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Notice Re DSC Radios with RTCM SC101
|Author||Topic: Notice Re DSC Radios with RTCM SC101|
posted 07-11-2010 11:19 AM ET (US)
The following notice is from the United States Coast Guard regarding federal regulations covering the manufacture and sale of VHF Marine Band radios and their qualification for digital selective calling (DSC) operation:
--NOTICE FROM USCG WEBSITE---
[Manufacture], importation, sale or installation of RTCM SC101 radios prohibited on March 25, 2011.
The Federal Communications Commission has prohibited the [manufacture], importation, sale or installation of non-portable DSC-equipped radios that do not meet either ITU-R Rec. M.493-11 or IEC 62238 Class D standards effective March 25, 2011. This regulation effectively bans the sale of radios built to the RTCM SC101 standard on that date. A similar prohibition will apply to portable radios effective March 25, 2015 . See 47 CFR 80.225(a)(4).
posted 07-11-2010 11:39 AM ET (US)
For several years the United States Coast Guard has been recommending that recreational vessels that voluntarily equip with VHF Marine Band radios should choose a radio that is qualified to CLASS-D DSC ratings. The ban on manufacture of RTCM SC101 radios after March 25, 2011 (that is, next year's boating season) effectively makes the recommendation of CLASS-D a minimum requirement for voluntarily equipped recreational vessels installing a new radio.These regulations have been in place for some time. Here is a link to the 2009 CFR document which mentions these changes:
"Sec. 80.225 Requirements for selective calling equipment.
"(a) The requirements for DSC equipment voluntarily installed in coast or ships stations are as follows:...
"(4) The manufacture, importation, sale or installation of non-portable DSC equipment that does not comply with either of the standards referenced in paragraph (a)(2) of this section is prohibited beginning March 25, 2011."
posted 07-13-2010 10:02 AM ET (US)
Note that this prohibits "[manufacture], importation, sale or
installation". If you have one, you can keep using it.
posted 07-13-2010 01:05 PM ET (US)
Apparently you can keep using an RTCM SC101 radio, but don't ever take it off the boat--you cannot install it again.
posted 07-21-2010 04:03 PM ET (US)
What is RTCM SC-101, and how do I know if I have one? What's the difference between that and Class D?
What does DSC do anyway?
posted 07-22-2010 08:37 AM ET (US)
All of your questions about the difference between RTCM SC101 and Class-D are answered in an article I wrote several years ago. It is available from
DSC is an acronym for digital selective calling. A DSC radio can be called directly from another DSC radio. The two radios can exchange short digital messages, such as the position of their vessels. In more sophisticated DSC radios, printing jobs can be sent from one radio to another, producing printed output.
DSC radio use is part of the GLOBAL MARITIME DISTRESS AND SAFETY SYSTEM, GMDSS, which has been in the process of being implemented for some time. Governing agencies have been lenient is forcing recreational boaters to convert to DSC radio use.
The RTCM SC101 standard for DSC radios required only a small portion of the DSC features to be provided. Permitting radios to be built to RTCM SC101 was a good way to introduce DSC radios to the recreational boater without forcing the cost of the radio to be excessive. As progress was made in manufacturing of radios to better DSC ratings, the cost of a Class-D qualified radio dropped to a very reasonable price. An excellent DSC Class-D VHF Marine Band radio now costs only about $150. The Standard-Horizon company has been the leader in producing Class-D radios at the best price point.
For several years the United States Coast Guard has been telling recreational boaters that they should install a Class-D DSC radio as a minimum radio. The sunset date of March 2011 makes this recommendation a mandatory minimum.
More information on DSC from the USCG at
posted 10-11-2010 12:32 AM ET (US)
In a release dated August 12, 2010 the U.S. Coast Guard issued a clarification on the use of VHF Marine Band radios rated RTCM SC-101 for DSC capabilities after March, 25, 2011. The USCG now says:
"...after March 25, 2011, radios built to RTCM Standard SC-101 can no longer be manufactured, imported, sold or installed; however, previously-installed radios meeting the older standard may continue to be used."
posted 10-11-2010 08:43 AM ET (US)
The Coast Guard has explained their endorsement of digital selective calling for VHF Marine Band radios in this concise statement, which was issued 15 years ago:
posted 02-18-2011 09:05 AM ET (US)
I am reviving this article because the sunset date of March 25, 2011 is now only a few weeks away. Many retailers are trying to sell off their inventory of VHF Marine Band radios which, after March 25, 2011, will no longer be compliant with FCC regulations. If you plan to purchase a VHF Marine Band radio in the next few weeks, you should be aware of the changes in regulations detailed above.
I recommend you purchase a VHF Marine Band radio that is rated CLASS-D for digital selective calling. Generally the CLASS-D radios are newer designs and offer improved user interface designs, making the radio easier to operate and use the digital selective calling features.
posted 03-22-2015 09:45 AM ET (US)
I am reviving this article because the statutory date of March 25, 2015 is only a few days away. After that date, the prohibitions on the manufacture, importation, sale, and installation of VHF Marine Band portable radios that are not in compliance with either ITU-R Rec. M.493-11 or IEC 62238 Class D standards will be in effect.
Boaters should watch for clearance sales of older portable radios that are not in compliance. Such sales are prohibited by the FCC rules.
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