ETSI EN 301 925 V1.6.1 (2020-12)

Final draft ETSI EN 301 925 V1.6.0 (2020-10)

EUROPEAN STANDARD
Radiotelephone transmitters and receivers for
the maritime mobile service operating in VHF bands;
Technical characteristics and methods of measurement

2 Final draft ETSI EN 301 925 V1.6.0 (2020-10)

Reference
REN/ERM-TGMAR-607
Keywords
EMC, GMDSS, maritime, radio, telephony, VHF
ETSI
650 Route des Lucioles
F-06921 Sophia Antipolis Cedex - FRANCE

Tel.: +33 4 92 94 42 00  Fax: +33 4 93 65 47 16

Siret N° 348 623 562 00017 - NAF 742 C
Association à but non lucratif enregistrée à la
Sous-Préfecture de Grasse (06) N° 7803/88

Important notice
The present document can be downloaded from:
http://www.etsi.org/standards-search
The present document may be made available in electronic versions and/or in print. The content of any electronic and/or
print versions of the present document shall not be modified without the prior written authorization of ETSI. In case of any
existing or perceived difference in contents between such versions and/or in print, the prevailing version of an ETSI
deliverable is the one made publicly available in PDF format at www.etsi.org/deliver.
Users of the present document should be aware that the document may be subject to revision or change of status.
Information on the current status of this and other ETSI documents is available at
https://portal.etsi.org/TB/ETSIDeliverableStatus.aspx
If you find errors in the present document, please send your comment to one of the following services:
https://portal.etsi.org/People/CommiteeSupportStaff.aspx
Copyright Notification
No part may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying
and microfilm except as authorized by written permission of ETSI.
The content of the PDF version shall not be modified without the written authorization of ETSI.
The copyright and the foregoing restriction extend to reproduction in all media.

© ETSI 2020.
All rights reserved.
DECT™, PLUGTESTS™, UMTS™ and the ETSI logo are trademarks of ETSI registered for the benefit of its Members.

3GPP™ and LTE™ are trademarks of ETSI registered for the benefit of its Members and
of the 3GPP Organizational Partners.
oneM2M™ logo is a trademark of ETSI registered for the benefit of its Members and
of the oneM2M Partners. ®
GSM and the GSM logo are trademarks registered and owned by the GSM Association.
ETSI
3 Final draft ETSI EN 301 925 V1.6.0 (2020-10)
Contents
Intellectual Property Rights . 8
Foreword . 8
Modal verbs terminology . 8
1 Scope . 9
2 References . 9
2.1 Normative references . 9
2.2 Informative references . 10
3 Definition of terms, symbols and abbreviations . 11
3.1 Terms . 11
3.2 Symbols . 12
3.3 Abbreviations . 12
4 General requirements . 13
4.1 Construction . 13
4.2 DSC operation . 13
4.3 Controls and indicators . 14
4.4 Handset and loudspeaker . 14
4.5 Safety precautions . 15
4.6 Labelling. 15
4.7 Warm up . 15
4.8 Audio Processing . 15
5 Technical requirements . 16
5.1 Switching time . 16
5.2 Class of emission and modulation characteristics . 16
5.3 Multiple watch facilities . 16
5.3.1 Additional performance standards . 16
5.3.2 Scanning characteristics . 17
5.4 Interfaces . 17
5.4.1 General . 17
5.4.2 Audio frequency . 17
5.4.3 Digital interfaces . 17
5.5 Voyage data recorder interface . 18
6 Test conditions, power sources and ambient temperatures . 18
6.1 Test conditions . 18
6.2 Test power source . 18
6.3 Normal test conditions . 18
6.3.1 Normal temperature and humidity . 18
6.3.2 Normal power source voltage . 18
6.3.2.1 Mains powered equipment . 18
6.3.2.2 Battery powered equipment . 19
6.3.2.3 Other power sources . 19
6.4 Extreme test conditions . 19
6.4.1 Extreme temperatures . 19
6.4.2 Extreme values of power source voltage . 19
6.4.2.1 Mains powered equipment . 19
6.4.2.2 Battery powered equipment . 19
6.4.2.3 Other power sources . 19
6.5 Procedure for tests at extreme temperatures . 19
7 General conditions of measurement . 19
7.1 Sequence of testing . 19
7.2 Test channels . 20
7.3 Squelch . 20
7.4 Arrangements for test signals applied to the receiver input . 20
ETSI
4 Final draft ETSI EN 301 925 V1.6.0 (2020-10)
7.5 Normal test modulation of the receiver wanted signal . 20
7.6 Arrangements for monitoring the receiver output . 20
7.7 Arrangements for test signals applied to the transmitter input . 21
7.8 Normal test modulation of the transmitter . 21
7.9 Arrangements for monitoring the transmitter output . 21
7.10 Arrangements for test of DSC . 21
7.11 Standard test signals for DSC . 21
7.12 Determination of symbol error ratio in the output of the receiver . 21
7.13 Reference bandwidths for spurious measurements . 22
7.14 Interpretation of the measurement results . 22
8 Performance checks . 23
8.1 Performance checks - introduction . 23
8.2 Performance check - transmitter frequency error . 23
8.3 Performance check - transmitter carrier power . 23
8.4 Performance check - transmitter audio frequency harmonic distortion of the emission . 23
8.5 Performance check - receiver sensitivity . 23
8.6 Performance check of DSC . 23
9 Environmental tests . 24
9.1 Procedure . 24
9.2 Vibration test . 24
9.2.1 Definition . 24
9.2.2 Method of measurement . 24
9.2.3 Requirement . 25
9.3 Temperature tests . 25
9.3.1 Introduction. 25
9.3.2 General procedure . 25
9.3.3 Dry heat . 25
9.3.3.1 Definition . 25
9.3.3.2 Method of measurement . 25
9.3.3.3 Requirement . 25
9.3.4 Damp heat . 25
9.3.4.1 Definition . 25
9.3.4.2 Method of measurement . 25
9.3.4.3 Requirement . 26
9.3.5 Low temperature cycle . 26
9.3.5.1 Definition . 26
9.3.5.2 Method of measurement . 26
9.3.5.3 Requirement . 26
10 Transmitter . 26
10.1 General conditions . 26
10.2 Frequency error . 26
10.2.1 Definition . 26
10.2.2 Method of measurement . 26
10.2.3 Limits . 27
10.3 Carrier power . 27
10.3.1 Definitions . 27
10.3.2 Method of measurement . 27
10.3.3 Limits . 27
10.3.3.1 General . 27
10.3.3.2 Normal test conditions limits . 27
10.3.3.3 Extreme test conditions limits . 27
10.4 Frequency deviation . 27
10.4.1 Definition . 27
10.4.2 Maximum permissible frequency deviation . 28
10.4.2.1 Method of measurement . 28
10.4.2.2 Limits . 28
10.4.3 Reduction of frequency deviation at modulation frequencies above 3 kHz . 28
10.4.3.1 Method of measurement . 28
10.4.3.2 Limits . 28
10.5 Sensitivity of the modulator including the microphone . 29
ETSI
5 Final draft ETSI EN 301 925 V1.6.0 (2020-10)
10.5.1 Definition . 29
10.5.2 Method of measurement . 29
10.5.3 Limits . 29
10.6 Audio frequency response . 29
10.6.1 Definition . 29
10.6.2 Method of measurement . 30
10.6.3 Limits . 30
10.7 Audio frequency harmonic distortion of the emission. 30
10.7.1 Definition . 30
10.7.2 Method of measurement . 31
10.7.3 Limits . 31
10.8 Adjacent channel power . 31
10.8.1 Definition . 31
10.8.2 Method of measurement . 31
10.8.3 Limits . 32
10.9 Conducted spurious emissions conveyed to the antenna . 32
10.9.1 Definition . 32
10.9.2 Method of measurement . 32
10.9.3 Limit . 32
10.10 Residual modulation of the transmitter . 32
10.10.1 Definition . 32
10.10.2 Method of measurement . 32
10.10.3 Limit . 33
10.11 Transient frequency behaviour of the transmitter . 33
10.11.1 Definition . 33
10.11.2 Method of measurement . 33
10.11.3 Limits . 34
10.12 Radiated spurious emission . 36
10.12.1 Definition . 36
10.12.2 Method of measurement . 36
10.12.3 Limits . 37
11 Transmitter with DSC encoder . 37
11.1 General . 37
11.2 Frequency error (carrier) . 37
11.2.1 Definition . 37
11.2.2 Method of measurement . 37
11.2.3 Limits . 38
11.3 Frequency error (demodulated signal) . 38
11.3.1 Definition . 38
11.3.2 Method of measurement . 38
11.3.3 Limits . 38
11.4 Carrier Power . 38
11.4.1 Definition . 38
11.4.2 Method of measurement . 38
11.4.3 Limits . 38
11.4.3.1 Normal test conditions . 38
11.4.3.2 Extreme test conditions . 39
11.5 Modulation index . 39
11.5.1 Definition . 39
11.5.2 Method of measurement . 39
11.5.3 Limits . 39
11.6 Modulation rate . 39
11.6.1 Definition . 39
11.6.2 Method of measurement . 39
11.6.3 Limits . 39
11.7 Residual modulation . 39
11.7.1 Definition . 39
11.7.2 Method of measurement . 39
11.7.3 Limits . 40
11.8 Modulator attack time . 40
11.8.1 Definition . 40
ETSI
6 Final draft ETSI EN 301 925 V1.6.0 (2020-10)
11.8.2 Method of measurement . 40
11.8.3 Limit . 40
11.9 Adjacent channel power . 40
11.9.1 Definition . 40
11.9.2 Method of measurement . 40
11.9.3 Limits . 41
11.10 Conducted spurious emissions . 41
11.11 Testing of free channel transmission on DSC channel 70 . 41
11.11.1 Definition . 41
11.11.2 Method of measurement . 41
11.11.3 Requirement . 41
11.12 Generated DSC call sequences . 42
12 Receiver . 42
12.1 Harmonic distortion and rated audio output power . 42
12.1.1 Definition . 42
12.1.2 Methods of measurement . 42
12.1.3 Limits . 42
12.2 Audio frequency response . 42
12.2.1 Definition . 42
12.2.2 Method of measurement . 43
12.2.3 Limits . 43
12.3 Maximum usable sensitivity . 44
12.3.1 Definition . 44
12.3.2 Method of measurement . 44
12.3.3 Limits . 44
12.4 Amplitude characteristic of the receiver . 44
12.4.1 Definition . 44
12.4.2 Method of measurement . 44
12.4.3 Limits . 44
12.5 Co-channel rejection. 45
12.5.1 Definition . 45
12.5.2 Method of measurement . 45
12.5.3 Limit . 45
12.6 Adjacent channel selectivity . 45
12.6.1 Definition . 45
12.6.2 Method of measurement . 45
12.6.3 Limits . 46
12.7 Spurious response rejection . 46
12.7.1 Definition . 46
12.7.2 Method of measurement . 46
12.7.2.1 Introduction to the method of measurement . 46
12.7.2.2 Method of search over the "limited frequency range" . 47
12.7.2.3 Method of measurement . 47
12.7.3 Limit . 47
12.8 Intermodulation response . 47
12.8.1 Definition . 47
12.8.2 Method of measurement . 48
12.8.3 Limit . 48
12.9 Blocking or desensitization . 48
12.9.1 Definition . 48
12.9.2 Method of measurement . 48
12.9.3 Limit . 48
12.10 Conducted spurious emissions . 49
12.10.1 Definition . 49
12.10.2 Method of measurement . 49
12.10.3 Limit . 49
12.11 Receiver noise and hum level . 49
12.11.1 Definition . 49
12.11.2 Method of measurement . 49
12.11.3 Limit . 49
12.12 Squelch operation . 50
ETSI
7 Final draft ETSI EN 301 925 V1.6.0 (2020-10)
12.12.1 Description . 50
12.12.2 Squelch audio muting . 50
12.12.2.1 Definition . 50
12.12.2.2 Method of measurement . 50
12.12.2.3 Limits . 50
12.12.3 Squelch operating level . 50
12.12.3.1 Definition . 50
12.12.3.2 Method of measurement . 50
12.12.3.3 Limits . 50
12.12.4 Squelch hysteresis . 51
12.12.4.1 Definition . 51
12.12.4.2 Method of measurement . 51
12.12.4.3 Limit . 51
12.13 Multiple watch characteristics . 51
12.13.1 Definitions . 51
12.13.2 Method of measurement . 51
12.13.3 Limits . 52
12.14 Radiated spurious emissions. 52
12.14.1 Definition . 52
12.14.2 Method of measurement . 52
12.14.3 Limits . 53
13 Receiver with a DSC decoder . 53
14 Duplex operation .
...

EUROPEAN STANDARD
Radiotelephone transmitters and receivers for
the maritime mobile service operating in VHF bands;
Technical characteristics and methods of measurement

2 ETSI EN 301 925 V1.6.1 (2020-12)

Reference
REN/ERM-TGMAR-607
Keywords
EMC, GMDSS, maritime, radio, telephony, VHF
ETSI
650 Route des Lucioles
F-06921 Sophia Antipolis Cedex - FRANCE

Tel.: +33 4 92 94 42 00  Fax: +33 4 93 65 47 16

Siret N° 348 623 562 00017 - NAF 742 C
Association à but non lucratif enregistrée à la
Sous-Préfecture de Grasse (06) N° 7803/88

Important notice
The present document can be downloaded from:
http://www.etsi.org/standards-search
The present document may be made available in electronic versions and/or in print. The content of any electronic and/or
print versions of the present document shall not be modified without the prior written authorization of ETSI. In case of any
existing or perceived difference in contents between such versions and/or in print, the prevailing version of an ETSI
deliverable is the one made publicly available in PDF format at www.etsi.org/deliver.
Users of the present document should be aware that the document may be subject to revision or change of status.
Information on the current status of this and other ETSI documents is available at
https://portal.etsi.org/TB/ETSIDeliverableStatus.aspx
If you find errors in the present document, please send your comment to one of the following services:
https://portal.etsi.org/People/CommiteeSupportStaff.aspx
Copyright Notification
No part may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying
and microfilm except as authorized by written permission of ETSI.
The content of the PDF version shall not be modified without the written authorization of ETSI.
The copyright and the foregoing restriction extend to reproduction in all media.

© ETSI 2020.
All rights reserved.
DECT™, PLUGTESTS™, UMTS™ and the ETSI logo are trademarks of ETSI registered for the benefit of its Members.

3GPP™ and LTE™ are trademarks of ETSI registered for the benefit of its Members and
of the 3GPP Organizational Partners.
oneM2M™ logo is a trademark of ETSI registered for the benefit of its Members and
of the oneM2M Partners. ®
GSM and the GSM logo are trademarks registered and owned by the GSM Association.
ETSI
3 ETSI EN 301 925 V1.6.1 (2020-12)
Contents
Intellectual Property Rights . 8
Foreword . 8
Modal verbs terminology . 8
1 Scope . 9
2 References . 9
2.1 Normative references . 9
2.2 Informative references . 10
3 Definition of terms, symbols and abbreviations . 11
3.1 Terms . 11
3.2 Symbols . 12
3.3 Abbreviations . 12
4 General requirements . 13
4.1 Construction . 13
4.2 DSC operation . 13
4.3 Controls and indicators . 14
4.4 Handset and loudspeaker . 14
4.5 Safety precautions . 15
4.6 Labelling. 15
4.7 Warm up . 15
4.8 Audio Processing . 15
5 Technical requirements . 16
5.1 Switching time . 16
5.2 Class of emission and modulation characteristics . 16
5.3 Multiple watch facilities . 16
5.3.1 Additional performance standards . 16
5.3.2 Scanning characteristics . 17
5.4 Interfaces . 17
5.4.1 General . 17
5.4.2 Audio frequency . 17
5.4.3 Digital interfaces . 17
5.5 Voyage data recorder interface . 18
6 Test conditions, power sources and ambient temperatures . 18
6.1 Test conditions . 18
6.2 Test power source . 18
6.3 Normal test conditions . 18
6.3.1 Normal temperature and humidity . 18
6.3.2 Normal power source voltage . 18
6.3.2.1 Mains powered equipment . 18
6.3.2.2 Battery powered equipment . 19
6.3.2.3 Other power sources . 19
6.4 Extreme test conditions . 19
6.4.1 Extreme temperatures . 19
6.4.2 Extreme values of power source voltage . 19
6.4.2.1 Mains powered equipment . 19
6.4.2.2 Battery powered equipment . 19
6.4.2.3 Other power sources . 19
6.5 Procedure for tests at extreme temperatures . 19
7 General conditions of measurement . 19
7.1 Sequence of testing . 19
7.2 Test channels . 20
7.3 Squelch . 20
7.4 Arrangements for test signals applied to the receiver input . 20
ETSI
4 ETSI EN 301 925 V1.6.1 (2020-12)
7.5 Normal test modulation of the receiver wanted signal . 20
7.6 Arrangements for monitoring the receiver output . 20
7.7 Arrangements for test signals applied to the transmitter input . 21
7.8 Normal test modulation of the transmitter . 21
7.9 Arrangements for monitoring the transmitter output . 21
7.10 Arrangements for test of DSC . 21
7.11 Standard test signals for DSC . 21
7.12 Determination of symbol error ratio in the output of the receiver . 21
7.13 Reference bandwidths for spurious measurements . 22
7.14 Interpretation of the measurement results . 22
8 Performance checks . 23
8.1 Performance checks - introduction . 23
8.2 Performance check - transmitter frequency error . 23
8.3 Performance check - transmitter carrier power . 23
8.4 Performance check - transmitter audio frequency harmonic distortion of the emission . 23
8.5 Performance check - receiver sensitivity . 23
8.6 Performance check of DSC . 23
9 Environmental tests . 24
9.1 Procedure . 24
9.2 Vibration test . 24
9.2.1 Definition . 24
9.2.2 Method of measurement . 24
9.2.3 Requirement . 25
9.3 Temperature tests . 25
9.3.1 Introduction. 25
9.3.2 General procedure . 25
9.3.3 Dry heat . 25
9.3.3.1 Definition . 25
9.3.3.2 Method of measurement . 25
9.3.3.3 Requirement . 25
9.3.4 Damp heat . 25
9.3.4.1 Definition . 25
9.3.4.2 Method of measurement . 25
9.3.4.3 Requirement . 26
9.3.5 Low temperature cycle . 26
9.3.5.1 Definition . 26
9.3.5.2 Method of measurement . 26
9.3.5.3 Requirement . 26
10 Transmitter . 26
10.1 General conditions . 26
10.2 Frequency error . 26
10.2.1 Definition . 26
10.2.2 Method of measurement . 26
10.2.3 Limits . 27
10.3 Carrier power . 27
10.3.1 Definitions . 27
10.3.2 Method of measurement . 27
10.3.3 Limits . 27
10.3.3.1 General . 27
10.3.3.2 Normal test conditions limits . 27
10.3.3.3 Extreme test conditions limits . 27
10.4 Frequency deviation . 27
10.4.1 Definition . 27
10.4.2 Maximum permissible frequency deviation . 28
10.4.2.1 Method of measurement . 28
10.4.2.2 Limits . 28
10.4.3 Reduction of frequency deviation at modulation frequencies above 3 kHz . 28
10.4.3.1 Method of measurement . 28
10.4.3.2 Limits . 28
10.5 Sensitivity of the modulator including the microphone . 29
ETSI
5 ETSI EN 301 925 V1.6.1 (2020-12)
10.5.1 Definition . 29
10.5.2 Method of measurement . 29
10.5.3 Limits . 29
10.6 Audio frequency response . 29
10.6.1 Definition . 29
10.6.2 Method of measurement . 30
10.6.3 Limits . 30
10.7 Audio frequency harmonic distortion of the emission. 30
10.7.1 Definition . 30
10.7.2 Method of measurement . 31
10.7.3 Limits . 31
10.8 Adjacent channel power . 31
10.8.1 Definition . 31
10.8.2 Method of measurement . 31
10.8.3 Limits . 32
10.9 Conducted spurious emissions conveyed to the antenna . 32
10.9.1 Definition . 32
10.9.2 Method of measurement . 32
10.9.3 Limit . 32
10.10 Residual modulation of the transmitter . 32
10.10.1 Definition . 32
10.10.2 Method of measurement . 32
10.10.3 Limit . 33
10.11 Transient frequency behaviour of the transmitter . 33
10.11.1 Definition . 33
10.11.2 Method of measurement . 33
10.11.3 Limits . 34
10.12 Radiated spurious emission . 36
10.12.1 Definition . 36
10.12.2 Method of measurement . 36
10.12.3 Limits . 37
11 Transmitter with DSC encoder . 37
11.1 General . 37
11.2 Frequency error (carrier) . 37
11.2.1 Definition . 37
11.2.2 Method of measurement . 37
11.2.3 Limits . 38
11.3 Frequency error (demodulated signal) . 38
11.3.1 Definition . 38
11.3.2 Method of measurement . 38
11.3.3 Limits . 38
11.4 Carrier Power . 38
11.4.1 Definition . 38
11.4.2 Method of measurement . 38
11.4.3 Limits . 38
11.4.3.1 Normal test conditions . 38
11.4.3.2 Extreme test conditions . 39
11.5 Modulation index . 39
11.5.1 Definition . 39
11.5.2 Method of measurement . 39
11.5.3 Limits . 39
11.6 Modulation rate . 39
11.6.1 Definition . 39
11.6.2 Method of measurement . 39
11.6.3 Limits . 39
11.7 Residual modulation . 39
11.7.1 Definition . 39
11.7.2 Method of measurement . 39
11.7.3 Limits . 40
11.8 Modulator attack time . 40
11.8.1 Definition . 40
ETSI
6 ETSI EN 301 925 V1.6.1 (2020-12)
11.8.2 Method of measurement . 40
11.8.3 Limit . 40
11.9 Adjacent channel power . 40
11.9.1 Definition . 40
11.9.2 Method of measurement . 40
11.9.3 Limits . 41
11.10 Conducted spurious emissions . 41
11.11 Testing of free channel transmission on DSC channel 70 . 41
11.11.1 Definition . 41
11.11.2 Method of measurement . 41
11.11.3 Requirement . 41
11.12 Generated DSC call sequences . 42
12 Receiver . 42
12.1 Harmonic distortion and rated audio output power . 42
12.1.1 Definition . 42
12.1.2 Methods of measurement . 42
12.1.3 Limits . 42
12.2 Audio frequency response . 42
12.2.1 Definition . 42
12.2.2 Method of measurement . 43
12.2.3 Limits . 43
12.3 Maximum usable sensitivity . 44
12.3.1 Definition . 44
12.3.2 Method of measurement . 44
12.3.3 Limits . 44
12.4 Amplitude characteristic of the receiver . 44
12.4.1 Definition . 44
12.4.2 Method of measurement . 44
12.4.3 Limits . 44
12.5 Co-channel rejection. 45
12.5.1 Definition . 45
12.5.2 Method of measurement . 45
12.5.3 Limit . 45
12.6 Adjacent channel selectivity . 45
12.6.1 Definition . 45
12.6.2 Method of measurement . 45
12.6.3 Limits . 46
12.7 Spurious response rejection . 46
12.7.1 Definition . 46
12.7.2 Method of measurement . 46
12.7.2.1 Introduction to the method of measurement . 46
12.7.2.2 Method of search over the "limited frequency range" . 47
12.7.2.3 Method of measurement . 47
12.7.3 Limit . 47
12.8 Intermodulation response . 47
12.8.1 Definition . 47
12.8.2 Method of measurement . 48
12.8.3 Limit . 48
12.9 Blocking or desensitization . 48
12.9.1 Definition . 48
12.9.2 Method of measurement . 48
12.9.3 Limit . 48
12.10 Conducted spurious emissions . 49
12.10.1 Definition . 49
12.10.2 Method of measurement . 49
12.10.3 Limit . 49
12.11 Receiver noise and hum level . 49
12.11.1 Definition . 49
12.11.2 Method of measurement . 49
12.11.3 Limit . 49
12.12 Squelch operation . 50
ETSI
7 ETSI EN 301 925 V1.6.1 (2020-12)
12.12.1 Description . 50
12.12.2 Squelch audio muting . 50
12.12.2.1 Definition . 50
12.12.2.2 Method of measurement . 50
12.12.2.3 Limits . 50
12.12.3 Squelch operating level . 50
12.12.3.1 Definition . 50
12.12.3.2 Method of measurement . 50
12.12.3.3 Limits . 50
12.12.4 Squelch hysteresis . 51
12.12.4.1 Definition . 51
12.12.4.2 Method of measurement . 51
12.12.4.3 Limit . 51
12.13 Multiple watch characteristics . 51
12.13.1 Definitions . 51
12.13.2 Method of measurement . 51
12.13.3 Limits . 52
12.14 Radiated spurious emissions. 52
12.14.1 Definition . 52
12.14.2 Method of measurement . 52
12.14.3 Limits . 53
13 Receiver with a DSC decoder . 53
14 Duplex operation . 53
14.1 Introduction .
...

SLOVENSKI STANDARD
01-februar-2021
Radiotelefonski oddajniki in sprejemniki za pomorske mobilne storitve, ki delujejo
v pasovih VHF - Tehnične karakteristike in merilne metode
Radiotelephone transmitters and receivers for the maritime mobile service operating in
VHF bands - Technical characteristics and methods of measurement
Ta slovenski standard je istoveten z: ETSI EN 301 925 V1.6.1 (2020-12)
ICS:
33.060.20 Sprejemna in oddajna Receiving and transmitting
oprema equipment
47.020.70 Navigacijska in krmilna Navigation and control
oprema equipment
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
Radiotelephone transmitters and receivers for
the maritime mobile service operating in VHF bands;
Technical characteristics and methods of measurement

2 ETSI EN 301 925 V1.6.1 (2020-12)

Reference
REN/ERM-TGMAR-607
Keywords
EMC, GMDSS, maritime, radio, telephony, VHF
ETSI
650 Route des Lucioles
F-06921 Sophia Antipolis Cedex - FRANCE

Tel.: +33 4 92 94 42 00  Fax: +33 4 93 65 47 16

Siret N° 348 623 562 00017 - NAF 742 C
Association à but non lucratif enregistrée à la
Sous-Préfecture de Grasse (06) N° 7803/88

Important notice
The present document can be downloaded from:
http://www.etsi.org/standards-search
The present document may be made available in electronic versions and/or in print. The content of any electronic and/or
print versions of the present document shall not be modified without the prior written authorization of ETSI. In case of any
existing or perceived difference in contents between such versions and/or in print, the prevailing version of an ETSI
deliverable is the one made publicly available in PDF format at www.etsi.org/deliver.
Users of the present document should be aware that the document may be subject to revision or change of status.
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ETSI
3 ETSI EN 301 925 V1.6.1 (2020-12)
Contents
Intellectual Property Rights . 8
Foreword . 8
Modal verbs terminology . 8
1 Scope . 9
2 References . 9
2.1 Normative references . 9
2.2 Informative references . 10
3 Definition of terms, symbols and abbreviations . 11
3.1 Terms . 11
3.2 Symbols . 12
3.3 Abbreviations . 12
4 General requirements . 13
4.1 Construction . 13
4.2 DSC operation . 13
4.3 Controls and indicators . 14
4.4 Handset and loudspeaker . 14
4.5 Safety precautions . 15
4.6 Labelling. 15
4.7 Warm up . 15
4.8 Audio Processing . 15
5 Technical requirements . 16
5.1 Switching time . 16
5.2 Class of emission and modulation characteristics . 16
5.3 Multiple watch facilities . 16
5.3.1 Additional performance standards . 16
5.3.2 Scanning characteristics . 17
5.4 Interfaces . 17
5.4.1 General . 17
5.4.2 Audio frequency . 17
5.4.3 Digital interfaces . 17
5.5 Voyage data recorder interface . 18
6 Test conditions, power sources and ambient temperatures . 18
6.1 Test conditions . 18
6.2 Test power source . 18
6.3 Normal test conditions . 18
6.3.1 Normal temperature and humidity . 18
6.3.2 Normal power source voltage . 18
6.3.2.1 Mains powered equipment . 18
6.3.2.2 Battery powered equipment . 19
6.3.2.3 Other power sources . 19
6.4 Extreme test conditions . 19
6.4.1 Extreme temperatures . 19
6.4.2 Extreme values of power source voltage . 19
6.4.2.1 Mains powered equipment . 19
6.4.2.2 Battery powered equipment . 19
6.4.2.3 Other power sources . 19
6.5 Procedure for tests at extreme temperatures . 19
7 General conditions of measurement . 19
7.1 Sequence of testing . 19
7.2 Test channels . 20
7.3 Squelch . 20
7.4 Arrangements for test signals applied to the receiver input . 20
ETSI
4 ETSI EN 301 925 V1.6.1 (2020-12)
7.5 Normal test modulation of the receiver wanted signal . 20
7.6 Arrangements for monitoring the receiver output . 20
7.7 Arrangements for test signals applied to the transmitter input . 21
7.8 Normal test modulation of the transmitter . 21
7.9 Arrangements for monitoring the transmitter output . 21
7.10 Arrangements for test of DSC . 21
7.11 Standard test signals for DSC . 21
7.12 Determination of symbol error ratio in the output of the receiver . 21
7.13 Reference bandwidths for spurious measurements . 22
7.14 Interpretation of the measurement results . 22
8 Performance checks . 23
8.1 Performance checks - introduction . 23
8.2 Performance check - transmitter frequency error . 23
8.3 Performance check - transmitter carrier power . 23
8.4 Performance check - transmitter audio frequency harmonic distortion of the emission . 23
8.5 Performance check - receiver sensitivity . 23
8.6 Performance check of DSC . 23
9 Environmental tests . 24
9.1 Procedure . 24
9.2 Vibration test . 24
9.2.1 Definition . 24
9.2.2 Method of measurement . 24
9.2.3 Requirement . 25
9.3 Temperature tests . 25
9.3.1 Introduction. 25
9.3.2 General procedure . 25
9.3.3 Dry heat . 25
9.3.3.1 Definition . 25
9.3.3.2 Method of measurement . 25
9.3.3.3 Requirement . 25
9.3.4 Damp heat . 25
9.3.4.1 Definition . 25
9.3.4.2 Method of measurement . 25
9.3.4.3 Requirement . 26
9.3.5 Low temperature cycle . 26
9.3.5.1 Definition . 26
9.3.5.2 Method of measurement . 26
9.3.5.3 Requirement . 26
10 Transmitter . 26
10.1 General conditions . 26
10.2 Frequency error . 26
10.2.1 Definition . 26
10.2.2 Method of measurement . 26
10.2.3 Limits . 27
10.3 Carrier power . 27
10.3.1 Definitions . 27
10.3.2 Method of measurement . 27
10.3.3 Limits . 27
10.3.3.1 General . 27
10.3.3.2 Normal test conditions limits . 27
10.3.3.3 Extreme test conditions limits . 27
10.4 Frequency deviation . 27
10.4.1 Definition . 27
10.4.2 Maximum permissible frequency deviation . 28
10.4.2.1 Method of measurement . 28
10.4.2.2 Limits . 28
10.4.3 Reduction of frequency deviation at modulation frequencies above 3 kHz . 28
10.4.3.1 Method of measurement . 28
10.4.3.2 Limits . 28
10.5 Sensitivity of the modulator including the microphone . 29
ETSI
5 ETSI EN 301 925 V1.6.1 (2020-12)
10.5.1 Definition . 29
10.5.2 Method of measurement . 29
10.5.3 Limits . 29
10.6 Audio frequency response . 29
10.6.1 Definition . 29
10.6.2 Method of measurement . 30
10.6.3 Limits . 30
10.7 Audio frequency harmonic distortion of the emission. 30
10.7.1 Definition . 30
10.7.2 Method of measurement . 31
10.7.3 Limits . 31
10.8 Adjacent channel power . 31
10.8.1 Definition . 31
10.8.2 Method of measurement . 31
10.8.3 Limits . 32
10.9 Conducted spurious emissions conveyed to the antenna . 32
10.9.1 Definition . 32
10.9.2 Method of measurement . 32
10.9.3 Limit . 32
10.10 Residual modulation of the transmitter . 32
10.10.1 Definition . 32
10.10.2 Method of measurement . 32
10.10.3 Limit . 33
10.11 Transient frequency behaviour of the transmitter . 33
10.11.1 Definition . 33
10.11.2 Method of measurement . 33
10.11.3 Limits . 34
10.12 Radiated spurious emission . 36
10.12.1 Definition . 36
10.12.2 Method of measurement . 36
10.12.3 Limits . 37
11 Transmitter with DSC encoder . 37
11.1 General . 37
11.2 Frequency error (carrier) . 37
11.2.1 Definition . 37
11.2.2 Method of measurement . 37
11.2.3 Limits . 38
11.3 Frequency error (demodulated signal) . 38
11.3.1 Definition . 38
11.3.2 Method of measurement . 38
11.3.3 Limits . 38
11.4 Carrier Power . 38
11.4.1 Definition . 38
11.4.2 Method of measurement . 38
11.4.3 Limits . 38
11.4.3.1 Normal test conditions . 38
11.4.3.2 Extreme test conditions . 39
11.5 Modulation index . 39
11.5.1 Definition . 39
11.5.2 Method of measurement . 39
11.5.3 Limits . 39
11.6 Modulation rate . 39
11.6.1 Definition . 39
11.6.2 Method of measurement . 39
11.6.3 Limits . 39
11.7 Residual modulation . 39
11.7.1 Definition . 39
11.7.2 Method of measurement . 39
11.7.3 Limits . 40
11.8 Modulator attack time . 40
11.8.1 Definition . 40
ETSI
6 ETSI EN 301 925 V1.6.1 (2020-12)
11.8.2 Method of measurement . 40
11.8.3 Limit . 40
11.9 Adjacent channel power . 40
11.9.1 Definition . 40
11.9.2 Method of measurement . 40
11.9.3 Limits . 41
11.10 Conducted spurious emissions . 41
11.11 Testing of free channel transmission on DSC channel 70 . 41
11.11.1 Definition . 41
11.11.2 Method of measurement . 41
11.11.3 Requirement . 41
11.12 Generated DSC call sequences . 42
12 Receiver . 42
12.1 Harmonic distortion and rated audio output power . 42
12.1.1 Definition . 42
12.1.2 Methods of measurement . 42
12.1.3 Limits . 42
12.2 Audio frequency response . 42
12.2.1 Definition . 42
12.2.2 Method of measurement . 43
12.2.3 Limits . 43
12.3 Maximum usable sensitivity . 44
12.3.1 Definition . 44
12.3.2 Method of measurement . 44
12.3.3 Limits . 44
12.4 Amplitude characteristic of the receiver . 44
12.4.1 Definition . 44
12.4.2 Method of measurement . 44
12.4.3 Limits . 44
12.5 Co-channel rejection. 45
12.5.1 Definition . 45
12.5.2 Method of measurement . 45
12.5.3 Limit . 45
12.6 Adjacent channel selectivity . 45
12.6.1 Definition . 45
12.6.2 Method of measurement . 45
12.6.3 Limits . 46
12.7 Spurious response rejection . 46
12.7.1 Definition . 46
12.7.2 Method of measurement . 46
12.7.2.1 Introduction to the method of measurement . 46
12.7.2.2 Method of search over the "limited frequency range" . 47
12.7.2.3 Method of measurement . 47
12.7.3 Limit . 47
12.8 Intermodulation response . 47
12.8.1 Definition . 47
12.8.2 Method of measurement . 48
12.8.3 Limit . 48
12.9 Blocking or desensitization . 48
12.9.1 Definition . 48
12.9.2 Method of measurement . 48
12.9.3 Limit . 48
12.10 Conducted spurious emissions . 49
12.10.1 Definition . 49
12.10.2 Method of measurement . 49
12.10.3 Limit . 49
12.11 Receiver noise and hum level . 49
12.11.1 Definition . 49
12.11.2 Method of measurement . 49
12.11.3 Limit . 49
12.12 Squelch operation . 50
ETSI
7 ETSI EN 301 925 V1.6.1 (2020-12)
12.12.1 Description . 50
12.12.2 Squelch audio muting . 50
12.12.2.1 Definition . 50
12.12.2.2 Method of measurement . 50
12.12.2.3 Limits . 50
12.12.3 Squelch operating level . 50
12.12.3.1 Definition . 50
12.12.3.2 Method of measurement . 50
12.12.3.3 Limits . 50
12.12.4 Squelch hysteresis . 51
12.12.4.1 Definition . 51
12.12.4.2 Method of measurement . 51
12.12.4.3 Limit . 51
12.13 Multiple watch characteristics . 51
12.13.1 Definitions . 51
12.13.2 Method of measurement . 51
12.13.3 Limits .
...