IEC 62238-2003 pdf – Maritime navigation and radiocommunication equipment and systems – VHF radiotelephone equipment incorporating Class “D” Digital Selective Calling (DSC) – Methods of testing and required test results.
1 Scope This International Standard covers the minimum requirements for general communication for shipborne fixed installations using a VHF radiotelephone incorporating class “D” Digital Selective Calling. These requirements include the relevant provisions of the ITU Radio Regulations, ITU-R Recommendations M.493-10 where class D is defined, and incorporate the relevant guidelines of the IMO as detailed in MSC/Circ. 803, MSC/Circ. 862 and Resolution MSC.131(75). This standard also specifies technical characteristics, methods of measurement and required test results. Recommended standards for equipment intended to work in high level electromagnetic environments are described and included in annex D. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. IEC 60945, Maritime navigation and radiocommunication equipment and systems – General requirements – Methods of testing and required test results IEC 61162-1, Maritime navigation and radiocommunication equipment and systems – Digital interfaces – Part 1: Single talker and multiple listeners IMO Resolution MSC.131(75):2002, Maintenance of a continuous listening watch on VHF channel 16 by SOLAS ships whilst at sea and installation of VHF DSC facilities on non- SOLAS ships IMO MSC/Circ.803: Participation of non-SOLAS ships in the Global Maritime Distress and Safety System (GMDSS) IMO MSC/Circ.862: Clarifications of certain requirements in IMO performance standards for GMDSS equipment ITU Radio Regulations, Appendix S18: 1998, Table of transmitting frequencies in the band 156 – 174 MHz for stations in the maritime mobile service ITU-R Recommendation M.493-10, Digital selective-calling system for use in the maritime mobile service
4 General and operational requirements 4.1 General The manufacturer shall declare that compliance to the requirements of clause 4 is achieved and shall provide relevant documentation if requested. 4.2 Composition The equipment shall, as a minimum, include – a VHF radiotelephone transmitter; – a VHF radiotelephone receiver; – a channel 70 watchkeeping facility for DSC decoder; – a DSC encoder; and – a DSC decoder. 4.3 Construction The mechanical and electrical construction and finish of the equipment shall conform in all respects to good engineering practice, and the equipment shall be suitable for use on board vessels. All controls shall be of sufficient size to enable the usual control functions to be easily performed and the number of controls should be the minimum necessary for simple and satisfactory operation. Adequately detailed operating instructions shall be provided with the equipment. The equipment shall be capable of operating on single frequency and two-frequency channels with manual control (simplex).
The equipment shall be able to operate on channels defined in appendix S18 to the Radio Regulations (see Annex E). Additional VHF channels outside those defined by appendix S18 to the Radio Regulations may also be provided (see for instance Annexes F and G), but means shall be provided to block any of these additional channels, as may be required by appropriate Administrations before installation on board vessels. It shall not be possible for the user to unblock any blocked channels. (See also ITU-R Recommendation M.1084-4.) In the case of an incompatible working channel request, the unit shall reply “Unable to Comply” with 104 as the first telecommand and 108 as the second telecommand. The equipment shall be so designed that use of channel 70 for purposes other than DSC is prevented. It shall not be possible to transmit while any frequency synthesizer used within the transmitter is out of lock. It shall not be possible to transmit during channel switching operations. 4.4 Controls and indicators The user shall not have access to any control which, if wrongly set, might impair the technical characteristics of the equipment. If the equipment can be operated from more than one position, the control unit provided at the position from where the vessel is normally navigated shall have priority and the individual control units shall be provided with an indicator showing whether the equipment is in operation. The following controls or functions shall be provided: – DISTRESS BUTTON (see 4.5.3): the default shall be an undesignated distress message; – CALL (see 4.5.1): the default (initial display) shall be an individual call; – CANCEL: to revert to the initial display or to silence the aural alarm and visual indication used to indicate receipt of a DSC alert. The cancel function shall take place automatically after a maximum of 5 min of inactivity