IEC 61097-7:2025
(Main)Global maritime distress and safety system (GMDSS) - Part 7: Shipborne VHF radiotelephone transmitter and receiver - Operational and performance requirements, test methods and required test results
Global maritime distress and safety system (GMDSS) - Part 7: Shipborne VHF radiotelephone transmitter and receiver - Operational and performance requirements, test methods and required test results
IEC 61097-7:2025 specifies the minimum performance requirements, technical characteristics and test methods with required test results for VHF radio installations capable of voice communication and digital selective calling as required by chapter IV of the International Convention for Safety of Life at Sea (SOLAS).
This document incorporates the applicable part of the performance standards included in IMO Resolution A.524(13) and MSC.511(105), the technical characteristics included in Recommendation ITU-R M.489-2 and Recommendation ITU-R M.493-16, and takes account of IMO Resolution A.694(17) which is associated with IEC 60945, and conforms with the ITU Radio Regulations where applicable.
When a requirement in this document is different from IEC 60945, the requirement in this document shall take precedence.
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.511(105) and new ITU-R recommendations given in M.493-16;
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 a received signal strength indicator in 4.3.4 and for software maintenance in 4.6 in support of IMO recommendations;
e) new Annex B and Annex E have been added for bridge alert management;
f) new Annex C and Annex D have been added for digital selective calling;
g) a new Annex F has been added for remote control operation;
h) a new Annex G has been added for equipment manuals.
Système mondial de détresse et de sécurité en mer (SMDSM) - Partie 7: Emetteurs et récepteurs radiotéléphoniques en ondes métriques (VHF), à bord des navires - Exigences d'exploitation et de fonctionnement, méthodes d'essai et résultats d'essai exigés
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Standards Content (Sample)
IEC 61097-7 ®
Edition 2.0 2025-06
INTERNATIONAL
STANDARD
Global maritime distress and safety system (GMDSS) –
Part 7: Shipborne VHF radiotelephone transmitter and receiver – Operational and
performance requirements, test methods and required test results
ICS 33.060.20; 47.020.70 ISBN 978-2-8327-0464-6
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– 2 – IEC 61097-7:2025 © IEC 2025
CONTENTS
FOREWORD . 8
1 Scope . 10
2 Normative references. 10
3 Terms, definitions and abbreviated terms . 11
3.1 Terms and definitions . 11
3.2 Abbreviated terms . 14
4 Performance requirements . 14
4.1 General . 15
4.2 Power supply . 15
4.3 Controls and indicators . 15
4.3.1 General . 15
4.3.2 DSC controls and indicators . 16
4.3.3 Distress controls . 16
4.3.4 Received signal strength indicator . 17
4.3.5 Markings and identifications . 17
4.4 Interfaces and human-machine interface . 17
4.5 Bridge alert management . 19
4.6 Manuals . 19
4.7 Software maintenance . 19
5 Transmitter . 20
5.1 Frequencies and classes of emission . 20
5.1.1 General . 20
5.1.2 Frequency deviation . 20
5.1.3 Audiofrequency band . 20
5.2 Frequency accuracy and tolerance . 20
5.3 Output power . 20
5.4 Permissible warming-up period . 21
5.5 Continuous operation . 21
5.6 Controls and indicators . 21
5.6.1 Channel control and switching . 21
5.6.2 Radiotelephone facility . 22
5.6.3 Loudspeaker and telephone handset (radiotelephone facility) . 22
5.7 Safety precautions . 22
5.8 Antenna system . 23
6 Receiver . 23
6.1 Frequencies and classes of emission . 23
6.2 Frequency tolerance and accuracy . 23
6.3 Usable sensitivity . 23
6.3.1 Radiotelephone facility . 23
6.3.2 Digital selective calling facility . 23
6.4 Receiver output . 23
6.5 Permissible warming-up period . 23
6.6 Immunity to interference . 24
6.7 Controls . 24
6.8 Multiple watch facilities . 24
6.8.1 General . 24
6.8.2 Scanning characteristics . 25
7 Digital selective calling facility . 25
7.1 DSC capabilities . 25
7.2 Distress message storage . 26
7.3 DSC characteristics . 26
8 Test methods and required test results . 26
8.1 Test conditions . 26
8.1.1 Normal and extreme test conditions . 26
8.1.2 Test power source . 26
8.1.3 Procedure for tests at extreme temperatures . 26
8.1.4 General requirements . 26
8.1.5 Tests by inspection . 27
8.2 General conditions of measurement . 27
8.2.1 Arrangements for test signals applied to the receiver input . 27
8.2.2 Receiver squelch facility . 27
8.2.3 Normal test modulation . 27
8.2.4 Artificial antenna . 27
8.2.5 Arrangements for test signals applied to the transmitter input . 27
8.2.6 Transmitter output power . 27
8.2.7 Test of equipment with duplex filter . 27
8.2.8 Test channels . 27
8.2.9 Measurement uncertainty . 28
8.3 Transmitter . 28
8.3.1 Switching time . 28
8.3.2 Frequency error . 29
8.3.3 Carrier power . 29
8.3.4 Frequency deviation . 30
8.3.5 Limitation characteristics of the modulator . 31
8.3.6 Sensitivity of modulator, including microphone . 32
8.3.7 Audiofrequency response . 32
8.3.8 Audiofrequency harmonic distortion of the emission . 32
8.3.9 Adjacent channel power . 33
8.3.10 Conducted spurious emissions conveyed to the antenna . 33
8.3.11 Residual modulation of the transmitter . 34
8.3.12 Transient frequency behaviour of the transmitter . 34
8.3.13 Protection of the transmitter . 38
8.3.14 Frequency error (demodulated signal) . 39
8.3.15 Modulation index . 39
8.3.16 Modulation rate . 39
8.3.17 Residual modulation . 40
8.3.18 Modulator attack time . 40
8.4 Audio general receiver . 41
8.4.1 Harmonic distortion and rated audiofrequency output power . 41
8.4.2 Audiofrequency response . 42
8.4.3 Maximum usable sensitivity . 43
8.4.4 Co-channel rejection ratio . 44
8.4.5 Adjacent channel selectivity . 44
8.4.6 Spurious response rejection . 45
8.4.7 Intermodulation response . 46
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8.4.8 Blocking . 46
8.4.9 Conducted spurious emissions conveyed to the antenna . 47
8.4.10 Amplitude response of the receiver limiter . 47
8.4.11 Receiver hum and noise level . 48
8.4.12 Squelch operation . 48
8.4.13 Squelch hysteresis . 49
8.4.14 Scanning characteristics of multiple watch facilities .
...
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