Cruisers Forum
 


Join CruisersForum Today

Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on Cruisers Forums. Advertise Here
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 11-02-2019, 15:20   #16
Moderator
 
Dockhead's Avatar

Cruisers Forum Supporter

Join Date: Mar 2009
Location: The boat: Cowes (Winter), Above 60N (Summer); me: somewhere in the air!
Boat: Cutter-Rigged Moody 54
Posts: 23,222
Re: HF DSC important enough to warrant a refit?

Quote:
Originally Posted by flyingnut40 View Post
Just curious, which pactor modem did you get when you stole the radio??

Ha, ha. Not "stole" -- you see them at that price from time to time.


It is a nice Pactor II USB, upgraded to Pactor III. Not a Dragon, but quite usable.


The Pactor modem is a lovely device with immensely diverse capabilities.


An M802 with Pactor modem is a fantastic toy, if you have any time between boat repairs to play with it
__________________

__________________
"Parce que je suis heureux en mer, et peut-ętre pour sauver mon ame. . . "
Dockhead is offline   Reply With Quote
Old 11-02-2019, 15:38   #17
Registered User

Join Date: Dec 2016
Posts: 676
Re: HF DSC important enough to warrant a refit?

Quote:
Originally Posted by Dockhead View Post
(enabled through the hidden menu),.
Hidden menu items need to first be unlocked via dealer-only software. Bootleg copies readily available on eBay.

I think I found my 802 + tuner for about $700 but by the time I collected all the fixings to install it, was north of $1K a bit. Of course if you already have an older model installed, there may be less of that. And Hams probably have boxes full of "resources" on hand. No modem as yet. Was just about to pull the trigger but my brother somehow scrambled the transmission on my truck for me. Which I need to fix to re-launch the boat... Modem isn't a "critical path" item ATM.
__________________

toddster8 is offline   Reply With Quote
Old 11-02-2019, 23:00   #18
Registered User

Join Date: Jun 2013
Location: canada
Posts: 2,314
Re: HF DSC important enough to warrant a refit?

when you hit the DSC button on your HF, do you expect boats from 2000 miles away to head towards you to help?

only boats within vhf range would likly come to help. so use the vhf DSC. and your epirb / plb / sat sos for coast guard.
smac999 is online now   Reply With Quote
Old 12-02-2019, 04:22   #19
Registered User
 
transmitterdan's Avatar

Join Date: Oct 2011
Boat: Valiant 42
Posts: 4,830
Re: HF DSC important enough to warrant a refit?

Quote:
Originally Posted by smac999 View Post
when you hit the DSC button on your HF, do you expect boats from 2000 miles away to head towards you to help?

only boats within vhf range would likly come to help. so use the vhf DSC. and your epirb / plb / sat sos for coast guard.

To rescue from so far away, no. But we can expect boats 2000 miles away to perform their obligation to assist with communications and remain in contact with the distressed vessel until no longer needed. Vessels with DSC HF can make the difference in relaying information and ensuring vital information is exchanged back to the boat in distress.

HF radio can do things no satellite system can do. Unless EPIRBs become 2-way devices, HF radio will remain an essential part of blue water safety.
transmitterdan is offline   Reply With Quote
Old 12-02-2019, 06:01   #20
Registered User
 
Jammer's Avatar

Join Date: Jan 2010
Location: Minneapolis area
Boat: Morgan 250, 25'
Posts: 994
Re: HF DSC important enough to warrant a refit?

Quote:
Originally Posted by smac999 View Post
when you hit the DSC button on your HF, do you expect boats from 2000 miles away to head towards you to help?


only boats within vhf range would likly come to help. so use the vhf DSC. and your epirb / plb / sat sos for coast guard.
The practical maximum range for VHF ship-to-ship communications is around 25 miles. I would come to the aid of other boats that are, for example, 50 miles or 75 miles away, if I were the closest source of aid, and I would expect the same of others.

It is my understanding that, exceptions aside, there are no shore stations or ships that maintain a formal listening watch on HF. But in most areas, under most propagation conditions, I would hope for a response from a shore station to a DSC emergency call on HF; as pointed out upthread, commercial traffic within range should also respond and relay communications.

The problem with activating an epirb etc is that it implies that you're ready to abandon ship. If all you really need is some bottled water, duct tape, or ciprofloxacin, it's the wrong tool.


My cruising plans begin with an inland, coastal, and nearshore journey. Some of these areas pose communications difficulties because of the terrain. While the Apostle Islands area is the best example of this -- no VHF or cellular coverage and probably never will be, at least in our lifetimes -- the same situation prevails elsewhere in the Great Lakes and in pockets along the Mississippi and other waterways. I've attached a map of VHF coverage on the Lower Mississippi as an example -- the coast stations are widely spaced, and the terrain blocks the signal. Cellular coverage is iffy for the same reason.


Now, most days, there will be some commercial traffic, but it's not a guarantee, and that's not true in all areas or at all times of year.
Attached Thumbnails
Click image for larger version

Name:	lower miss radio.jpg
Views:	33
Size:	110.7 KB
ID:	185768  
Jammer is online now   Reply With Quote
Old 12-02-2019, 06:18   #21
Moderator
 
Dockhead's Avatar

Cruisers Forum Supporter

Join Date: Mar 2009
Location: The boat: Cowes (Winter), Above 60N (Summer); me: somewhere in the air!
Boat: Cutter-Rigged Moody 54
Posts: 23,222
Re: HF DSC important enough to warrant a refit?

Quote:
Originally Posted by Jammer View Post
. . . It is my understanding that, exceptions aside, there are no shore stations or ships that maintain a formal listening watch on HF. But in most areas, under most propagation conditions, I would hope for a response from a shore station to a DSC emergency call on HF; as pointed out upthread, commercial traffic within range should also respond and relay communications.

The problem with activating an epirb etc is that it implies that you're ready to abandon ship. If all you really need is some bottled water, duct tape, or ciprofloxacin, it's the wrong tool.

HF radio is a formal and legal part of GMDSS, unlike satellite phones other than INMARSAT, so DSC calls (not voice calls any longer) are guarded all over the world by SAR services and coast guards. Unlike any sat phone, you are not calling one particular station -- you are calling everyone, SAR services, coast guard, other vessel -- everyone who has their HF radio switched on, and to whom there is reasonable propagation.



There are many situations where you could want two way communications with someone, and you don't even know whom to call, so that a sat phone is not useful. Even the coded part of a DSC distress message, unlike what an EPIRB sends out, contains basic data about the nature of the distress. And then you can TALK with someone.



EPIRB is fantastic, and I wouldn't leave home without it (and I have a PLB in my life jacket too), but EPIRB/PLB doesn't communicate anything except "Help! Come quick!" and cannot receive any answer or response at all. That's truly just last ditch when you're getting into the life raft and have no other hope. HF radio is something entirely different, which can be used in entirely different ways.
__________________
"Parce que je suis heureux en mer, et peut-ętre pour sauver mon ame. . . "
Dockhead is offline   Reply With Quote
Old 12-02-2019, 06:32   #22
Registered User
 
Jammer's Avatar

Join Date: Jan 2010
Location: Minneapolis area
Boat: Morgan 250, 25'
Posts: 994
Re: HF DSC important enough to warrant a refit?

Anyway, this thread is based on the premise that HF+DSC is useful and asks the question of whether HF is useful without DSC.


I'd like to encourage anyone who wants to have another go at the "HF is useless in the modern satellite and cellular connected world" trope to start another thread.
Jammer is online now   Reply With Quote
Old 14-02-2019, 12:58   #23
Registered User

Join Date: Oct 2007
Location: San Francisco
Boat: N/M 45
Posts: 242
Re: HF DSC important enough to warrant a refit?

I just worked through this question but from the opposite direction - I have an Icom M802 (which has DSC capability) and had never paid attention to it; in that regard the radio is equivalent to one that does not have DSC.

While offshore the VHF radio (Icom M506 with DSC) is always on. The VHF is listening for DSC broadcasts at all times (that's one thing that DSC does). Calls received over VHF-DSC are close enough that I could possibly render assistance or otherwise respond in a useful way. Mostly I get calls from ships that want to test out their VHF-DSC and AIS equipment, in anchorages the VHF-DSC gets used to initiate calls with cruising friends without disturbing everybody on VHF-16. I've not yet received a true DSC distress call (I have received many test distress calls, those are confusing and concerning to work through to establish it's not a real distress call).

I never leave the SSB radio on, it is only on when I want to use it at all other times it is off (SSB draws too much power to leave on). So I did not install the DSC listening antenna and will not be doing so. A call I receive over SSB-DSC is likely to be too far away to respond in a useful way other than to possibly relay communications.

The SSB DSC-distress call function has value on the high seas or in areas where there is insufficient shore-based VHF stations (Australia is one such place - they are set up for HF-DSC only). If you plan to be in such a place then then consider replacing the radio. Otherwise I'd want to eventually upgrade the SSB to one with DSC and place that upgrade near the bottom of my to-do list.

Note that I have Iridium satellite voice capability, in theory I could telephone an individual and request information/assistance. I also have an EPIRB if the boat goes under. Neither of these are quite the same as SSB-DSC, but functionally are close.

- rob
beetle is offline   Reply With Quote
Old 15-02-2019, 08:57   #24
Sponsoring Vendor
 
Sea-TechSystems's Avatar

Community Sponsor

Join Date: Nov 2018
Location: Seattle WA
Boat: 45' Jeanneau Sun Odyssey
Posts: 167
Re: HF DSC important enough to warrant a refit?

How much power is too much? The M802 uses only a dozen or so watts in receive, it only really consumes significant power output during transmit. The absolute maximum it can consume in RX is 3Amps, but it will never likely consume that much inless you have the volume cranked up 100%, RXGain all the way up, squelch off, and there is active loud signal being received. Even then it would consume less when there is no signal being received, so the overall amp hours will be a lot lower.

If you are coastal, then sure the HF DSC is not super useful for you, so it becomes more of a, "should I listen in case someone else needs assistance, even if it's just a relay?". But when more than 100 miles out, it would seem to be prudent to have it on for yourself and any other sailors who may be needing help on the high seas.

Just my opinion of course.

Quote:
Originally Posted by beetle View Post
I just worked through this question but from the opposite direction - I have an Icom M802 (which has DSC capability) and had never paid attention to it; in that regard the radio is equivalent to one that does not have DSC.

While offshore the VHF radio (Icom M506 with DSC) is always on. The VHF is listening for DSC broadcasts at all times (that's one thing that DSC does). Calls received over VHF-DSC are close enough that I could possibly render assistance or otherwise respond in a useful way. Mostly I get calls from ships that want to test out their VHF-DSC and AIS equipment, in anchorages the VHF-DSC gets used to initiate calls with cruising friends without disturbing everybody on VHF-16. I've not yet received a true DSC distress call (I have received many test distress calls, those are confusing and concerning to work through to establish it's not a real distress call).

I never leave the SSB radio on, it is only on when I want to use it at all other times it is off (SSB draws too much power to leave on). So I did not install the DSC listening antenna and will not be doing so. A call I receive over SSB-DSC is likely to be too far away to respond in a useful way other than to possibly relay communications.

The SSB DSC-distress call function has value on the high seas or in areas where there is insufficient shore-based VHF stations (Australia is one such place - they are set up for HF-DSC only). If you plan to be in such a place then then consider replacing the radio. Otherwise I'd want to eventually upgrade the SSB to one with DSC and place that upgrade near the bottom of my to-do list.

Note that I have Iridium satellite voice capability, in theory I could telephone an individual and request information/assistance. I also have an EPIRB if the boat goes under. Neither of these are quite the same as SSB-DSC, but functionally are close.

- rob
__________________
Richard Anderson, SV Mobert. Owner - Sea-Tech Systems - Communications, Navigation, and Weather packages and services for the offshore cruising boat.
Sea-TechSystems is offline   Reply With Quote
Old 15-02-2019, 09:02   #25
Sponsoring Vendor
 
Sea-TechSystems's Avatar

Community Sponsor

Join Date: Nov 2018
Location: Seattle WA
Boat: 45' Jeanneau Sun Odyssey
Posts: 167
Re: HF DSC important enough to warrant a refit?

Quote:
Originally Posted by beetle View Post

Note that I have Iridium satellite voice capability, in theory I could telephone an individual and request information/assistance. I also have an EPIRB if the boat goes under. Neither of these are quite the same as SSB-DSC, but functionally are close.

- rob
In theory you can get help via a satphone, and in practice.. But do you have all the RCC phone numbers pre-programmed into your phone so you can call them when you need it?

Also, an SSB DSC call immediately alerts every ship in range of you, as well as the CG.. You may find, via SSB, that a commercial ship is well within just a couple hours of you and can render assistance, something you are unlikely to be able to do with VHF or a sat phone.

Everything is good to have, I also have Iridium, EPIRB, InReach, DSC SSB, DSC VHF, 3 PLBs.. But being able to immediately raise someone in your general area over radio is alot nicer than hoping Joe Skippy in California can quickly figure out what ships are in your area that can render assistance. And unfortunately, you are far less likely to get a commmercial ship via SSB WITHOUT DSC. They aren't listening to the audio...
__________________
Richard Anderson, SV Mobert. Owner - Sea-Tech Systems - Communications, Navigation, and Weather packages and services for the offshore cruising boat.
Sea-TechSystems is offline   Reply With Quote
Old 15-02-2019, 09:11   #26
Marine Service Provider
 
Scott Berg's Avatar

Join Date: Jul 2011
Location: Aboard
Boat: Seaton 60' Ketch
Posts: 1,101
Re: HF DSC important enough to warrant a refit?

We have both an M802 (configured for DSC) and a ham radio (Icom 756pII that I may upgrade to a new Kenwood or Elecraft). If you have only the budget for one HF radio I'd go with an 802 in a minute. If you have a functioning MARINE HF I wouldn't replace it with an 802 or other SOLAS/GDMSS DSC radio unless your budget could easily absorb it.

If you use your radio for amateur activities you'll find the 802 a pretty fair ham rig with a very good signal. I like a fully featured ham radio so we fit both but we have both the room and the budget. YMMV but if you have a DSC function please enable it and learn about it's features. I've never made a ship to ship HF/DSC call but I know that if I hit the red button every ship in thousands of miles will hear it and engage.
__________________
Scott Berg
WAŘLSS
SV CHARDONNAY
Scott Berg is offline   Reply With Quote
Old 15-02-2019, 11:09   #27
Registered User

Join Date: Oct 2007
Location: San Francisco
Boat: N/M 45
Posts: 242
Re: HF DSC important enough to warrant a refit?

Quote:
Originally Posted by Sea-TechSystems View Post
How much power is too much?
While offshore electron conservation is critical to the battery charging routine that works for my boat; adding a 12 watt continuous draw means I need to turn something else off or add charging capability. Maintaining a listening watch on HF-DSC has value, I'm not questioning that. I do question my ability to do anything useful when the radio picks up an HF-DSC distress call. If the call comes from 150 miles away it's going to be 24 hours before I could get to that position, if there's a need someone to appear on the scene. If someone needs information only (e.g., medical advice), that could be supplied over the radio but I'm not a medical practitioner.

The practicality of conserving electrons has come out above the value of maintaining a listening HF-DSC watch, at least for the capabilities of my boat's electrical setup.

- rob
beetle is offline   Reply With Quote
Old 15-02-2019, 11:22   #28
Registered User

Join Date: Oct 2007
Location: San Francisco
Boat: N/M 45
Posts: 242
Re: HF DSC important enough to warrant a refit?

Quote:
Originally Posted by Sea-TechSystems View Post
But do you have all the RCC phone numbers pre-programmed into your phone so you can call them when you need it?
While not programmed in, I do have the phone numbers for JRCC Honolulu and USCG Pacific SAR on a bit of paper pinned up in the nav station. As my travels to date have been in the Pacific I did call JRCC via Iridium voice call - to report to JRCC regarding communications with an overdue vessel (I heard the overflying USCG plane broadcasting on VHF 16 asking for information from anyone that might have heard something about the overdue boat. The plane couldn't hear me, but I could hear them).

But if my boat were sinking it's highly unlikely I'd think to whip out my not so convenient Iridium phone and calmly place a call - I'd be too busy doing running around everything else.

Quote:
Originally Posted by Sea-TechSystems View Post
You may find, via SSB, that a commercial ship is well within just a couple hours of you and can render assistance, something you are unlikely to be able to do with VHF or a sat phone.
Agreed. Note that if you turn on the EPIRB you're likely to activate the AMVER system and SAR will work to figure out who's closest to you and possibly route a ship towards you. Not as immediate as HF-DSC, there can be a significant lag in the SAR process. But lack of HF-DSC distress calling doesn't preclude a ship showing up where you are. What you won't have in is voice communications with an SAR asset until they are within VHF range - and it would be far better to be able to talk with someone on the SSB before they come charging over the horizon to the rescue - maybe they won't really need to divert. But if that's the case, why would you want to put out an HF-DSC call in the first place?

- rob
beetle is offline   Reply With Quote
Old 15-02-2019, 13:04   #29
Registered User
 
Jammer's Avatar

Join Date: Jan 2010
Location: Minneapolis area
Boat: Morgan 250, 25'
Posts: 994
Re: HF DSC important enough to warrant a refit?

Quote:
Originally Posted by beetle View Post
What you won't have in is voice communications with an SAR asset until they are within VHF range - and it would be far better to be able to talk with someone on the SSB before they come charging over the horizon to the rescue - maybe they won't really need to divert. But if that's the case, why would you want to put out an HF-DSC call in the first place?

Well, you might have a situation that requires assistance but that isn't so time critical as to warrant a diversion of whatever's closest, like contamination of all available supplies of drinking water.


Or you might need medical advice.


Or you might have a situation where what you really need is to take crew on board from another yacht, because you broke your arm or something.
Jammer is online now   Reply With Quote
Old 15-02-2019, 14:14   #30
Registered User
 
El Pinguino's Avatar

Join Date: Aug 2013
Location: Somewhere in Patagonia
Posts: 4,878
Re: HF DSC important enough to warrant a refit?

This may be of interest to some..... 'distress working' by a yacht in the Southern Ocean... with HF and Sailmail but without DSC. Was 11 years ago almost to the day......

Full log of the distress working can be found here in a JSD thread.... Post#3 ...Jordan Series Drogue vs Para-Anchor ?

'.......and so with a feeling of embarrasment, sadness and emptiness in our stomachs we activated the Electronic Positioning Radio Beacon.
We also tried to call on all the distress frequencies using hf radio but had no luck with any contact. Fortunately I had an email facility (SAILMAIL) using hf radio, digital transmissions tend to be far stronger than voice transmission so I looked up the email address of Falmouth Coastguard and sent a mayday by email. The only problem with this type of communication is it generally takes about 1.5 hrs to receive a reply, I have to send the email to a shore station which then sends it on to the receiving station who then replies to the shore station who then sends it back to the ship.
The mayday was sent at 1146z
MAYDAY MAYDAY MAYDAY
SAILING YACHT BRILLIANCE
CALL SIGN MEVV5
POSITION 42 26S 022 14W SOUTH ATLANTIC OCEAN
2 POB
39FT WHITE HULL
AT PRESENT STILL WITH BOAT WE WERE HEADING FOR SOUTH AFRICA SO IN A NE DIRECTION, BUT ARE NOW USING A JORDAN SERIES DROGUE AND SO ARE BEING TRACKED SUBJECT TO WIND AND WAVES WHICH FORTUNATELY AT PRESENT IS STILL NE
EPIRB ACTIVATED
MAYDAY MAYDAY MAYDAY
MAY SOON LOSE MAST AND SO WILL ALSO LOSE ABILITY TO COMUNICATE.

Reply received 1405z

MAYDAY -Yacht BRILLIANCE - M E V V 5
THIS IS FALMOUTH COASTGUARD
We have received your distress message & an EPIRB activation alert.
All details have been passed to Argentina in whose rescue area your position is.
We are speaking to UK authorities in the Falklands to see if there are any assets that can assist.
We will continue to speak to all authorities in an effort to assist you.
What comms do you have on board, including satphone details ?
What lifesaving apparatus do you have on board ?
What are your intentions?
What are your weather conditions?
Falmouth Coastguard' .....

later..... from MEVV5 .. 'ps. we have the castle beach cafe just below falmouth cg so bacon butties all round if we get out of this one and are open for the summer.'
__________________

__________________
Simple Celestial https://www.dropbox.com/s/a5blh1rgvi...ation.pdf?dl=0

A little bit about Chile http://www.cruiserswiki.org/wiki/Chile
El Pinguino is online now   Reply With Quote
Reply

Tags
dsc, import, refit

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
'Enough is Enough!' . . . Yeah ! Right ! JustThinking Meets & Greets 22 21-02-2016 23:18
Looking for a fixed VHF *without* DSC (or ability to disable DSC) susswein Marine Electronics 31 10-11-2014 13:18
Enough's Enough - I Can't Stand No More Charlie Sailor Logs & Cruising Plans 10 16-06-2009 09:44
SLEEP, enough or not enough?? shadow Off Topic Forum 22 17-04-2008 07:29



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 22:12.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2019, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2019, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.