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10-01-2011, 17:13
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#46
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Registered User
Join Date: Dec 2010
Location: Liveaboard
Boat: Allied Luders 33, Hull 98, 1971
Posts: 393
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Hi Mark:
I don't doubt that you're right, but frankly I don't think I can afford one.
However, I guess I could buy a used one without service and keep it as a backup, since, as you say, 911 (or 112, etc.) will still be honored even without a sim card. My only problem with that would be how would you test it to make sure it's working?
Also, how do they know where the other sat phone carrying boats are that are close enough to render aid? Do the sat phone companies keep track of everyone and share that info? And what about the luddite just over the horizon with just a SSB and no sat phone? I guess they could patch this all together, but I'm just curious how it all works.
Btw, if you don't mind my asking, which one do you have and about how much does it cost, both initially and monthly? Were you tempted to use it when you lost your forestay? And congratulations on your crossing.
thanks...
don
__________________
don
NV5L
S/V Aurora
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10-01-2011, 17:18
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#47
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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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I bought a used iridium 9500 on eBay two years ago cost $450. Airtime contract is $35 dollars a month running cost around $1 minute
Dave.
__________________
Interested in smart boat technology, networking and all things tech
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10-01-2011, 17:55
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#48
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Registered User
Join Date: Jul 2009
Posts: 776
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Quote:
Originally Posted by nv5l
Yes, DSC can send private digital messages to other vessels automatically on channel 70, but once you switch to another channel for voice communication, it's all back in the open. Other than the digital messages on channel 70, and automatically switching both radios to another channel, there is not magic here.
Actually, I doubt the messages are really private either -- radios just ignored messages not addressed to their MMSI.
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That's only on a VHF, not SSB. SSB has more options.
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10-01-2011, 18:41
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#49
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Registered User
Join Date: Dec 2010
Location: Liveaboard
Boat: Allied Luders 33, Hull 98, 1971
Posts: 393
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Glad we got VHF DSC out of the way.
Btw, I haven't read the manuals you've cited, but I have read the FCC regulations. Unfortunately, I've been unable to locate the specific passages concerning the SSB DSC options you mention. Specifically, I don't see anything about "private" communications, DSC or otherwise.
Here's a link to the current rules: http://www.gpo.gov/fdsys/pkg/CFR-200...ol5-part80.pdf
I'm really interested in this, especially from a national security standpoint, so if you could help point me in the right direction, that would be great.
thanks...
don
__________________
don
NV5L
S/V Aurora
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10-01-2011, 19:19
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#50
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Registered User
Join Date: Jan 2011
Location: Brisbane, Australia
Boat: Warwick 72 custom
Posts: 238
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From our perspective, we have SSB and a Sat phone, we use Inmarsat FB250 terminal, the data rates aren't cheap but if nothing else they are fairly reliable, we use them both for entirely different purposes, while I know things like Sailmail are available with a Pactor modem, we do any emailing via the Sat phone.
The HF is great for communicating with groups of other cruisers, as well as listening in to what others are doing. Anything personal goes over the sat phone. I'm a currency trader, when at sea I use our sat connection to continue my trading, the connection seems to work just fine.
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10-01-2011, 23:15
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#51
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Registered User
Join Date: Dec 2006
Location: Seattle
Boat: Cal 40 (sold). Still have a Hobie 20
Posts: 2,967
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Quote:
Originally Posted by nv5l
Glad we got VHF DSC out of the way.
Btw, I haven't read the manuals you've cited, but I have read the FCC regulations. Unfortunately, I've been unable to locate the specific passages concerning the SSB DSC options you mention. Specifically, I don't see anything about "private" communications, DSC or otherwise.
Here's a link to the current rules: http://www.gpo.gov/fdsys/pkg/CFR-200...ol5-part80.pdf
I'm really interested in this, especially from a national security standpoint, so if you could help point me in the right direction, that would be great.
thanks...
don
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I did go through the manual he linked and couldn't find anything about private DSC channels. There were options on the type of distress you're in that could be selected from a menu, which I don't have on my VHF. There were options on which band to send on or send on all bands. The only text input I could find was to set up names for mmsi numbers and that sort of thing, but nothing about any sort of text messaging. It has the same ask for someones location that I have on my VHF. It does have a menu item to send a safety message that you can limit the geographic area so that the receiving radios outside of that area won't ring up. The DSC antenna was for the second receiver so the radio can detect DSC calls while you are on another channel, but that's just like any VHF that is class A, (or D?), just not bottom of the line SC-101 like I have.
So dunno?
John
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11-01-2011, 06:44
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#52
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Long Range Cruiser
Join Date: Dec 2007
Location: Australian living on "Sea Life" currently in England.
Boat: Beneteau 393 "Sea Life"
Posts: 12,820
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Quote:
Originally Posted by nv5l
Also, how do they know where the other sat phone carrying boats are that are close enough to render aid? Do the sat phone companies keep track of everyone and share that info? And what about the luddite just over the horizon with just a SSB and no sat phone? I guess they could patch this all together, but I'm just curious how it all works.
Btw, if you don't mind my asking, which one do you have and about how much does it cost, both initially and monthly? Were you tempted to use it when you lost your forestay? And congratulations on your crossing.
thanks...
don
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Hi Don,
Cost for mine was free because a Mod on here gave it to me just before we went up the Gulf of Aden In the year I have had it the costs have been about $100 for the SIM card and $50 for the call time. I mainly use SMS at 50 cents per SMS and the person at home uses the website to send SMS to me for free! https://sms.thuraya.com/ (all the sat phoones do free sms from land based computers.)
UKMTO in the Gulf of Aden always called us back as we told them we were on a budget
Rescue coordination on the high seas does NOT go via HF radio, or via small pleasure craft. It runs but a group of international agreements with Australia (AuSAR), Japan, the EU and controlled by the United States. The US one is called AMVER Amver.com - Automated Mutual-Assistance Vessel Rescue System - Home
It works ONLY via EMAIL.
You can, and should enroll before you start a long passage then if there is a response needed you will be sent an email.
If you get into deep do-do you send an email.
I am interested if any cruisers register for this system and have experience with it?
I havent used the system yet as I don't have data cable for the Sat Phone (which is out of range till I get back to the Med)
Finally, you asked if I thought of using the Sat Phone when my forestay broke. If I had coverage I would have SMS'ed Nicolle just to say I might be (further) delayed. But I did not consider doing an emergency call, nor would I, even if I had lost the mast. I was 200 miles directly upwind of some of the Caribbean islands with 100nms of fuel in the tanks. If I had lost the rig I would have drifted to the islands and motored or used the VHF to get a tow.
Ringing in a distress call is as good as waving your boat goodbye, especially in US waters where the USCG think they have a law that says they can require a vessle to be abandoned against the wishes of the captain.
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11-01-2011, 06:51
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#53
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Registered User
Join Date: Sep 2005
Location: Winter land based UK New Forest. Summer months away. Making the transition from sail to power this year - scary stuff.
Boat: Super Van Craft 1320 Power Yacht
Posts: 2,175
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Quote:
Originally Posted by Seahunter
I'd (and the USCG) ( http://www.uscg.mil/d1/sectSENE/docs...%20%283%29.pdf) have to disagree with that statement as the DSC channels are monitored world-wide and here in the US ( http://www.uscg.mil/acquisition/resc...nationwide.jpg) and sat-phones are not (and sat-phones in large are not submersible). It's like cell phone, the USCG constantly advertises, NOT to communicate by phone, because DSC is faster. When you hit the Big Red button on the 801, somebody's going to call back almost immediately. Unlike standard VHF-DSC, the 801 has a "test" transmission setting; try it and see how fast you get a response. I've tried ours with a response from over 1000KNM.
However I do agree with swagman on the EBIRP and the PBIRB idea; although I don't usually put this in the communication category, but the emergency one, along with the life raft, jack-lines and such.
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Not sure everyone is discussing the real world situation.
We've had both an 801 and a Satphone. In 2007 we could not recieve and others could not hear our 801 from half the distance you quote due to bad propagation that year. As you'll no doubt know propagation issues did not harm any satellite signals.........which I guess is why all EPRIB's also use satellites for their signal routing ...............
IMHO anyone making a choice should be reminded they have a greater risk of loosing SSB contact than you would ever risk loosing the ability to make satphone contact. And I say this because it was what we found in practice.
Plus few people arguing the merits of SSB seem to recall that when you can get through to pick up data (via a modem) then the SSB / Pactor kit takes ages. A Satphone datalink could have got it in minutes what our 801 / modem took hours.................
Of course there is the balance of the cruiser net advantages a SSB can provide, but I am afraid nothing anyone has said yet would make me amend my recommendation about what to choose if one only has a limited budget. If you can only afford one piece of kit for longer distance (safety / data / weather ) communication then IMHO the Satphone is still at the head of my list over a SSB.
Plus your EPIRB.
Plus VHF for local DSC.
Cheers
JOHN
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11-01-2011, 07:21
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#54
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Eternal Member
Join Date: Jul 2006
Posts: 4,046
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SSB not reliable? Hmmm....
...Let's see.
There are lots of maritime nets on both marine and ham HF/SSB frequencies. Let's take the record of just one of these....the Waterway Net.
This Net meets every morning at 0745AM on 7268 kHz LSB. It's a ham net which has been in operation every single day for more than 40 years! It provides Bahamas and offshore weather from NOAA, allows cruisers to communicate with one another and with shore-based stations, provides navigational information, and takes position reports from boats underway and stationary.
In 2010 alone it took 5,023 such reports. Yep....five thousand.
Some boats, like Art on Samana (KC0TPG) checked in virtually every day while traveling from Florida to the Chesapeake then back to Florida and the Bahamas. Every day. Despite the sometimes poor propagation conditions and despite having some onboard installation problems which were corrected during the summer.
We recently followed Dave, KO4MI, on his delivery from Oxford MD to the BVI, with checkins, position reports, specialized weather reports, and health-and-welfare reports (ailing family member) every day.
The Net often assists the USCG in locating missing or overdue vessels in its operating area (basically, Maine to the Bahamas) and, sometimes, further afield in the Eastern and Western Caribbean.
This is not unusual. The Maritime Mobile Service Net which operates on 14300 kHz from about noon to 10PM is even more active, and has a longer reach due to its operation on a higher frequency.
The Cruizheimers Net (presently on 6516 USB @ 0830EST) is a very active net on the marine SSB frequencies. They usually have 30-60 boats checking in per day, giving their position reports. They also provide navigational advice and have a "Tech Net" to help solve onboard problems of any kind.
There are lots of others.
Bottom line: HF/SSB is a reliable means of communication IF YOU TAKE THE TIME TO LEARN SOMETHING, SET UP YOUR RADIO CORRECTLY, and GET SOME ON-THE-AIR PRACTICE.
If you just wanna push buttons, better look for another communications alternative.
Bill
WA6CCA
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11-01-2011, 08:19
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#55
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Registered User
Join Date: Dec 2010
Location: Liveaboard
Boat: Allied Luders 33, Hull 98, 1971
Posts: 393
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Hi Bill:
I tend to agree with you (I'm a ham, so I guess I have some bias), but Mark did provide some good information. My guess is that, like many things on a boat, the best solution will involve some sort of compromise. I hadn't considered a sat phone before, but will look into it based on Mark's comments.
take care...
don
__________________
don
NV5L
S/V Aurora
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11-01-2011, 15:07
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#56
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Registered User
Join Date: Jan 2008
Boat: Teak Yawl, 37'
Posts: 3,003
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Quote:
Originally Posted by btrayfors
...Let's see.
Bottom line: HF/SSB is a reliable means of communication IF YOU TAKE THE TIME TO LEARN SOMETHING, SET UP YOUR RADIO CORRECTLY, and GET SOME ON-THE-AIR PRACTICE.
If you just wanna push buttons, better look for another communications alternative.
Bill
WA6CCA
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Tell me again how to fix the propagation problems that regularly impact the reliability of getting data/comm via SSB in a timely manner.
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11-01-2011, 15:23
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#57
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Eternal Member
Join Date: Jul 2006
Posts: 4,046
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You don't "fix" them. You work around them.
1. By choosing the right frequency and the right station distance for prevailing time and propagation conditions;
2. By being flexible: if you can't make contact with a PMBO now, you may very well be able to make contact in a few minutes or a few hours;
3. By ensuring that your station is properly set up and operated (metering is a good thing; antenna and ground properly set up; adequate 12VDC power to the radio; suppression of onboard RFI to extent possible; etc.).
4. By practicing and learning what's doable and what's not and why.
Pactor III modems are incredibly robust. They can make good and fast contacts with stations you can't even hear. But you have to be on the right frequency at the right time(s), and the PMBO has to be available and not processing another data stream.
Voice contacts are easier, since potential respondents are located a varying distances and azimuths from your location....from a mile or two to several thousand miles. With some 3 million hams out there, someone's gonna hear you on the ham bands. The marine bands don't have this great abundance of potential respondents, but the USCG and several public correspondence stations are always monitoring several frequencies and are likely to hear you IF you choose the right frequency band for the time and propagation conditions.
How do you know what's "right" for the prevailing conditions? It's a bit of an art as well as science. But one easy way is to tune around the bands a bit and see what you hear.
An excellent way to learn about propagation is to listen regularly on one or two maritime nets. If you do this whenever possible, you'll come to learn how propagation affects communications over certain paths, and how it can change over time...sometimes very quickly. You'll also learn the trends...how the bands tend to "open up" over a given distance at various times of the day.
While all this may sound like a bit of a mystery, take heart that many thousands of operators have mastered the techniques of communicating when they want to.
A final thought: HF propagation over certain distances is quite reliable, day in and day out, on a given frequency. For example, I KNOW I can make good contact with Chuck, ND7K in Marathon, FL (1,003 miles away) on the 40-meter ham band every day of the year between 0745 and 0830. I know this because that's exactly what I do. 100% of the time.
Often when I get up early enough, I also make contact with him -- and others -- via CW on the CW portion of the Waterway Net (7047kHz beginning around 0645-0700).
Bill
WA6CCA
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11-01-2011, 17:38
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#58
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Registered User
Join Date: Dec 2010
Location: Liveaboard
Boat: Allied Luders 33, Hull 98, 1971
Posts: 393
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With all due respect to Mark, DSC is not drivel, especially with respect to VHF close to shore. However, as Mark stated, if you do declare an emergency along the US coast, the USCG will most likely force you to abandon your boat.
DSC can save your life, it's not drivel.
__________________
don
NV5L
S/V Aurora
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12-01-2011, 03:18
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#59
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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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Just to correct some of the mis truths here , neither DSC, HF, or VHf are private all can easily be listened to . DSC is not a text messaging system and there are no agreed standards to allow it to be. It was never the intention . AIS class A has that facility.
Dave
__________________
Interested in smart boat technology, networking and all things tech
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12-01-2011, 20:12
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#60
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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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Inmarsat blue gizmo, @ 600 USD.
I would only use SSB if it was already in the boat or if the things I want to do cannot be done over the phone.
barnie
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