Dsc

[skipperdude]

Just got a new radio and hooked it up to the DSC.**I purchased an Icom 422 with the command mike
It's really pretty cool if interfaced with the GPS.

What do you think?

SD

 

[Marin]

I think every marine radio sold today has to have DSC capability. Even if you don't feed a GPS signal to it, the radio will still do the automatic emergency call bit when you push the red button.

We have an Icom 504 on our boat and it's connected to the Furuno NavNet VX2 for position information so the automatic emergency call will include our position information.

As to the calling feature of DSC using your and your friends' MMSI numbers, we have found that to be a nice but not necessary feature. I suppose there are some situations in which it proves useful but since you end up talking on a working channel anyway, we have found that simply calling on 16 and then switching over is faster and easier. For whatever reason Icom has added a step or two in the DSC answering procedure on their radios when you have an incoming call and this kind of negates any advantage over the simple pick-up-the-radio-answer-and-switch-frequencies process we've all been using for decades.

We used DSC calling on our Desolation Sound trip two years ago. On our Gulf Islands trip last year with the same boat accompanying us we didn't bother with it at all. But I've read posts from other people who feel that DSC calling is the greatest thing since sliced bread. So it all depends on how you like to use your radio. We and the people we tend to boat with almost never use them and when we do it's just to ask or answer a quick question or to get a piece of information, so our transmissions are short and very few and far between. So since we don't use the radio for actual conversation, the DSC calling feature has not proven to be important to us. But that's just us.

The position information in the emergency transmission is a major benefit, however. If you are really having an emergency and trying to evacuate the boat or put out a fire or stop a major water inflow or deal with a serious injury the chances of transmitting position information yourself clearly and correctly are pretty slim. So having it automatically included in the Ch. 70 emergency broadcast is a great idea.

-- Edited by Marin on Friday 9th of July 2010 12:22:50 PM

 

[skipperdude]

I was under the impression that you have to hook the radio to the GPS, or does the radio have a built in GPS? It must. How else would it have the location information to broadcast.

The thing I liked about it was the ability to locate your friends boat via the GPS. It shows up as a blip simmilar to the one of your boat, right on the screen.

SD

 

[Marin]

The radio has no position information on its own--- there is no built-in GPS. But it will broadcast the automatic emergency transmission on Ch. 70 if you push the red button even if there is no GPS connected to the radio. But the transmission will not contain any position data. It will include your vessel information assuming you've previously entered your MMSI number into the radio. You only get a couple of tries to do this, by the way-- if you screw up and don't enter it correctly the radio will lock up and will have to go back to Icom for resetting. This is a universal thing, not an Icom thing. Something to do with Homeland Security I was told.

We've not used the "locate your friend's boat" feature. I assume that you're saying it shows it on the radar screen? They only way it can do that is if the radar knows which way north is and most of them don't unless you buy the black box that tells it. We didn't--- the one for our Furuno is some $500---- so we don't have this capability. We aren't interested in knowing where anyone else's boat is, but feeding compass information to the radar would allow the C-Map charts in the unit to be overlayed onto the radar display. If you have a big enough screen this can be a useful feature, telling you that such and such a return is a nav buoy, not a boat, and so on. But the radar needs the compass information to do this.

We can accomplish somewhat the same thing by setting the plotter to display course up instead of the head up that we normally run. Then we split the screen with the radar and plotter and set the ranges more or less the same. That way we can at least make a comparison between the two displays and determine that such-and-such a return is probably a nav buoy or whatever. * Not as accurate as an actual overlay but it's cheaper

Sorry... went a bit astray from your radio question.

 

[skipperdude]

I thought it came up on the GPS screen not the radar.
I'm not sure but this is how I understood the info in the garmin book.
The friends boat shows on the chart plotter. Makes it easy to find your buddy without having to ask them what anchorage they are in.

SD

 

[Marin]

skipperdude wrote:

I thought it came up on the GPS screen not the radar.

Oh, maybe it does.* I handn't thought of that. *To be honest I've not ever examined the Furuno NavNet manual to see if this feature is available on the plotter function.

*I can see where it would be easy enough to do.* If the radio receives postion data in the transmisison from another boat then it's just matter of sending this lat/long up the wire to the plotter and the plotter can put a target at those coordinates.


-- Edited by Marin on Friday 9th of July 2010 04:45:54 PM

 

[skipperdude]

Got it all set up this weekend. Works great.
The boat you call if you have there MMSI number programed into the radio, will show up on the chart plotter as a boat icon.
When you hail them on the DSC there cordinates are transmitted to your radio and then to the GPS.

SD

 

[koliver]

sshhhhh. If any of my cruising buddies find out their location is available to anyone with the MMSI #, they will be sure to turn off the radio whenever they get to their favorite anchorage.

I've got to get one of those!

trouble is, the prices are falling so quickly, I am waiting for hte DSC, AIS, VHF to fall below $300. Its down below $400 now, so it shouldn't be too long to wait.

 

[skipperdude]

My Radio is an Icom M422.* If you ask me* Icom has a pretty screwed up way of making the connections for the DSC.

The biggest problem is that the wires are about 18 ga and they are co-axel.
*To make the connection you have to strip back the co-axel and twist it up to butt splice to your ground .
Then the data or hot which is about a 24 ga wire gets spliced.
*Call me pickie but I like a nice tight wireing set up. *This just looks ganglie.

The smallest butt splice I can find are the pink or red ones, the ones that are heat shrinkable. They are to big. The only thing I could was to wrap it up with electrical tape.* It seems to me there should be a connection of some sort for that small a ga of co axel.

Sure it works. It just isn't tidy.

SD

 

[Baker]

There are radios that have built in GPS's. And in order for your buddies to show up on your plotter, they have to broadcasting their position....IOW, their radio has to be set up(feature enabled) and interfaced with a GPS(whether built in or not). If they are not broadcasting position, you will not see their position. Now there may be certain manufactures and models that "default" to the position braodcast mode once an MMSI is entered...I don't know. But there is no magical position finding capability of the radio.

With all that said, I like DSC calling(we call it SELCAL in the flying business) so you are a little bit more private and you don't have eavesdroppers following you around on the frequencies. Another nice touch is that you choose the channel you want to switch to before you call so when the other person answers, they are automatically switched to the channel of your choosing. So it does make things more efficient.

 

[Marin]

Baker wrote:

we call it SELCAL in the flying business

John--- They still use Selcal in commercial aviation?* That is ancient tecnology.* I used it once in the mid-1970s when we were producing a national TV spot for United Airlines.* The airline was in the process of changing its paint scheme over to the all-white fuselage with the orange, red, and blue stripes that ran down the window-line of the fuselage, which was a dramatic departure from the previous "bow wave" white, blue, red, and silver livery.* At the time we were shooting the commercial the fleet was only about half-painted.* We were waiting to shoot the arrival of a 747 at HNL but nobody with the airline in Honolulu knew if the plane coming in had the new paint job or the old one.

So I called the FAA Center which at the time was housed inside Diamond Head crater (maybe it still is) and they gave me a Selcal connection to the flight deck of the incoming plane.* It was at this point that I learned that airline pilots are no more observant than their passengers.* I asked the captain if his plane had the new paint scheme, and he said he had no idea.* He asked the first officer and the flight engineer if they knew.* The first officer didn't but the flight engineer, who said he had done the walk-around, said he thought it had the new paint scheme.

So on the strength of this we kept our very expensive film crew and equipment waiting for another hour and a half until the plane arrived, and when it did, of course it had the old paint scheme.* So ten grand or so pissed away.

I'm assuming it's the same system that you're talking about.* Back then, everybody pronounded it "Sell Call" so maybe the system you're talking about is newer or different.

*

 

[skipperdude]

What radio manufacturer has the built in GPS?
I can only find the handheld. Does no good for DSC installation. You can't hook a handheld to a Chart plotter

-- Edited by skipperdude on Monday 12th of July 2010 12:43:38 PM

 

[Baker]

Marin, I think the term "Sell Call" but spelled SELCAL is the same and the technology might be the same or has evolved. We don't "talk" over it but it is just a calling feature...and the term comes from what we are talking about....Selective Calling....just not prefaced with "digital" in front of it. Every airliner out there has a SELCAL identification that is usually 4 letters. It is still used mostly on Oceanic flights that allow ATC to get in touch with you over HF frequencies. Since monitoring HF frequencies is difficult and tedious, this just allows them a way to call you without using voice. In our more modern aircraft, we have satcom and CPDLC(Controller/Pilot datalink Capability). We just text message back and forth while in Oceanic airspace. The SELCAL is a backup if for some reason we lose CPDLC capability.

So basically, we are talking about the same thing and it has been around for a VERY long time. Whether our airline stuff is digital...I have no clue....All I know is WFFLT(pronounced "Whiffle Tee") and PFM....Works Fine Lasts Long Time....and Pure F*&king Magic!!!

-- Edited by Baker on Monday 12th of July 2010 01:06:44 PM

 

[skipperdude]

So, this morphed into an airforce thing.

Does anyone find this DSC thing to be of interest? If you have DSC on your radio have you hooked it up? Or do most of you still have old but still working VHF.

To me this is almost as good as an EPIRB.
Also makes your radio almost like a cell phone.

My GPS is an older Garmin 498. But the wire is all there. It also has the wire for the loud hailer. That is working also.

I'm not that much of a techno geek. I bought the radio becaus I think a good radio is very important. But as long as the bells and whistles are there why not hook it up.

SD

 

[Marin]

skipperdude wrote:Does anyone find this DSC thing to be of interest? If you have DSC on your radio have you hooked it up? Or do most of you still have old but still working VHF.

We have it hooked up (but not to display another boat's position) but the only real value I see in it is the automatic emergency broadcast with position data.* The communications aspect as well as the showing a calling boat's position on a plotter I don't see any use for as far as our boating is concerned.* The multiple answering steps that Icom has in their process makes calling on 16 and then switching to a working channel faster and less hassle than making a communication connection with DSC.* Other makes of radios might not have the multiple answering steps that Icom has, I don't know.* The position display of the boat we're talking to is of no interest to us--- if I want to know where they are I ask them.

But as I said, we rarely use the radio (we have it on, we just don't talk on it) unless we need to exchange specific information with another boater.* On cruises where we are out by ourselves we never talk on the radio.* On cruises where we are with or are meeting another boat the only communication we might have it to get dock or anchoring information if the other boat is ahead of us.

People who travel all the time with other boats and who like to talk about all sorts of stuff while underway probably find DSC more useful.

*

 

[Codger2]

Marin wrote:The position display of the boat we're talking to is of no interest to us--- if I want to know where they are I ask them.

Fishermen in my area like their buddy's position icon on their chart plotters as they know when & where they have hit a hot spot. They don't like broadcasting over a regular VHF channel as every fishing boat in the area would descend on them.

My DSC is hooked up but like Marin, I would only use it in an emergency.

*

 

[Tidahapah]

I have a couple of Navman (Northstar) VHF s one with DSC the other without.
I only have the DSC for emergency use.
The GPS feed is into the radios and gives a lat and long on the radio display which I find handy when giving ones position to another station as you dont have to be looking at the plotter or GPS readout.
This feature is also handy in an emergency for someone not totaly familiar with the boat.

Benn

 

[Sailor of Fortune]

Dsc alarms are causing hate and discontent in New York harbor and probably other busy ports. The DSC alarm goes off on someones radio and every VHF in range automatically
gets switched to ch 16. Tugboats landing huge barges talking to deckhands are suddenly
off chnl. Pilots and all bridge communications stop between ships and other traffic is interrupted continuosly-every 3 minutes until the radio is tracked down! Several times last winter this occured for 3-4 days straight 24/7. Most annoying and very dangerous

 

[Peter B]

I don't have DSC, but I have often thought if I upgraded my rather cheap but perfectly effective Sitex VHF, ('promoting' it upstairs as I usually do in these situations), I would get one with DSC, as I have the GPS to link it to. However, as others have mentioned they can be a nuisance if hit too readily. As a matter of interest, if it is not linked to GPS, and one hit the emergency call button one one of these radios, what signal does it give out, and what would others hear on their VHFs..? In other words, if it does not give position, and yet it is not a voice call, what does it do?

 

[skipperdude]

Sailor of Fortune wrote:

Dsc alarms are causing hate and discontent in New York harbor and probably other busy ports. The DSC alarm goes off on someones radio and every VHF in range automatically
gets switched to ch 16. Tugboats landing huge barges talking to deckhands are suddenly
off chnl. Pilots and all bridge communications stop between ships and other traffic is interrupted continuosly-every 3 minutes until the radio is tracked down! Several times last winter this occured for 3-4 days straight 24/7. Most annoying and very dangerous

I never thought of that.
So what is the solution?
*Sounds like no one ever thought of this.
Sounds like it will be OK once you are out of port. or out of range

SD*

 

[Marin]

skipperdude wrote:

Sounds like it will be OK once you are out of port. or out of range

These things go off every so often up here.* When they do, everybody's radio all through the San Juans*or the Gulf Islands or both places howls.* My guess is that the signal is such that it is very easy to pick up and for the radio to react to even if it's weak. So I don't know what the range is, but it's a lot more than just being out of port.* You need to be out of the entire area.

*

 

[Sailor of Fortune]

Alarm sound is a defening loud alarm. You surely will know it when it happens! It will scare
the hell out of you the first time you hear it.

 

[Baker]

A false alarm does not happen too often around here. Almost all DSC radios have a guarded switch. I would assume all "false" alarms to be intentional and done with malice(read kids playing here). I seriously doubt they are done by someone accidently bumping a button. I have heard only one around our area since their proliferation....and yes, it is loud!

 

[Forkliftt]

A few weeks back I installed a new antenna a WM VHF650 radio with DSC. I had already applied and gitten my MMRI number and entered it in the new radio. I dug out my Garmin plotter book and read the section on connecting to a plotter. Wired everything in using the accesory cables on each for the NMEA "hookup". I guess I'm ready to go- but am not sure how to test the thing. Maybe I should push "the button"?

 

[Baker]

....or not!!!...

 

[skipperdude]

If you know someone else with the DSC get there mmsi number and programm it into your radio then press DSC.

If you have it hooked up to your plotter (I have a garmin )It will come up on your screen as a boat icon.

both *radio's should then switch to a pre determined*channel.

SD*

 

[skipperdude]

Forkliftt wrote:

A few weeks back I installed a new antenna a WM VHF650 radio with DSC. I had already applied and gitten my MMRI number and entered it in the new radio. I dug out my Garmin plotter book and read the section on connecting to a plotter. Wired everything in using the accesory cables on each for the NMEA "hookup". I guess I'm ready to go- but am not sure how to test the thing. Maybe I should push "the button"?

Steve,
*All you have to do is press the DSC button not the red one.* It is a great little toy. Sort of makes your radio act like a cell phone.*

when you hit the DSC*button the radio will ask whom to call**i.e. all ships, individual group and so on.
If it is individual you can scroll down to whom ever's number and name you have entered .
Hit DSC again the radio switches to channel 70.*and say's waiting for acknowledgement.*
*Any one with the radio turned on that has DSC will*hear a series of beeps if you hear the beeps you hit the DSC.*Both your radio and the boat you are calling will switch to channel 8.**
*No one will know. No eves dropping.*
You can send a position report*if you like*and the*GPS*numbers will show up on the radio. On the GPS plotter if it is hooked up. It shows an icon for the* boat.

It really is a great way to keep in contact with just those you choose.

If you hit the red button you know what that does.

SD*

*

 

[Baker]

SD, it will switch to whatever channel you were on when you began this operation. So if you want to talk on 68, you turn it to 68 and then do what you said above. When they answer, it will switch them over to 68 automatically. You may know this but it sounded like you were saying the default was always Ch 8. And I know all radios are different but if I am receiving a call, all I have to do is hit the transmit button to answer it and the freq change occurs automatically....IOW, pick up the mic and talk just like would do if your phone was ringing. It also has caller ID so you know who is calling. If it is somebody you already have programmed, their name will show up. If not, it will just be an MMSID number....just like a cellphone would work.

 

[Larry M]

We have the DSC hooked up on our VHF and SSB/Ham radio.* One GPS feeds booth.* The SSB/Ham scans*6 different frequencies.*We hooked them up because they were there.* Will they work?** I'm not so sure.* Most boaters I have talked to don't have theirs*hooked up and*few seem to understand the DSC system.

As far as HF radio goes, most large voice stations (SSB/Ham) have closed.* Commercial shipping (>300 GT) have HF radios as part of GMDSS but are they on?* Our HF radio is on maybe 1-2 hours per day and is used for nets, email or weather.*

Will DSC ever work*as it was intended?* Has anyone heard where DSC was used as a method of rescue?

Larry/Lena
Hobo KK42
La Paz, BCS, MX

-- Edited by Larry M on Sunday 12th of September 2010 04:13:38 PM

 

[Keith]

Absolutely. I have mine hooked up to the VHF and HF. The USCG is continually upgrading their stations to handle these distress calls. I got to see one in operation a few years ago at USCG group San Francisco, right under the golden gate bridge. When you hit the button, it immediately sounds an alarm and prints out a page with your vessel information (assuming you've registered it) and your exact point at the time of transmission. Pretty cool!

Also other DSC equipped radios will sound an alarm when you hit the button.