SIST EN 60315-4:1999
(Main)Methods of measurement on radio receivers for various classes of emission -- Part 4: Receivers for frequency-modulated sound broadcasting emissions
Methods of measurement on radio receivers for various classes of emission -- Part 4: Receivers for frequency-modulated sound broadcasting emissions
Applies to radio receives and tuners for the reception of frequency- modulated sound-broadcasting emissions with rated maximum system deviations of ±75 kHz and ±50 kHz in ITU Band 8. Deals mainly with methods of measurement using radiofrequency signals applied to the antenna terminals of the receiver.
Meßverfahren für Funkempfänger für verschiedene Sendearten -- Teil 4: Empfänger für frequenzmodulierte Ton-Rundfunksendungen
Méthodes de mesure applicables aux récepteurs radioélectriques pour diverses classes d'émission -- Partie 4: Récepteurs pour émissions de radiodiffusion en modulation de fréquence
S'applique aux récepteurs radio et aux syntoniseurs destinés à la réception des émissions de radiodiffusion en modulation de fréquence, ayant des excursions maximales nominales du système de ±75 kHz et de ±50 dans la bande 8 de l'UIT. Traite principalement des méthodes de mesure utilisant des signaux RF appliqués aux bornes d'antenne du récepteur.
Methods of measurement on radio receivers for various classes of emission -- Part 4: Receivers for frequency-modulated sound broadcasting emissions (IEC 60315-4:1997)
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN 60315-4:1999
01-april-1999
Methods of measurement on radio receivers for various classes of emission -- Part
4: Receivers for frequency-modulated sound broadcasting emissions (IEC 60315-
4:1997)
Methods of measurement on radio receivers for various classes of emission -- Part 4:
Receivers for frequency-modulated sound broadcasting emissions
Meßverfahren für Funkempfänger für verschiedene Sendearten -- Teil 4: Empfänger für
frequenzmodulierte Ton-Rundfunksendungen
Méthodes de mesure applicables aux récepteurs radioélectriques pour diverses classes
d'émission -- Partie 4: Récepteurs pour émissions de radiodiffusion en modulation de
fréquence
Ta slovenski standard je istoveten z: EN 60315-4:1998
ICS:
33.160.20 Radijski sprejemniki Radio receivers
SIST EN 60315-4:1999 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN 60315-4:1999
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SIST EN 60315-4:1999
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SIST EN 60315-4:1999
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SIST EN 60315-4:1999
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SIST EN 60315-4:1999
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SIST EN 60315-4:1999
NORME
CEI
INTERNATIONALE
IEC
60315-4
INTERNATIONAL
Deuxième édition
STANDARD
Second edition
1997-11
Méthodes de mesure applicables aux récepteurs
radioélectriques pour diverses classes d'émission –
Partie 4:
Récepteurs pour émissions de radiodiffusion
en modulation de fréquence
Methods of measurement on radio receivers for
various classes of emission –
Part 4:
Receivers for frequency-modulated
sound broadcasting emissions
IEC 1997 Droits de reproduction réservés Copyright - all rights reserved
Aucune partie de cette publication ne peut être reproduite ni No part of this publication may be reproduced or utilized in
utilisée sous quelque forme que ce soit et par aucun any form or by any means, electronic or mechanical,
procédé, électronique ou mécanique, y compris la photo- including photocopying and microfilm, without permission in
copie et les microfilms, sans l'accord écrit de l'éditeur. writing from the publisher.
International Electrotechnical Commission 3, rue de Varembé Geneva, Switzerland
Telefax: +41 22 919 0300 e-mail: inmail@iec.ch IEC web site http: //www.iec.ch
CODE PRIX
Commission Electrotechnique Internationale
PRICE CODE XB
International Electrotechnical Commission
Pour prix, voir catalogue en vigueur
For price, see current catalogue
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SIST EN 60315-4:1999
60315-4 © IEC:1997 – 3 –
CONTENTS
Page
FOREWORD . 9
Clause
1 General. 13
1.1 Scope. 13
1.2 Normative references. 13
1.3 Definitions. 15
1.4 Standard measuring conditions . 17
1.5 General notes on measurements. 27
2 Sensitivity and internal noise. 33
2.1 Explanation of terms . 33
2.2 Signal-to-noise ratio (weighted and unweighted) and SINAD . 33
2.3 Noise-limited sensitivity. 35
2.4 Gain-limited sensitivity. 37
2.5 Usable sensitivity. 37
2.6 Deviation sensitivity. 39
2.7 Input-output characteristics. 39
3 Rejection of unwanted signals. 41
3.1 Capture ratio. 41
3.2 Selectivity and nearby channel rejection (two-signal) . 43
3.3 Rejection of intermediate and image frequencies, and spurious responses . 47
3.4 Suppression of amplitude modulation . 53
3.5 Rejection of r.f. signal intermodulation products . 55
3.6 Tuning and automatic frequency control (AFC) characteristics . 63
4 Interference due to internal sources . 65
4.1 Single-signal whistles. 65
4.2 Modulation hum (interference at power supply frequency). 65
4.3 Unwanted self-oscillations. 67
4.4 Acoustic feedback. 69
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Page
5 Overall audio-frequency characteristics. 69
5.1 Fidelity. 69
5.2 Harmonic distortion. 71
5.3 Intermodulation distortion. 79
5.4 Inter-channel characteristics. 81
5.5 Characteristics of the volume control. 83
5.6 Residual output. 85
5.7 Crosstalk attenuation. 85
5.8 Overall audio-frequency response . 87
6 Effect of additional modulations of the input signal . 89
6.1 Rejection of signals in the ranges 16 kHz to 22 kHz and 54 kHz to 99 kHz. 89
6.2 Rejection of signals in the range 62 kHz to 73 kHz (SCA rejection) . 89
6.3 Measurement of interference caused by RDS signals . 89
6.4 Suppression of the fundamental, harmonics and sidebands of the subcarrier
and the pilot-tone signal . 91
6.5 Suppression of interference due to adjacent channel signals with a
stereophonic receiver using the pilot-tone system. 93
7 Sensitivity, antenna gain and directional response of receivers using rod, telescopic
or built-in antennas . 93
7.1 Introduction. 93
7.2 Method of measurement of sensitivity and antenna gain for a receiver using
a rod or telescopic antenna by the absorbing clamp described in CISPR 16-1. 93
8 Characteristics whose methods of measurement are specified in IEC 60315-1 . 95
8.1 Introduction. 95
8.2 List of characteristics and cross-references. 95
Figures
1 Frequency response limits of band-pass filter 200 Hz to 15 kHz . 97
2 Frequency response limits of band-pass filter 22,4 Hz to 15 kHz . 99
3 Frequency response limits of band-pass filter 200 Hz to 1,5 kHz . 99
4 Frequency response limits of the 1 kHz band-elimination filter. 101
5 Weighting filter for converting white noise into special coloured noise for
selectivity measurements. 101
6 Arrangement for various measurements with two r.f. input signals . 103
7 Antenna substitution networks for injecting one or two signals, for 50 Ω signal
generators and 75 Ω unbalanced and 300 Ω balanced receiver inputs . 105
8 Arrangement for various measurements with one r.f. input signal . 107
9 Signal-to-noise ratio. 109
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Page
10 Noise-limited sensitivity as a function of signal frequency. 109
11 Gain-limited sensitivity as a function of signal frequency . 111
12 Output/input characteristics and noise output curves showing terms defined in 1.3 . 113
13 Capture ratio . 115
14 Selectivity curves. 117
15 Image and intermediate frequency rejection ratios. 119
16 Spurious responses at a tuning frequency of 94 MHz (single signal method). 121
17 Arrangement for measuring rejection of unwanted signals simulating cable reception,
using sinusoidal modulation . 123
18 Arrangement for various measurements using three r.f. input signals . 125
19 Tuning characteristics. 127
20 Tuning characteristics obtained by measuring the local oscillator frequency . 127
21 Measurement of acoustic feedback . 129
22 Arrangement for measuring fidelity. 129
23 Overall total harmonic distortion as a function of a.f. output power . 131
24 Distortion-limited output power as a function of modulation frequency . 131
25 Total harmonic distortion as a function of r.f. input signal level . 133
26 Total harmonic distortion as a function of the deviation . 133
27 Variation of distortion with detuning. 135
28 Total harmonic distortion as a function of the a.f. modulation frequency . 135
29 Cross-intermodulation between the channels of a stereo receiver (pilot-tone system) . 137
A.1 Example of a passive 1 kHz band-elimination filter capable of meeting the limits
shown in figure 4 . 139
D.1 Arrangement for r.f. signal injection into the antenna with an absorbing clamp. 147
D.2 Correction curves for the insertion loss of the absorbing clamp . 147
Annexes
A Example of a 1 kHz band-elimination filter. 139
B Standard deviations for supplementary services. 141
C Measurement of crosstalk between stereo channels. 143
D Characteristics of rod and telescopic antennas (under consideration) . 145
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SIST EN 60315-4:1999
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INTERNATIONAL ELECTROTECHNICAL COMMISSION
_________
METHODS OF MEASUREMENT ON RADIO RECEIVERS FOR
VARIOUS CLASSES OF EMISSION –
Part 4: Receivers for frequency-modulated
sound broadcasting emissions
FOREWORD
1) The IEC (International Electrotechnical Commission) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of the IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, the IEC publishes International Standards. Their preparation is
entrusted to technical committees; any IEC National Committee interested in the subject dealt with may
participate in this preparatory work. International, governmental and non-governmental organizations liaising
with the IEC also participate in this preparation. The IEC collaborates closely with the International Organization
for Standardization (ISO) in accordance with conditions determined by agreement between the two
organizations.
2) The formal decisions or agreements of the IEC on technical matters express, as nearly as possible, an
international consensus of opinion on the relevant subjects since each technical committee has representation
from all interested National Committees.
3) The documents produced have the form of recommendations for international use and are published in the form
of standards, technical reports or guides and they are accepted by the National Committees in that sense.
4) In order to promote international unification, IEC National Committees undertake to apply IEC International
Standards transparently to the maximum extent possible in their national and regional standards. Any
divergence between the IEC Standard and the corresponding national or regional standard shall be clearly
indicated in the latter.
5) The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with one of its standards.
6) Attention is drawn to the possibility that some of the elements of this International Standard may be the subject
of patent rights. The IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60315-4 has been prepared by IEC subcommittee 100A: Multimedia
end-user equipment, of IEC technical committee 100: Audio, video and multimedia systems and
equipment.
This second edition cancels and replaces the first edition published in 1982 and constitutes a
technical revision.
This part of IEC 60315 shall be read in conjunction with IEC 60315-1.
The text of this standard is based on the following documents:
FDIS Report on voting
100A/58/FDIS 100A/60/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
Annexes A, B, C and D are for information only.
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IEC 60315 consists of the following parts under the general title: Methods of measurement on
radio receivers for various classes of emission:
– Part 1: 1988, General considerations and methods of measurement, including audio-
frequency measurements
– Part 3: 1989, Receivers for amplitude – modulated sound broadcasting emissions
– Part 4: 1997, Receivers for frequency – modulated sound broadcasting emissions
– Part 5: 1971, Specialized radio-frequency measurements – Measurement on frequency-
modulated receivers of the response to impulsive interference
– Part 6: 1991, General purpose communication receivers
– Part 7: 1995, Methods of measurement on digital satellite radio (DSR) receivers
– Part 8: 1975, Radio-frequency measurements on professional receivers for frequency-
modulated telegraphy systems
– Part 9: 1996, Measurement of the characteristics relevant to radio data system (RDS)
reception
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METHODS OF MEASUREMENT ON RADIO RECEIVERS FOR
VARIOUS CLASSES OF EMISSION –
Part 4: Receivers for frequency-modulated
sound broadcasting emissions
1 General
1.1 Scope
This part of IEC 60315 applies to radio receivers and tuners for the reception of frequency-
modulated sound-broadcasting emissions with rated maximum system deviations of ±75 kHz
and ±50 kHz in ITU Band 8. It deals mainly with methods of measurement using radio-
frequency signals applied to the antenna terminals of the receiver. The measurements and
specified conditions of test are selected to permit the comparison of results obtained by
different observers and on other receivers. Performance requirements are not specified in
this standard.
Radiation and immunity tests and requirements are not included since these are described in
CISPR 13 and CISPR 20.
1.2 Normative references
The following normative documents contain provisions which, through reference in this text,
constitute provisions of this part of IEC 60315. At the time of publication, the editions indicated
were valid. All normative documents are subject to revision, and parties to agreements based
on this part of IEC 60315 are encouraged to investigate the possibility of applying the most
recent editions of the normative documents indicated below. Members of IEC and ISO maintain
registers of currently valid International Standards.
IEC 60098: 1987, Analogue audio disk records and reproducing equipment
IEC 60268-1: 1985, Sound system equipment – Part 1: General
IEC 60268-3: 1988, Sound system equipment – Part 3: Amplifiers
IEC 60315-1: 1988, Methods of measurement on radio receivers for various classes of
emission – Part 1: General considerations and methods of measurement, including audio-
frequency measurements
IEC 60315-3: 1989, Methods of measurement on radio receivers for various classes of
emission – Part 3: Receiver for amplitude-modulated sound-broadcasting emissions
IEC 60315-7: 1995, Methods of measurement on radio receivers for various classes of
emission – Part 7: Methods of measurement on digital satellite radio (DSR) receivers
IEC 60315-9: 1996, Methods of measurement on radio receivers for various class of emission –
Part 9: Measurement of the characteristics relevant to Radio Data System (RDS) reception
IEC 60651: 1979, Sound level meters
IEC 61260: 1995, Electroacoustics – Octave-band and fractional-octave-band filters
CISPR 16-1: 1993, Specification for radio disturbance and immunity measuring apparatus and
methods – Part 1: Radio disturbance and immunity measuring apparatus
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CISPR 20: 1996, Limits and methods of measurement of immunity characteristics of sound and
television broadcast receivers and associated equipment
ITU-R Recommendation 468-4: 1990: Measurement of audio-frequency
ITU-R Recommendation 559-2: 1990: Objective measurement of radio-frequency protection
ratios in LF, MF and HF broadcasting
1.3 Definitions
For the purposes of this part of IEC 60315, the following definitions apply.
1.3.1
carrier frequency
the mean value of the instantaneous frequency or the frequency generated in the absence of
modulation. With a perfect modulation system in which no d.c. component and no non-linear
distortion are involved, the two values are the same
1.3.2
instantaneous frequency deviation
the difference between the instantaneous frequency of the modulated radio-frequency signal
and the carrier frequency
1.3.3
peak frequency deviation
the peak value of the instantaneous frequency deviation
1.3.4
peak-to-peak deviation
twice the peak frequency deviation
NOTE 1 – To avoid confusion between "peak frequency deviation" and "peak-to-peak frequency deviation", peak-to-
peak deviation is expressed as, for example, ± 50 kHz.
NOTE 2 – "Peak-to-peak frequency deviation" is generally abbreviated to "deviation" in this standard.
1.3.5
rated maximum system deviation
the maximum peak-to-peak frequency deviation (see 1.3.4) specified for the system under
consideration
1.3.6
modulation factor
the ratio of the peak-to-peak deviation of the signal to the rated maximum system deviation,
usually expressed as a percentage
NOTE – This definition arises by direct analogy with the case of amplitude modulation.
1.3.7
–3 dB limiting level
the input signal level at which the audio-frequency output voltage level is 3 dB below the value
at a specified high r.f. input signal level, preferably 80 dB(fW)
1.3.8
amplification reserve
the attenuation in decibels of the volume control when adjusted to produce rated (distortion-limited)
output voltage or power, with a specified high r.f. input signal level, preferably 80 dB(fW)
NOTE – This characteristic is undefined for a receiver or tuner without a volume control.
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1.3.9
deviation sensitivity
the value of deviation required to produce rated (distortion-limited) output voltage or power
with the volume control set at maximum and a specified high r.f. input signal level, preferably
80 dB(fW)
1.3.10
ultimate signal-to-noise ratio
the value of signal-to-noise ratio for r.f. input signal levels sufficiently high that no further
increase in signal-to-noise ratio occurs when the input signal level is increased
1.3.11
stereo threshold
the r.f. input signal level at which the stereo decoder begins to operate
NOTE – A marked decrease in signal-to-noise ratio is usual at this signal level unless signal-strength dependent
cross-talk circuits are included.
1.3.12
stereo indicator threshold
the input signal level at which the visual indicator shows that the receiver is operating in the
stereo mode
NOTE – This level may or may not be identical to the stereo threshold.
1.3.13
muting threshold
the input signal level at which the muting circuits allow the a.f. output signal to appear at the
output terminals
NOTE – The threshold may be different for increasing and decreasing signal levels. This hysteresis is usually
intentional as it prevents unsatisfactory operation with r.f. input signals at or near the threshold level.
1.3.14
muting attenuation
the reduction in a.f. output, selectively measured at 1 kHz, due to an input signal modulated
at 1 kHz at rated maximum system deviation, when muting occurs
1.3.15
50 dB quieting sensitivity
the r.f. input signal level at which an increase in a.f. output of 50 dB occurs under defined
conditions (see 2.3) when the modulation is changed from none (except the pilot-tone if the
measurement is to be made in stereo mode) to the standard value of deviation (see 1.4.2.1)
1.4 Standard measuring conditions
1.4.1 Measurements at audio-frequency output terminals
1.4.1.1 Standard audio-frequency output level
Standard audio-frequency output level is the reference output level for audio-frequency
measurements and shall be 10 dB below the rated output voltage or power. Alternatively, a
stated value of output voltage or power selected from 500 mV, 1 W, 500 mW, 50 mW, 5 mW
or 1 mW may be used (see IEC 60315-1).
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1.4.1.2 Audio-frequency substitute load
The audio-frequency substitute load is a stated physical (usually resistive) impedance for
terminating audio-output terminals, (see IEC 60315-1).
1.4.1.3 Audio-frequency filters
When making measurements at audio-frequency output terminals, unless it is specifically
intended to measure low audio-frequency and ultrasonic components in the output voltage, it is
desirable to interpose a band-pass filter between the output terminals and the measuring
instrument. To allow the use of practicable impedances in this filter the substitute load shall be
connected directly to the audio-frequency output terminals. If the filter has significant insertion
loss this shall be allowed for when determining the results.
It is advisable to use the same filter for both monophonic and stereophonic receivers. This filter
prevents errors due to the presence of pilot-tone or subcarrier components in the receiver
output. The pass-band of this filter shall be 200 Hz to 15 kHz, for which frequencies the
attenuation relative to that at 1 kHz shall not exceed 3 dB. Below 200 Hz the attenuation slope
shall tend to at least 18 dB/octave. At 19 kHz the attenuation shall be at least 50 dB, and above
19 kHz it shall be at least 30 dB (see figure 1). This filter usually prevents the results of
measurements from being affected by hum.
Filters for octave and third-octave band measurements shall comply with the requirements
of IEC 61260.
Table 1 lists the audio-frequency filters which are used in measurements in this standard.
Table 1 – Audio-frequency filters
Type of filter Figure Reference Notes
200 Hz – 15 kHz band-pass 1 1.4.1.3 With 19 kHz notch
22,4 Hz – 15 kHz band-pass 2 2.2.1 With 19 kHz notch
200 Hz – 1,5 kHz band-pass 3 Figure 8 With 19 kHz notch
15 kHz low-pass None 1.4.2.3 60 dB/octave attenuation slope
1 kHz band-stop 4 Figure 8 See also annex A
1
1 kHz band-pass None Figure 6 / -octave: IEC 61260
3
A-weighting None Figure 8 See IEC 60651
Weighting filter for measurement Annex A of 2.2.1 Consistent with ITU-R
of noise IEC 60315-1 Recommendation 468-4
Weighting filter for coloured noise 5 1.4.2.3 Consistent with ITU-R
Recommendation 559-2
1.4.2 Radio-frequency signal(s)
1.4.2.1 Standard value of deviation
The standard value of deviation for measurements shall be the rated maximum system
deviation (RMSD) given in table 2. The deviation shall be stated with the results.
Measurements at lower deviations are useful in some cases: where these are carried out the
deviation used shall be stated with the results.
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Table 2 – Standard values of deviation
Mode/signal RMSD ±50 kHz RMSD ±75 kHz
Mono ±50 kHz ±75 kHz
Stereo ±45 kHz ±67,5 kHz
Pilot-tone ±4,5 kHz ±6,75 kHz
NOTE 1 – Where a single value for deviation is stated in the text, it applies to a system with RMSD = ±75 kHz.
For a system with RMSD = ±50 kHz, the stated value is reduced in proportion. In some cases, the value
for RMSD = ±50 kHz is given in parentheses: for example, (±50 kHz).
NOTE 2 – The deviations for supplementary services (such as SCA, RDS and ARI), which may vary in
different ITU regions or countries, are given in annex B.
1.4.2.2 Standard modulating frequency
The standard modulating frequency shall be the standard reference frequency (1 000 Hz).
When required, other frequencies may be chosen, if possible, from the one-third octave band
centre frequencies given in table I of IEC 60315-1.
1.4.2.3 Standard modulation using coloured noise
The noise weighting is chosen so that the spectrum of the noise resembles that of modern
(western European) dance music, which is a particularly critical form of modulation in the case
of adjacent channel interference.
The noise signal is obtained from a Gaussian white noise generator by passing the signal
through a weighting filter as specified in figure 5, followed by a low-pass filter with a cut-off
frequency of 15 kHz and a slope of 60 dB/octave, and then through a pre-emphasis network
(50 μs or 75 μs as appropriate).
The audio-frequency amplitude versus frequency characteristic of the modulation stage of the
signal generator should not vary by more than 2 dB up to the cut-off frequency of the low-pass
filter.
The accuracy of the measurement depends very much on the precision with which the
frequency deviation of the signal generators can be set; this is especially true for the unwanted
transmitter. The line-up procedure therefore should be carried out very carefully.
The deviation of the signal shall be adjusted by means of the arrangement shown in figure 6.
The meter V shall be a quasi-peak voltmeter (see annex A of IEC 60315-1). To obtain
1
the required deviation conditions, the switch S is placed in position 1 and the modulation
4
at 500 Hz from the audio-frequency generator adjusted to ±32 kHz (±21,3 kHz) deviation. The
meter reading is noted. The switch S is then placed in position 2 and the noise modulation
4
adjusted to give the same reading on the quasi-peak meter.
NOTE – The deviation with 500 Hz modulation should be checked with a deviation meter unless the deviation
meter, if any, included in the signal generator is known to be accurate.
1.4.2.4 Standard modulating signal
This is the base-band signal with standard modulating frequency (see 1.4.2.2) and standard
value of deviation (see 1.4.2.1). In case of stereophonic mode measurements, a pilot tone
signal with the standard deviation shall be included.
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