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Old 09-01-2011, 13:29   #16
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Originally Posted by Dragon Lady View Post
Aren't the emergency numbers directed to the nearest search and rescue center which will also get a fix on your location?
As for turning the system off in a "national emergency" isn't the Satcom network and it's satellites owned by a separate group to any government?
And why do you need a 6ft receiver dish to pick up a signal from a low orbit satellite?
Homeland Security pulls the plug on all domestic satellites including GPS and private communication that are GPS dependent, it's SOP. Even if they don't turn off communication satellites, navigation satellites are down, and hand-held sat-phone cannot find the satellite because the GPS lock won't functioning.
As for size of the antenna; take a look at a freighter sometime and you'll notice those big domes onboard. These are satellite communication antennas. They're big so they can grasp even the smallest scrap of a connection and boost it to be heard. Not only are they tunable, but also auto point to maintain the best connection. The small antenna on the phone is multi-directional and has limited power in and out, (think of battery size that fits in one hand and a 500amp battery in the other) the little antenna (that purportedly will give you a brain tumor in 10 years) while a big (6'+) antenna can crank out enough power to fry a chicken in a few minutes. Think if it as an 800watt microwave as opposed to a 1500watt one except multiply it by a factor of 10. It's the story of size matters all over again.
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Old 09-01-2011, 13:39   #17
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250 boats went in the ARC on Nov 21st. On Nov 22nd I followed listineing to the 50 out of 250 using ssb.

But the time we were half way over there would have been only 20 still using the SSB.

Have a think about that 50 out of 250.
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Old 09-01-2011, 14:01   #18
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250 boats went in the ARC on Nov 21st. On Nov 22nd I followed listineing to the 50 out of 250 using ssb.

But the time we were half way over there would have been only 20 still using the SSB.

Have a think about that 50 out of 250.
I'm sure you don't wear your life-jacket every moment your on board either?
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Old 09-01-2011, 14:09   #19
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250 boats went in the ARC on Nov 21st. On Nov 22nd I followed listineing to the 50 out of 250 using ssb.

But the time we were half way over there would have been only 20 still using the SSB.

Have a think about that 50 out of 250.

not sure of the meaning,,, maybe the others sunk
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Old 09-01-2011, 14:37   #20
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As for being monitored, NObody is monitoring sat-phones
Seahunter, I agree with the overall sentiment of your arguments, that there is still a place for broadcast capabilities (SSB-HF) and DSC in particular, but I don't think the statement quoted above is exactly correct.

The people I know who carry Sat Phones usually have the telephone number(s) of the appropriate Rescue Coordination Center(s) programmed into the speed dial on their phones. Presumably whoever is manning the duty desk at the RCC is as likely to pick up the telephone when it rings as they are to respond to a DSC alert on their radio.

The reason for discouraging reliance on cell-phones for emergency communication is because they don't broadcast. If you broadcast your MayDay or PanPan message, you might get a response from a nearby vessel in the vicinity. From what I heard, monitoring the radio this summer, once communications have been established between the distressed vessel and the USCG, the USCG more often than not was asking the vessel for a cell phone number!
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Old 09-01-2011, 15:02   #21
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Is there something different about SSB DSC that makes it private? VHF DSC only rings the station you're calling then switches to the channel you selected to talk on. Anybody listening to that channel can hear you. They just don't know when you're calling someone, and what channel to go to, but anyone hanging out on that channel will make your conversation not private.

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For those "unfamiliar" with the ICOM801 and misunderstanding regarding DSC, (Digital Selective Calling - USCG Navigation Center) allow me to shed some light. As previously stated there is a certain learning curve required in order to take advantage of all the features on the 801.
Being a DSC radio it requires a MMsi (Maritime Mobile Service Identity - USCG Navigation Center) which is similar to a telephone number specifically given to one radio or ship. This number can be programed (as well as many others) into the 801 for secure transmissions between ship to ship, ship to shore (CG) or ship to other radios on that ship. The key is that the DSC antenna must be installed properly (see ICOM 801 for IDA-yachts).

As for being monitored, NObody is monitoring sat-phones however the USCG is monitoring DSC. The USCG as well as the CCG (Global Maritime Distress and Safety System (GMDSS)(Information for the Fishermen and Recreational Boaters) - Canadian Coast Guard) monitor the emergency DSC channel (National Distress System - USCG Navigation Center). It is important to learn how DSC works in and emergency How to Use Digital Selective Calling (DSC) Radios | Coast Guard News and how to use it for secure ship to ship communications.

The key to any safe boat is to cover your "arse" and the 801 was designed to do just that. After a little programming specifically by you, with information about you and your boat, the 801 can at the flip of a switch, burst transmit an emergency signal with your exact location (GPS connection required) your distress, and the the name of you, your boat, your crew and your MMSI. (which is registered with the FCC and includes information on emergency contacts etc.), This transmission is not only heard by other ships (DSC monitoring is required by commercial ships ~ VHF monitoring is NOT) but most importantly the CG who is monitoring the system. This allows you to do go about taking care of issues like pumping water or what ever. Trying to make a sat-phone call in an emergency is not always going to be that easy. Sat-phone coverage is not global and a storm can definitely put a damper on satellite connections, especially with a hand-held.

The 801 also has HAM capabilities, albeit limited, however in an emergency HAM operators monitoring the airwaves will be more than happy to offer assistance as is there history.

All in all there is really no #1 communication device capable of covering all instances, but the 801 is close. Our choices have been to augment each system with support from another system. We carry on-board communications as well as portable hand-held 2M radios and VHF-DSC hand-helds. We also carry 3 built in VHF stations which we monitor when out (required by law). As previously posted we also carry an Iridium sat-phone, which has mainly been used for internet and calling friends, family and ordering pizza. It's a handy tool we keep charged in our ditch bag. However, one needs to remember, unlike commercial ships, airplanes and the like, you'll not have room onboard for a 6+ foot diameter dish antenna for perfect transmission/receive capabilities for your sat-phone, an advantage the 801 has over other VHFs.

My suggestion, do some research, hopefully some of the links I've supplied will get you on your way.
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Old 09-01-2011, 15:43   #22
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Rely on the sat phone

Avast! The good old USCG is a bit light on the ground, or water, once you are away from the US of A!

As far as I know, nobody, except volunteers and insomniacs monitor the DSC HF channels in Australia and Asia. The VHF DSC channels are monitored by volunteer coast stations in australia during daylight hours. Keep the sat phone or mobile, when coastal cruising, in a water proof case, always at hand, like the President's "football", and when you have 90 seconds to get off, take it with you. You can use it when you step up into your liferaft and things have calmed down a bit? In Asia the coastal mobile network is a lot better than in Australia, almost continious coverage from Thailand, Malaysia right through Indonesia. The sat phone puts you in instant touch with your preferred rescue or response service, no relays.

The HF is great for listening the ABC, BBC and CRI and party line chats, plus sail mail for the emails and weather maps. I have the international radio operators licence and the MMSI numbers are programmed into the VHF and HF, all hooked up to the GPS, but I would not rely on them in an abondon ship in 90 seconds emergency.

It goes without saying that you always have a personal EPIRB with a built in GPS, every crew member should carry one, and it is essential that all watch keepers have it attached to them.

Bottom line is that you are responsible for yourself and if the unthinkable happens you fate is in your hands, and how well you thought out the probable courses of action, rescue is a looooooooooooooong way away or maybe not at all, so look out!! It is not like in the TV rescue or movies.

I reckon that MarkJ means in the previous post is that most of the cruisers gave up on using their HF radios after a short while?

Keep the water on the outside.
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Old 09-01-2011, 16:30   #23
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Originally Posted by Catamount View Post

The reason for discouraging reliance on cell-phones for emergency communication is because they don't broadcast. If you broadcast your MayDay or PanPan message, you might get a response from a nearby vessel in the vicinity. From what I heard, monitoring the radio this summer, once communications have been established between the distressed vessel and the USCG, the USCG more often than not was asking the vessel for a cell phone number!

cal40john: Is there something different about SSB DSC that makes it private?
LOL, yes I agree. But the problem is that "GPS" enabled phones, they aren't really GPS. They merely triangulated via the carriers' network and the CG has to contact the carrier in order to get the exact coordinates. The issue about the CG asking for cell numbers is that in most areas where VHF (not SSB) is monitored, it can get very hectic on 16 and 9 and most of the "users" have limited experience using the radio at best. It's the simplest solution for people who don't, can't or want to learn how to use, or have installed the equipment necessary to save their lives and the lives they have with them. I find it hilarious and horrific listening to the radio during the summer month with the airways filled with "fuel line, fuel tank, fuel filter, fuel this and fuel that" issues.
Best practice is to help these sods out and teach them how to use their equipment.

@ cal40john , on the ICOMs there is a difference with the DSC.
Purpose of DSC

Digital Selective Calling provides automated access to coast stations and ships. The message information is stored in the receiver and can be displayed or printed out following receipt.
There are four levels of priority:


  • distress
  • urgency
  • safety
  • routine They are available for DSC calls. These are private because the polling is digital and only to and including radios with a registered MMSI.
If you read the manual (copy here) http://www.icomuk.co.uk/files/icom/f...ion_manual.pdf you can see that there are a number of different ways to make a DSC call. Ship to Ship is just one. An emergency DSC employs a predetermined frequency, all other DSC transmission fall into other categories. When you make an emergency DSC call (push the RED button) it keeps transmitting until somebody picks up at the other end. Actually it's computer driven. Once the receiving DSC computer picks up the message, it responds to your SSB radio letting you know your transmission was picked up. At the same time it relays your information (name of boat, description, MMSI# and location) to the closest responding station (even internationally for those in Australian water ~hence the big plus of having an SSB). This is why it's important to have the second VHF antenna attached to you ICOM 802 so as to receive those VHF transmissions.

There is NO way a sat-phone can do half of what an SSB radio can do, but if you want to put your life on a piece of equipment that states clearly "DO NOT GET WET" go for it.
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Old 09-01-2011, 17:18   #24
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I wasn't talking about all the different kinds of calls you can make or even the stuff like getting the position of the person you're calling. I looked at the ICOM manual and I don't see that it operates any different than I described for VHF. Once you have called and your party has acknowledged, you go to a regular frequency, ICOM even waits for that frequency to be clear before calling, but anyone listening on the frequency can hear you. It's private in the sense that others don't know that you've made an attempt to call someone and you don't know what frequency the conversation will be on, but anyone just scanning around at random can pick up your conversation and listen in.

John


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@ cal40john , on the ICOMs there is a difference with the DSC.
Purpose of DSC
Digital Selective Calling provides automated access to coast stations and ships. The message information is stored in the receiver and can be displayed or printed out following receipt.
There are four levels of priority:

  • distress
  • urgency
  • safety
  • routine They are available for DSC calls. These are private because the polling is digital and only to and including radios with a registered MMSI.
If you read the manual (copy here) http://www.icomuk.co.uk/files/icom/f...ion_manual.pdf you can see that there are a number of different ways to make a DSC call. Ship to Ship is just one. An emergency DSC employs a predetermined frequency, all other DSC transmission fall into other categories. When you make an emergency DSC call (push the RED button) it keeps transmitting until somebody picks up at the other end. Actually it's computer driven. Once the receiving DSC computer picks up the message, it responds to your SSB radio letting you know your transmission was picked up. At the same time it relays your information (name of boat, description, MMSI# and location) to the closest responding station (even internationally for those in Australian water ~hence the big plus of having an SSB). This is why it's important to have the second VHF antenna attached to you ICOM 802 so as to receive those VHF transmissions.

There is NO way a sat-phone can do half of what an SSB radio can do, but if you want to put your life on a piece of equipment that states clearly "DO NOT GET WET" go for it.
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Old 09-01-2011, 17:37   #25
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Digital Selective Calling. In order to make a DSC call of ANY kind one needs an MMSI (available from your local FCC) and an SSB radio. When you make an DSC call to your friend with DSC polling. You need an SSB radio (or it's all garbled) AND an MMSI # to complete the call. If you don't recognize the MMSI you don't have to answer a position request or any other DSC call. It's far more secure than the cell phone most people have stapled to their heads.

Please read all the info you want~get the radio ~learn about it: then trash it. I'm not into backseat, backyard or potato couch boaters.
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Old 09-01-2011, 18:04   #26
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Digital Selective Calling. In order to make a DSC call of ANY kind one needs an MMSI (available from your local FCC) and an SSB radio. When you make an DSC call to your friend with DSC polling. You need an SSB radio (or it's all garbled) AND an MMSI # to complete the call. If you don't recognize the MMSI you don't have to answer a position request or any other DSC call. It's far more secure than the cell phone most people have stapled to their heads.

Please read all the info you want~get the radio ~learn about it: then trash it. I'm not into backseat, backyard or potato couch boaters.
Instead of name calling you should read more carefully or learn to read. Hopefully to put it into terms you can understand. You are having a conversation on your SSB with someone whose MMSI you know that was initiated by an individual DSC call. I'm wasting time sitting at my SSB tuning to different frequencies. I hear someone talking, I stop tuning and listen, it's your conversation. It isn't necessarily private.

John
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Old 09-01-2011, 18:06   #27
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Gidday guys and girls...

Have been reading the thread with interest and while we currently have a normal vhf system onboard (as well as epirbs) we have only ever had a receiving only ssb..
Now the time has come for us to upgrade to send/receive ssb, and to probably install a sat phone.. The biggest issue for us is that my wife does most of her work via the net (IT development work) and I have no idea of which system would best suit her needs.. Unfortunatly neither does she.. ..

Is there anyone out there who currently does similar work afloat and can provide some tips?
Mainly we are looking for a semi decent system to transmit data/email either once/twice weekly..

Cheers
Ants
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Old 09-01-2011, 18:14   #28
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As I have posted in other threads in this forum, we found the SSB to unreliable during our crossing from Halifax to Ireland this summer. SSB propagation was terrible last summer. Add to this a steep learning curve for the SSB, as we were schooled in one of the threads that we didn't know what we were doing (physicist and engineer both with advanced degrees.) Conversely, we found our Iridium to be pleasingly reliable.

When you are tracking extreme lows crossing the North Atlantic and you are out in the middle it is comforting to know that you can get updated weather when you want it.

Having used both side by side I recommend the Iridium over the SSB.
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Old 09-01-2011, 18:18   #29
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One more time:
Think simpler, I have a cell number (MMSI) Bob has a cell number (MMSI) you have a cell phone with an (MMSI). I call Bob on his cell phone. Can you hear our conversation even though you cell is on? NO. Even if you were scanning the station with another SSB it would be too garbled to understand. This is NOT VHF, it's not MF, or HF it's DSC. In order for this to work a separate DSC antenna is required (see Icom 802 installation manual).
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Old 09-01-2011, 18:24   #30
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Gidday guys and girls...

Have been reading the thread with interest and while we currently have a normal vhf system onboard (as well as epirbs) we have only ever had a receiving only ssb..
Now the time has come for us to upgrade to send/receive ssb, and to probably install a sat phone.. The biggest issue for us is that my wife does most of her work via the net (IT development work) and I have no idea of which system would best suit her needs.. Unfortunatly neither does she.. ..

Is there anyone out there who currently does similar work afloat and can provide some tips?
Mainly we are looking for a semi decent system to transmit data/email either once/twice weekly..

Cheers
Ants
you can forget IT work with SSB,,, I would consider looking at a separate internet sat system for that

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