is not designed to be sufficiently user friendly there will not be large scale consumer adoption.

I was part of the US delegation to the ITU-T in the 90s (not the ITU-R -- don't blame me!) It was impressive how competition forced the price & cost (and power, area, etc.) of technology down by several orders of magnitude both to encourage and as a result of mass adoption. I don't believe the biggest barrier would be in the fancy plastic and small size -- industry does very well at that if the volume is there. The biggest barriers are in the other things you allude to -- the network/system design (to allow distributed updates without overloading background bandwidth, for example).

As for whether the volume would be there, if one looks at the combined sales projections of satellite tracking and low-bandwidth satellite communications systems one can easily see one's way to the 100M mark. Granted, it isn't the 1B mark of mobile phones, but it is orders of magnitude greater than the offshore recreational marine market.
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Old 07-04-2015, 08:37   #57
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Re: Is an SSB/pactor modem worth it?

If your boat already has an Icom M802 and Pactor 4 on it, by all means, keep it. But if you buy a boat and it has none of the above, I'd guess it would cost up around $4300 to buy the radio, antenna tuner, cabling, backstay antenna, counterpoise and Pactor modem, plus a few hundred for installation, if you can't do it yourself.

So the way I see it, you can buy pretty much any of the sat phones and a decent plan for way less than $4300 - you might get 5 yrs or more worth of airtime for that price.

I think if you could get it all in used condition from another cruiser who doesn't need it, that might be a good deal, but $4300 is a pretty steep price of admission.
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Old 07-04-2015, 10:03   #58
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Re: Is an SSB/pactor modem worth it?

hellosailor,
In addition to what I wrote earlier, I can offer some further info/clarification...
Quote:
Originally Posted by ka4wja View Post
a) HF-DSC is SITOR-B signal...which is Frequency-Shift-Keyed Radio-Tele-Type (FSK-RTTY)....
(and although our maritime HF-DSC uses the "modern" 1970's ASCII code, rather than the "old" 1930's Baudot code, FSK-RTTY has been around a lot longer than I've been alive!!)

b) HF-DSC, being a 100-baud FSK signal in a narrow 400hz (or less) bandwidth, is a very robust communications mode...
And, this "technically" gives it a significant advantage over SSB Voice in both range and reliability, and robustness...which, in the real-world is still a big advantage of 12 - 15db, sort of like having an SSB radio with 3000 - 4000 watts of power sending out your signal! (again, forgive the generality)

e) This is not new technology at all, and has been used quite extensively over many decades and has been widely accepted by both maritime commercial operators as well as others...

f)...Being that the intn'l DSC standards were set and implemented in 1992 (23 years ago) and MF/HF-DSC became mandatory for all signatory nations and all SOLAS vessels in Jan 1999 (16 years ago), and I've been explaining and promoting it since 2001 (14 years ago), and I've been actively using it on my own 47' sloop now for > 11 years....
In my opinion, the technology has not failed us....rather we have failed it.

And, it is up to us to fix our issues, educate ourselves, help each, and allow everyone to make decisions for themselves, based on the FACTS, not just the opinions of ignorant journalists or slick salesmen....no matter how nice or well-intentioned they may be...
Please understand that "digital" doesn't mean all or nothing, here!

HF-DSC uses an error-correcting code, and every character is sent twice, with adequate time-diversity...
(and when sending a DSC Distress call, all of the info is repeated multiple times during the call, which takes about 35-40 seconds.....and of course then the whole call is repeated again and again, every 3minutes, until it is responded to, or you stop the calling, or until electrical power fails which is why GMDSS rules require redundant/automatic electrical supply to the GMDSS/DSC equipment...)

I cannot explain the whole thing here, and even if I did I think most would never read it all as it would be pretty droll....but, if you want just a tidbit, here is just some of the 59 pages of text that describe the DSC system...
Quote:
1.1 The system is a synchronous system using characters composed from a ten-bit errordetecting
code as listed in Table 1.

1.2.1
Apart from the phasing characters, each character is transmitted twice in a time-spread
mode; the first transmission (DX) of a specific character is followed by the transmission of four
other characters before the re-transmission (RX) of that specific character takes place, allowing for
a time-diversity reception interval of:

1.2.1.1
400 ms for HF and MF channels, and




I hope the above alleviates any concern you have?
But, also look at some specifics here in red...
Quote:
Originally Posted by hellosailor View Post
With marine HF SSB DSC still being "just" HF SSB...before I get too happy about that concept, how's it going to work for range?
The "range" is excellent, typically MUCH better than SSB Voice!!
Remember, it has been working great for 2 decades!
And, while there were some issues 15 years ago, with some "distress relays" causing problems, those were solved...
I've found that while the "old fashioned" FSK originally seemed odd to me, the deeper you look into the design of the system it does work wonderfully well....and while newer digital codes can pass more data and/or do it in narrower bandwidths, the ones that are more robust are rather low-speed (and relatively new)....
So, all-in-all, even though HF-DSC might seem a bit "old fashioned" to me, and ironically might seem "new" to many sailors, it IS a fairly modern system that has been very reliable for many years now!


I know, on paper, five watts can go around the world. But now the signal is digital and it must arrive somewhere, in good enough condition to be acted upon. So, considering frequency, propagation, weather, and all the real-world reasons why HF digital transmissions can fail to arrive...
See details above....
But, for those whose eyes glaze over at even the hint of something "technical", maybe the easiest answer to these concerns is this: The HF-DSC system has been effectively and efficiently at use now for 20+ years (mandatory for SOLAS vessels / signatory nations since Jan 1999), and while nothing is 100% reliable, HF-DSC is much more reliable than HF-SSB Voice, and has proven to be so, over the past couple decades!


How much is HF DSC going to depend on "Am I in the shipping lanes?"
No dependency at all....just like all HF signals when beyond groundwave range, it is a skywave mode of communications...
and other real-world range limits?
While the primary goal of a DSC Distress Call is to get your Distress info to a shoreside RCC....if you are in a 3rd world RCC area, and/or in a far remote area, then getting your Distress info to all other vessels is a GOOD thing...
And, when wishing to contact other vessels for non-distress matters, you're most likely going to be looking for vessels near you / in your region (within a few hundred miles, maybe up to 500-600 miles), so you're most likely going to be using 8414.5khz daytime, and 4207.5khz (or maybe even 2187.5khz) nighttime....

My point is this:
HF-DSC range is greater, and the reliability is better, and the data/info transfer is more accurate, and the system itself is more robust, etc. than HF-SSB Voice!!


And then of course, since so many commercial vessels ignore watch-keeping regulations anyhow...Just how many undercrewed freighters actually are keeping their HF DSC equipment on, with a communications watch actually staying within earshot of the speaker?
The beauty of the GMDSS, and in particular the MF/HF-DSC system we are discussing here, is that there is NO need for a radioman / bridge crew to be standing-by a speaker, etc...

But, before I get into that too deep, please remember that the primary goal of a DSC Distress Call is to get your Distress info to a shoreside RCC....if you are in a 3rd world RCC area, and/or in a far remote area, then getting your Distress info to all other vessels is a GOOD thing...and of course if radio propagation is working against you at that time, it's nice to know that in addition to the > 450 MF-DSC Coast stations and > 80 HF-DSC Coast stations, there are many SOLAS-grade vessels out there that will also receive your DSC call...
So, in the most dire circumstances (Distress), in most areas of our cruising routes, we are desiring to get our Distress message to the shore stations that are monitoring these DSC freqs...

Now, as for the lax attitude / poor adherence to rules and regs / poor maintenance of equipment / etc. on some ocean-going vessels....
Yes, these are real issues....but they are NO more an issue with HF-DSC than they are with any other means of communications...and, in my opinion, they are LESS of an issue...because if the vessel is a SOLAS-grade vessel it will need to meet GMDSS requirements for the Sea Areas in is transiting....

And, while I have "argued" this point here many times, and have been told that some SOLAS vessels in SeaArea A3 fulfill their GMDSS requirements with MF-DSC (2187.5khz) and INMARSAT, rather than MF/HF-DSC and INMARSAT, the FACTS are that most SOLAS vessels have an MF/HF-DSC Radiotelephone or a MF/HF-DSC scanning rec / controller for their MF or MF/HF radio....so, most SOLAS vessels are actually set-up to monitor these HF-DSC freqs....
(the GMDSS DSC rules specify 2187.5khz, 8414.5khz, and "one other HF-DSC freq"....but since all of the equipment made that scans those 2 specified freqs, scans then all....the actual effect is that all vessels with a MF/HF-DSC radiotelephone or MF/HF-DSC scanning rec / controller, are set-up to scan all six DSC freqs...)

SOLAS vessels in Sea Area A4 (polar regions) of course are required to have full MF/HF-DSC as well as INMARSAT....

And, if you're in Sea Area A2, with other vessels in that area, you can be assured that all of those required to comply with GMDSS, are monitoring at least 2187.5khz DSC..


And, finally....understand that in addition to the DSC scanning rec, MF/HF-DSC-SSB Radiotelephones, etc. that are part of the GMDSS.....all of these "radiotelephones" (what we call an "SSB" radio) are also SSB Voice radios that are required to be operational on 2182, 4125, 6215, 8291, 12290, and 16420khz SSB, for voice communications....so there is still a need for SSB Voice, AFTER contact is established via DSC...



I've seen a small cruise ship on autopilot with NO ONE at all in the bridge, and I'm not the only one. If there's no one there--the DSC is "off" whether it is on or off.
If the radios are "on", but there's nobody there to hear them, what happens then???
That's a loaded question....but the best answer is:
If a DSC Distress call is received a loud alarm would sound (or should sound), along with a Distress display showing....but a routine / all ships call, etc. would probably just produce a "beep", and a notation on the radio / GMDSS console display...

But, to be honest here....if your looking at DSC to be the saving grace of incompetent crew, it isn't....
Although, it IS better than SSB Voice watches, and SIGNIFICANTLY better than the old SOLAS rules which allowed a "2182khz watch receiver" to do the work, which listened ONLY for the "two-tone distress alarm", except for 3 mins twice an hour, when the bridge crew / radioman was supposed to unsquelch the receiver and listen for any voice Mayday calls....(anyone care to guess how often that would actually happen these days??)

If there's a stored message that no one sees until the next morning...I'm not sure they'd want to admit that, either.


I'm not knocking SSB and DSC here, just want a clearer context.
I hope I provided a clearer context for you here....if not then I suggest you read the 178 page GMDSS Master Plan, along with the additional 59 page DSC Annex....where you'll find all the details needed...
BUT....

But, the bottom line here, for most sailors and cruisers, is that HF-DSC works and works well....and has been doing so now for 20+ years....and the fact that so few are aware of this fact is disturbing, but doesn't discount the fact!


To sum up....the bottom line here, for most sailors and cruisers, isthat HF-DSC works and works well....and has been doing so now for 20+ years....and the fact that so few are aware of this fact is disturbing, but doesn't discount the fact!


I hope this helps...

John
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Old 07-04-2015, 10:12   #59
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Re: Is an SSB/pactor modem worth it?

accomplice,
I just now saw your recent post....sorry, I've not clicked refresh in a while...been busy with family...

But, now that I understand what you meant by the technology failing us....I do see your point....
Yeah, DSC (and the whole GMDSS for that matter) is a bit like that proverbial "horse designed by committee"!!

If we could do it over again, yes there are things to make better....

But, IF the damned "sailing press", and those selling marine electronics would take a few minutes (it's NOT rocket science here) to learn a few things, then the average sailor / cruiser would actually have some easy-to-understand info at their fingertips!!






Quote:
Originally Posted by accomplice View Post
FSK is fine (and certainly much better than voice). The issue is that the whole system/network design is not user friendly.

Consider that an HF/SSB modem would look far more at place in an engineering lab than it would in the window of an Apple store.

For example, above you (rightly) criticize the use of 2182 frequency -- but when one picks up a modern mobile phone one doesn't question whether the device uses 700Mhz or AWS -- the device simply works (or it tells you that it doesn't). Since a DSC equipped radio knows where it is, and presumably knows where it is trying to reach, one would hope that it would have the smarts to know what frequency to use.

There's nothing wrong with FSK per se, or HF (or any other band) -- but the system was so poorly thought out from a user perspective that despite the need for multi-billion dollar satellite systems, many users pick DeLorme, SPOT, etc. instead -- those folks paid attention to the user exper-experience.

I think the problem is that the DSC/HF system was designed by radio experts for use by radio experts. Yes, with great videos like the ones you make less-experienced people can use the systems -- but my point is that they shouldn't have to.

I don't think, when I get in my car, that I need to advance the ignition timing as the engine starts or open the choke as the engine warms. Technology has advanced such that it takes these concerns away from the user. In this respect, DSC/HF has failed to modernize and make itself similarly accessible. No, it isn't rocket science, but it is not as approachable and easy to use as it should be -- and that is why people have developed alternatives.

I don't think delving further off topic will be of any help, or interest, to anyone....so, I'll leave the rest go...


I hope my words in earlier posts are helpful to most of 'ya!


Fair winds..

John
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Old 07-04-2015, 15:38   #60
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Re: Is an SSB/pactor modem worth it?

Not worth the money unless you think wireless is free... lol

Spend $400 for a Delorme InReach Explorer gps tracker and messenger with a $49/month subscription for unlimited text messages (e-mails)... DEAL!

Works every time... no sunspot hocus pocus propagation... lol

See you outdoors... on the water!

BTW - no need to flame me... some of you are just die hard old salts... xxxxHAMS
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