IEC 61097-9:2025
(Main)Global maritime distress and safety system (GMDSS) - Part 9: Shipborne transmitters and receivers for use in the MF and HF bands suitable for telephony, digital selective calling (DSC) and reception of maritime safety information and search and rescue related information - Operational and performance requirements, test methods and required test results
Global maritime distress and safety system (GMDSS) - Part 9: Shipborne transmitters and receivers for use in the MF and HF bands suitable for telephony, digital selective calling (DSC) and reception of maritime safety information and search and rescue related information - Operational and performance requirements, test methods and required test results
IEC 61097-9:2025 specifies the minimum operational and performance requirements and test methods with required test results for transmitters and receivers capable of voice communication and digital selective calling for the GMDSS operating in either the medium frequency band only or in medium and high frequency bands allocated in the ITU Radio Regulations to the Maritime Mobile Service, as required by Chapter IV of SOLAS 1974 as amended. It is based on IMO resolution MSC.512(105) and takes account of Recommendation ITU-R M.493 for digital selective calling including the automatic connection system.
This second edition cancels and replaces the first edition published in 1997. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
a) the text has been updated to incorporate the provisions of the new IMO performance standards given in Resolution MSC.512(105) and new ITU-R recommendations given in M.493-16. These provisions in particular add new requirements for reception of maritime safety information and for the automatic connection system;
b) the provisions for digital selective calling which were previously in IEC 61097-3 have been incorporated;
c) the provisions for watch keeping receivers which were previously in IEC 61097-8 have been incorporated;
d) new requirements have been added for software maintenance in 4.10 in support of IMO recommendations;
e) new Annex A, Annex B and Annex C have been added for digital selective calling;
f) new Annex D and Annex G have been added for bridge alert management;
g) new Annex E and Annex I have been added for maritime safety information;
h) a new Annex F has been added for the automatic connection system;
i) a new Annex H has been added for equipment manuals;
j) a new Annex J has been added for remote control operation;
k) previous Annex A, Annex B and Annex C have been deleted as they are no longer relevant.
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Standards Content (Sample)
IEC 61097-9 ®
Edition 2.0 2025-06
INTERNATIONAL
STANDARD
Global maritime distress and safety system (GMDSS) –
Part 9: Shipborne transmitters and receivers for use in the MF and HF bands
suitable for telephony, digital selective calling (DSC) and reception of maritime
safety information and search and rescue related information – Operational and
performance requirements, test methods and required test results
ICS 33.060.20; 47.020.70 ISBN 978-2-8327-0466-0
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– 2 – IEC 61097-9:2025 © IEC 2025
CONTENTS
FOREWORD . 13
1 Scope . 15
2 Normative references. 15
3 Terms and definitions and abbreviated terms . 16
3.1 Terms and definitions . 16
3.2 Abbreviated terms . 19
4 Performance requirements . 20
4.1 General . 20
4.2 Power supplies . 21
4.3 Control and indicators . 21
4.3.1 Operational controls . 21
4.3.2 Transmitter controls . 21
4.3.3 Receiver controls . 22
4.3.4 DSC controls and indicators . 22
4.4 Interfaces . 22
4.5 Distress controls . 25
4.6 Control panel priority . 26
4.7 Labels . 26
4.8 Safety precautions . 26
4.9 Manuals . 26
4.10 Software maintenance . 27
4.11 Bridge alert management (BAM) . 27
5 Transmitter . 27
5.1 Frequencies and classes of emission . 27
5.2 Frequency accuracy and stability . 28
5.3 Output power . 28
5.4 Transmitter input . 28
5.5 Permissible warming-up period . 29
5.6 Continuous operation . 29
5.7 Safety precautions . 29
5.8 Power of out of band emissions . 29
5.9 Power of conducted spurious emissions . 29
5.10 Residual hum and noise . 30
5.11 Residual frequency modulation on DSC . 30
5.12 Modulation rate of DSC . 30
6 Receiver . 30
6.1 Frequencies and classes of emission . 30
6.2 Frequency tolerance and accuracy . 31
6.3 Usable sensitivity . 31
6.4 Receiver output . 31
6.5 Permissible warming-up period . 31
6.6 Immunity to interference . 31
6.7 Antenna static protection . 31
6.8 Noise reducer . 32
6.9 Audiofrequency gain control and automatic gain control (AGC) . 32
6.10 Unwanted frequency modulation . 32
6.11 Audiofrequency pass band . 32
6.12 Conducted spurious emissions into the antenna . 32
7 Digital selective calling facility . 32
7.1 DSC capabilities . 32
7.2 Distress message storage . 33
7.3 DSC characteristics . 33
8 Facility for the reception of MSI . 33
8.1 General . 33
8.2 Controls and indicators . 33
8.3 Receiver . 34
8.4 Display device and printer . 35
8.5 Storage . 35
8.5.1 Non-volatile message memory . 35
8.5.2 Message identifications . 36
8.5.3 Programmable control memories . 36
8.6 Alert . 36
8.7 Test facilities . 36
8.8 Interfaces . 37
9 Automatic connection system . 37
9.1 General . 37
9.2 Transmitter . 37
9.3 Receiver . 37
10 Test methods and required test results . 38
10.1 Test conditions . 38
10.1.1 Normal and extreme test conditions . 38
10.1.2 Procedure for tests at extreme temperatures . 38
10.1.3 Test power source . 38
10.2 General requirements . 38
10.3 General conditions of measurement . 39
10.3.1 Arrangements for test signals applied to the receiver input . 39
10.3.2 Normal test signals applied to the receiver input . 39
10.3.3 Arrangements for test signals applied to the transmitter input . 39
10.3.4 Normal test signals applied to the transmitter input . 39
10.3.5 Artificial antennas . 39
10.3.6 Testing frequencies . 39
10.3.7 Bit error rate testing . 40
10.3.8 Measurement uncertainty . 40
10.4 Tests by inspection . 40
10.4.1 General . 40
10.4.2 Power supplies . 41
10.4.3 Operational controls . 41
10.4.4 Transmitter controls . 42
10.4.5 Receiver controls . 42
10.4.6 DSC controls and indicators . 42
10.4.7 Interfaces . 43
10.4.8 Distress controls . 44
10.4.9 Control panel priority . 45
10.4.10 Labels . 45
– 4 – IEC 61097-9:2025 © IEC 2025
10.4.11 Safety precautions . 45
10.4.12 Software maintenance . 46
10.4.13 DSC capabilities . 46
10.4.14 Distress message storage .
...
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