Winnipesaukee Forum - View Single Post - Marine Patrol will not hear your DSC-VHF distress call

Skipper of the Sea Que · 02-08-2006, 08:42 AM

In the Winter Projects thread, Kamper mentioned buying a DSC VHF radio. Please be advised that NH Marine Patrol at Lake Winnipesaukee is NOT yet DSC capable and the MP does not monitor for DSC distress calls. They do try to keep watch on Channel 16 but on a busy weekend CH 16 can be a nuisance for them to constantly monitor (my opinion). There are still many reasons for recreational boaters to use DSC and there are a lot of fun and useful features.

DSC is used only on Ch 70 and allows “silent monitoring”. You will still hear distress calls, alert messages, group calls or DSC calls directly to your vessel (if you have a Maritime Mobile Service Identity number - no fee to get your unique MMSI number). If one of your friends calls your boat with DSC your radio will work like a pager and you will get the message. The radio will then automatically move you to a working channel for voice communications (the exact process depends on the radio you purchase). You can even see (with a chartplotter) where your friends are, if they want you to see them.

All Marine non-walkie talkie Marine VHF radios FCC type accepted after mid 1999 must be DSC capable. That’s the reason older model non-DSC capable VHF radios have dropped in price.

I spoke with Marine Patrol a few times last month regarding their use of the DSC features of Marine VHF radio. The dispatcher did not know what DSC was but they said they would ask. I called a week later and they were aware of my question and referred me to Lt. Dunleavy. The Lieutenant confirmed that MP did NOT use DSC on Marine VHF. He did tell me that they were going to study the DSC system and that it would be an agenda topic.

So, at the moment, be aware that MP does NOT monitor Marine Channel 70 for DSC distress calls. They also do NOT send out any warnings or alerts using that DSC feature.

More info then you’ll want to read about Marine Radio Communications here ( Too much info on Marine Radio) but answers lots of questions via commentary and links to other parts of their web site. Covers recreational boats up through international commercial vessels. You may not be familiar with a few of the abbreviations they use.
VHF = Very High Frequency, it’s the Marine band that we use around the lake (Marine Patrol often monitors CH 16, the calling and distress channel in use around the lake).
MF = Medium Frequency band
HF = High frequency Band.. Neither MF or HF are used on the lake. Ocean Boaters may refer to either one as Short Wave Radio or Single Side Band.
DSC = Digital Selective Calling. A digital method used on all Marine bands to facilitate communications.

More on marine Radio and use by recreational boaters:
Marine Radio for recreational Boaters

Info on Marine Radio Distress Calls and procedures, click here Marine Radio Distress Calls

02-08-2006, 08:42 AM	#1
Skipper of the Sea Que Deceased Member Join Date: Nov 2002 Location: 1/2 way between Boston & Providence Posts: 573 Blog Entries: 3 Thanks: 32 Thanked 55 Times in 22 Posts	Marine Patrol will not hear your DSC-VHF distress call In the Winter Projects thread, Kamper mentioned buying a DSC VHF radio. Please be advised that NH Marine Patrol at Lake Winnipesaukee is NOT yet DSC capable and the MP does not monitor for DSC distress calls. They do try to keep watch on Channel 16 but on a busy weekend CH 16 can be a nuisance for them to constantly monitor (my opinion). There are still many reasons for recreational boaters to use DSC and there are a lot of fun and useful features. DSC is used only on Ch 70 and allows “silent monitoring”. You will still hear distress calls, alert messages, group calls or DSC calls directly to your vessel (if you have a Maritime Mobile Service Identity number - no fee to get your unique MMSI number). If one of your friends calls your boat with DSC your radio will work like a pager and you will get the message. The radio will then automatically move you to a working channel for voice communications (the exact process depends on the radio you purchase). You can even see (with a chartplotter) where your friends are, if they want you to see them. All Marine non-walkie talkie Marine VHF radios FCC type accepted after mid 1999 must be DSC capable. That’s the reason older model non-DSC capable VHF radios have dropped in price. I spoke with Marine Patrol a few times last month regarding their use of the DSC features of Marine VHF radio. The dispatcher did not know what DSC was but they said they would ask. I called a week later and they were aware of my question and referred me to Lt. Dunleavy. The Lieutenant confirmed that MP did NOT use DSC on Marine VHF. He did tell me that they were going to study the DSC system and that it would be an agenda topic. So, at the moment, be aware that MP does NOT monitor Marine Channel 70 for DSC distress calls. They also do NOT send out any warnings or alerts using that DSC feature. More info then you’ll want to read about Marine Radio Communications here ( Too much info on Marine Radio) but answers lots of questions via commentary and links to other parts of their web site. Covers recreational boats up through international commercial vessels. You may not be familiar with a few of the abbreviations they use. VHF = Very High Frequency, it’s the Marine band that we use around the lake (Marine Patrol often monitors CH 16, the calling and distress channel in use around the lake). MF = Medium Frequency band HF = High frequency Band.. Neither MF or HF are used on the lake. Ocean Boaters may refer to either one as Short Wave Radio or Single Side Band. DSC = Digital Selective Calling. A digital method used on all Marine bands to facilitate communications. More on marine Radio and use by recreational boaters: Marine Radio for recreational Boaters Info on Marine Radio Distress Calls and procedures, click here Marine Radio Distress Calls __________________ Amateur HAM Radio What is it? You'll be surprised. When all else fails Ham Radio still works. Shriners Hospitals *providing specialized care for children regardless of ability to pay*. Find out more or refer a patient.