Disabling DSC

[Delfin]

When a DSC call is received by our Icom 604, the alert is around 120 decibels and basically makes you snort coffee out your nose if you happen to be taking a sip when the siren goes off. According to the manual, this alarm is supposed to go off after a minute or two, but doesn't. We left the VHF on once, locked the boat and when we returned the fire department had been called because people thought such a hallacious noise must mean the boat was on fire. I thought this lunacy was just a feature(?) of the Icom, but sitting at the dock in Vancouver a vessel docking right behind us received a DSC alert on their Raymarine and it was almost as loud so this appears to be built into the system.

Since this results in our frequently cruising with the VHF off to avoid heart attacks or hearing loss it somewhat defeats the safety purpose of the distress calling. So my question is whether anything can be done? Like cut a diode, or drive a 16 penny nail through the right spot on the PCB, or what?

Any suggestions from anyone?

[rwidman]

I'll make a suggestion - Call Icom and ask them what to do.

[Delfin]

Originally Posted by WesK

I'll make a suggestion - Call Icom and ask them what to do.

Done that. They have no suggestions on how to disable a federally mandated function. When asked why their manual said the alarm would turn off after a few minutes but doesn't, their response was "really?" Very helpful.

[ranger58sb]

We have Icom 604s, and when the DSC alert has gone off (yep, coffee snort) I've punched some buttons and the noise stopped. Can't remember what I've pushed, though. One of the DSC "accept" functions or something like that, maybe...

-Chris

[rwidman]

Originally Posted by Delfin

Done that. They have no suggestions on how to disable a federally mandated function. When asked why their manual said the alarm would turn off after a few minutes but doesn't, their response was "really?" Very helpful.

If you had mentioned that in your original post, I wouldn't have bothered you with my suggestion.

[psneeld]

Much better to assume every poster is unable to figure out that a call to a manufactirer could possibly answer the question.

I know it to be true, but sometimes a quick post on TF will answer the question than the 20 minute hold to the manufacturer.

Thats why I love forums and dislike those that always have the "pat" answer, "call the manufacturer/ subject matter pro."

[O C Diver]

I wonder if the DSC has a proximity component? If you removed the GPS signal, would it still sound the alarm?

Ted

[rwidman]

I haven't had a DSC call in the eight years I've owned my boat and radio so I haven't had that problem.

I wonder if other owners of the same radio have the same problem and what they are doing about it?

Now here's the question (and I assume you won't know the answer yourself): Does the alarm use the same speaker that's used for the radio's audio or does it use a separate "buzzer" type transducer? If it's a separate transducer for the alarm, it would be pretty simple to disconnect it or install a series resistor to reduce the volume.

You would probably want to take it to a pro to have this dome to make sure nothing else is effected.

[Delfin]

Originally Posted by ranger42c

We have Icom 604s, and when the DSC alert has gone off (yep, coffee snort) I've punched some buttons and the noise stopped. Can't remember what I've pushed, though. One of the DSC "accept" functions or something like that, maybe...

-Chris

Yes, punching any button does silence the alarm. The problem is the alarm. It would have been SO SIMPLE for them to allow this to be something where the volume could be adjusted. Instead, they assume that you are 500 yards away and need to be able to hear it because you are attending a Black Sabbath concert. Insane.

What bothers me is that this is an important safety feature, and my only defense against bleeding ear drums is turning the VHF off. So, if I could disable the unit's ability to process the DSC signal, that is fine with me.

[psneeld]

Originally Posted by O C Diver

I wonder if the DSC has a proximity component? If you removed the GPS signal, would it still sound the alarm?

Ted

Not sure about every new radio, but up until a few years ago they all sounded the alarm whether registered or hooked up to gps.

In the small commercial operation world...none of that was important and it drove me nuts.

[Maerin]

The DSC alarm will definitely get your attention. I've had a number of them go off, startles the bejeezus out of you, particularly if you're focusing on traffic or navigating a tricky spot- I don't know how to shut mine off, and worse, I have 2 VHF's on the bridge, and they're different models. If one sets to screamin', they both participate.

DSC has gotta be the most never-used technology on the boat. I'm a self-professed geek, a button junkie, if you will. I have NO IDEA how to make DSC work, and when I tried to go through the manual, it just made my head hurt. Of course the ops for the different radios are completely different as well. So when the alarm starts to scream, I make a mad dash for the OFF button!!

[psneeld]

If you travel a lot with a buddy boat, dsc is a good tool to learn to use, otherwise it is just a great rescue option.

[Delfin]

Originally Posted by O C Diver

I wonder if the DSC has a proximity component? If you removed the GPS signal, would it still sound the alarm?

Ted

That's an interesting thought. The unit does display lat/long, which I hardly need. I've disconnected the VHF from the GPS and it will be interesting to see if that does the trick.

Brilliant, OC.

[Drake]

Originally Posted by Delfin

When a DSC call is received by our Icom 604, the alert is around 120 decibels and basically makes you snort coffee out your nose if you happen to be taking a sip when the siren goes off.

I ripped a stitch laughing over that one.

[Delfin]

Originally Posted by WesK

I haven't had a DSC call in the eight years I've owned my boat and radio so I haven't had that problem.

I wonder if other owners of the same radio have the same problem and what they are doing about it?

Now here's the question (and I assume you won't know the answer yourself): Does the alarm use the same speaker that's used for the radio's audio or does it use a separate "buzzer" type transducer? If it's a separate transducer for the alarm, it would be pretty simple to disconnect it or install a series resistor to reduce the volume.

You would probably want to take it to a pro to have this dome to make sure nothing else is effected.

Well, you may be fortunate in that yours apparently doesn't work. We received three of them 2 days ago, and one yesterday. As others have noted, this function is not doing what it is designed to do and no one seems to be able to figure out to make it work appropriately, although all seem to agree it is a colossal PITA.

I'll be interested to see if disconnecting the GPS per OC's suggestion works and I'll let you know if it does. Hope so, but as Mr. Sneed suggests, it may not.

[SaltyDawg86]

Well DSC isn't supposed to be used often.... Ever notice the tab that covers the button says "distress"?

They have classes that teach you about it if you want to shell out the money.

[Delfin]

Originally Posted by psneeld

Much better to assume every poster is unable to figure out that a call to a manufactirer could possibly answer the question.

I know it to be true, but sometimes a quick post on TF will answer the question than the 20 minute hold to the manufacturer.

Thats why I love forums and dislike those that always have the "pat" answer, "call the manufacturer/ subject matter pro."

I suspect Icom probably could answer the question, but won't. I talked with an Icom distributor who also appeared clueless, but he seemed to suggest that the DSC alarm is just a broadcast message like any other. I doubt that, since the signal overrides whatever volume setting you have for regular traffic and punches it up to nose bleed level, plus cancels the alert when you lunge for any button so you can make it stop. So there must be some separate circuitry involved to process this special signal.

[Delfin]

Originally Posted by SaltyDawg86

Well DSC isn't supposed to be used often.... Ever notice the tab that covers the button says "distress"?

They have classes that teach you about it if you want to shell out the money.

I'm suspecting that the 12 year olds who push open that little tab and punch that little button to see what happens may not have taken the course.

[psneeld]

DSC is much broader of a feature than the distress button
..it is supposed to enhance tbe concept of radio telephone.

And yes the distress alarm might be different from routine DSC calls, if you were broadcasting a MAYDAY, wouldn't you wan it to be more noticeable?

[Benthic2]

Could it be this simple ....( link to online manual: file:///C:/Users/Greg/Downloads/M604A_Instruct.pdf)