CISPR 20:2006

CISPR 20 ®
Edition 6.1 2013-10
CONSOLIDATED
VERSION
VERSION
CONSOLIDÉE
colour
inside
INTERNATIONAL SPECIAL COMMITTEE ON RADIO INTERFERENCE
COMITÉ INTERNATIONAL SPÉCIAL DES PERTURBATIONS RADIOÉLECTRIQUES

Sound and television broadcast receivers and associated equipment – Immunity
characteristics – Limits and methods of measurement

Récepteurs de radiodiffusion et de télévision et équipements associés –
Caractéristiques d’immunité – Limites et méthodes de mesure

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CISPR 20 ®
Edition 6.1 2013-10
CONSOLIDATED
VERSION
VERSION
CONSOLIDÉE
colour
inside
INTERNATIONAL SPECIAL COMMITTEE ON RADIO INTERFERENCE

COMITÉ INTERNATIONAL SPÉCIAL DES PERTURBATIONS RADIOÉLECTRIQUES

Sound and television broadcast receivers and associated equipment – Immunity

characteristics – Limits and methods of measurement

Récepteurs de radiodiffusion et de télévision et équipements associés –

Caractéristiques d’immunité – Limites et méthodes de mesure

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 33.100.20 ISBN 978-2-8322-1187-8

CISPR 20 ®
Edition 6.1 2013-10
REDLINE VERSION
VERSION REDLINE
colour
inside
INTERNATIONAL SPECIAL COMMITTEE ON RADIO INTERFERENCE
COMITÉ INTERNATIONAL SPÉCIAL DES PERTURBATIONS RADIOÉLECTRIQUES

Sound and television broadcast receivers and associated equipment – Immunity
characteristics – Limits and methods of measurement

Récepteurs de radiodiffusion et de télévision et équipements associés –
Caractéristiques d’immunité – Limites et méthodes de mesure

–   – CISPR 20  IEC:2006+A1:2013

CONTENTS
FOREWORD . 5

1 Scope and object . 7

2 Normative references . 8

3 Terms, definitions and abbreviations . 8

3.1 Terms and definitions . 8

3.2 Abbreviations . 11

4 Immunity requirements . 11
4.1 Performance criteria . 11
4.2 Applicability . 13
4.3 Immunity requirements for the antenna input connector . 14
4.4 Immunity requirements for audio connectors . 22
4.5 Immunity requirements for AC mains power connectors . 23
4.6 Requirements for immunity to RF voltages . 23
4.7 Immunity requirements for the enclosure port . 25
5 Immunity measurements . 29
5.1 General conditions during testing . 29
5.2 Performance assessment . 30
5.3 Measurement of input immunity . 31
5.4 Measurement of immunity to RF voltage (common mode) at antenna terminal . 33
5.5 Measurement of screening effectiveness . 35
5.6 Measurement of electrical transients . 36
5.7 Measurement of immunity to induced voltages . 36
5.8 Measurement of immunity from radiated fields . 39
5.9 Measurement of electrostatic discharge. 41
6 Interpretation of CISPR immunity limits . 42
6.1 Significance of a CISPR limit . 42
6.2 Compliance with limits on a statistical basis . 42

Annex A (normative) Specification of the test-TV-set . 51
Annex B (normative) Specification of filters and weighting network . 52
Annex C (normative)  Specification of coupling units and of low-pass filter . 54

Annex D (normative) Matching networks and mains stop filter . 60
Annex E (normative) Construction information for the open stripline and for the mains
and loudspeaker band-stop filter . 62
Annex F (normative) Calibration of the open stripline . 68
Annex G (normative) Ferrite core sizes and materials . 71
Annex H (informative) Frequency bands . 72
Annex I (normative)  Broadcast receivers for digital signals . 73
Annex J (informative)  Specification of the wanted signal . 77
Annex K (informative)  Objective evaluation of picture quality . 82

Bibliography . 86

CISPR 20  IEC:2006+A1:2013 – 3 –

Figure 1 – Examples of ports . 11

Figure 2 – Audio power output measurement . 43

Figure 3 – Measuring set-up for input immunity measurement of sound broadcast

receivers . . 43

Figure 4 – Measuring set-up for input immunity measurement of television receivers

and video tape equipment . 44

Figure 5 – General principle of the current injection method . 89

Figure 6 – Measurement principle for the immunity from conducted currents . 46

Figure 7 – Measuring set-up for the screening effectiveness . 47

Figure 8 – Measurement of immunity from induced voltages at mains input,
headphones, speakers, audio output, audio input . 48
Figure 9 – Example of the arrangement of an open stripline TEM device in combination
with absorbing plates inside a screened room with dimensions of 3 m x 3,5 m . 49
Figure 10 – Measurement of the immunity of broadcast receivers from radiated fields
in the frequency range 0,15 MHz to 150 MHz in an open stripline . 50
Figure 11 – Measurement of the immunity from RF e.m. field, keyed carrier, using a
dummy GSM portable telephone . 50
Figure B.1 – Band-pass filter 0,5 kHz to 3 kHz . 52
Figure C.1 – Coupling unit type AC (for coaxial antenna input) . 56
Figure C.2 – Coupling unit type MC (for mains lead) . 57
Figure C.3 – Coupling unit type LC (for loudspeaker leads) . 58
Figure C.4 – Coupling unit type Sr with load resistances . 58
Figure C.5 – Measuring set-up to check the insertion loss of the coupling units in the
frequency range 30 MHz to 150 MHz . 59
Figure D.1 – RC network for audio inputs (RC ) . 60
i
Figure D.2 – RC network for audio outputs (RC ) . 60
o
Figure D.3 – Mains stop filter (MSF) . 61
Figure E.1 – Open stripline TEM device, basic configuration with matching network
and terminating impedance . 62
Figure E.2 – Overview of an open stripline TEM device. 63
Figure E.3 – Constructional details of an open stripline, TEM device . 64
Figure E.4 – Supplementary constructional details of the open stripline TEM device . 65
Figure E.5 – Matching network MN . 65

Figure E.6 – Terminating impedance TI . 65
Figure E.7 – Band-stop filter type MBS circuit (for mains connection) . 66
Figure E.8 – Band-stop filter type LBS (for loudspeaker connection) . 67
Figure F.1 – Circuit arrangement for calibration of the measuring set-up . 69
Figure F.2 – Example of additional arrangement for enquiry of the calibration curve . 70
Figure F.3 – Calibration curve . 70
Figure K.1 – Measuring set-up for objective picture evaluation for EUT equipped with
a display . . 85
Figure K.2 – Measuring set-up for objective picture evaluation for EUT without a
display . 85

–   – CISPR 20  IEC:2006+A1:2013

Table 1 – Survey (non exhaustive) of receiver and associated equipment types,

including the appropriate parts of multifunction equipment . 9

Table 2 – Antenna port . 14

Table 3 – Limits of input immunity from unwanted signals outside the FM range (see

also 5.3.1.2 for the wanted signal) . 15

Table 4 – Limits of input immunity from unwanted signals inside the FM range (see

also 5.3.1.3 for the wanted signal) . 15

Table 5 – Limits of input immunity of television receivers for systems B, G and I . 17

Table 5a – Limits of input immunity of television receivers for system L . 18

Table 5b – Limits of input immunity of television receivers for systems D-SECAM, K-
SECAM (used in Russia). 18
Table 5c – Limits of input immunity of television receivers for systems PAL D/K (used
in central Europe) . 19
Table 5d – Limits of input immunity of television receivers for system M-NTSC with a
58,75 MHz IF video carrier (used in Japan) . 19
Table 6 – Limits of input immunity of television receivers . 20
Table 7 – Limits of input immunity of satellite television receivers . 20
Table 7a – Limits of input immunity of satellite television receivers (Used in Japan,
Korea) . 21
Table 8 – Limits of immunity to RF voltages (common mode) of antenna terminals . 21
Table 8a – Limits of screening effectiveness of the coaxial antenna terminals . 22
Table 9 – Loudspeakers/headphone output port . 22
Table 10 – Audio input/output port (excluding loudspeaker and headphone) . 23
Table 11 – Power input port . 23
Table 12 – Limits of immunity to RF voltages of mains, loudspeaker and headphone
terminals . 24
Table 13 – Limits of immunity to RF voltages of audio input and output terminals
(except loudspeaker and headphone terminals) . 24
Table 14 – Additional unwanted signal frequencies to be excluded in tests on sound
and television reception functions. . 25
Table 15 – Enclosure port . 25
Table 16 – Limits of immunity to ambient electromagnetic fields of FM and digital radio
reception functions of sound receivers . 26
Table 17 – Limits of immunity to ambient electromagnetic fields of television receivers
operating in the reception function . 27
Table 18 – Limits of immunity to ambient electromagnetic fields of video tape
equipment in the playback mode . 28
Table 19 – Limits of immunity to ambient electromagnetic fields of equipment with
audio or video functions . 28
Table 20 – Limits of immunity to ambient electromagnetic fields of camcorders in the
playback mode . 28
Table 21 – Function of the connections in Figure 8 . 37
Table 22 – Measurement conditions for the test of immunity from conducted voltages . 38
Table 23 – Measurement conditions for the test of immunity from radiated fields . 41
Table G.1 – Ferrite core sizes and materials . 71

CISPR 20  IEC:2006+A1:2013 – 5 –

INTERNATIONAL ELECTROTECHNICAL COMMISSION

INTERNATIONAL SPECIAL COMMITTEE ON RADIO INTERFERENCE

_____________
SOUND AND TELEVISION BROADCAST RECEIVERS

AND ASSOCIATED EQUIPMENT –
IMMUNITY CHARACTERISTICS –
LIMITS AND METHODS OF MEASUREMENT

FOREWORD
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patent rights. IEC shall not be held responsible for identifying any or all such patent rights.

This Consolidated version of CISPR 20 bears the edition number 6.1. It consists of the
sixth edition (2006) [documents CISPR/I/200/FDIS and CISPR/I/216/RVD] and its
amendment 1 (2013) [documents CISPR/I/444/FDIS and CISPR/I/460/RVD]. The technical
content is identical to the base edition and its amendment.
In this Redline version, a vertical line in the margin shows where the technical content
is modified by amendment 1. Additions and deletions are displayed in red, with
deletions being struck through. A separate Final version with all changes accepted is
available in this publication.
This publication has been prepared for user convenience.

–   – CISPR 20  IEC:2006+A1:2013

International Standard CISPR 20 has been prepared by CISPR, subcommittee I:
Electromagnetic compatibility of information technology equipment, multimedia equipment and

receivers.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.

The committee has decided that the contents of the base publication and its amendment will
remain unchanged until the stability date indicated on the IEC web site under

"http://webstore.iec.ch" in the data related to the specific publication. At this date, the

publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The “colour inside” logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct understanding
of its contents. Users should therefore print this publication using a colour printer.

CISPR 20  IEC:2006+A1:2013 – 7 –

SOUND AND TELEVISION BROADCAST RECEIVERS

AND ASSOCIATED EQUIPMENT –
IMMUNITY CHARACTERISTICS –
LIMITS AND METHODS OF MEASUREMENT

1 Scope and object
This standard for immunity requirements applies to television broadcast receivers, sound
broadcast receivers and associated equipment intended for use in the residential, commercial
and light industrial environment.
This standard describes the methods of measurement and specified limits applicable to sound
and television receivers and to associated equipment with regard to their immunity
characteristics to disturbing signals.
This standard is also applicable to the immunity of outdoor units of direct to home (DTH)
satellite receiving systems for individual reception.
NOTE 1 Receiving systems for collective reception, in particular cable distribution head ends (Community
Antenna Television, CATV) and community reception systems (Master Antenna Television, MATV) are covered by
IEC 60728-2.
NOTE 2 Broadcast receivers for digital signals are covered by Annex I and Annex J.
Immunity requirements are given in the frequency range 0 Hz to 400 GHz. Radio-frequency
tests outside the specified frequency bands or concerning other phenomena than given in this
standard are not required.
The objective of this standard is to define the immunity test requirements for equipment
defined in the scope in relation to continuous and transient, conducted and radiated
disturbances including electrostatic discharges.
These test requirements represent essential electromagnetic immunity requirements.
Test requirements are specified for each port (enclosure or connector) considered.
NOTE 3 This standard does not specify electrical safety requirements for equipment such as protection against
electric shocks, unsafe operation, insulation co-ordination and related dielectric tests.
NOTE 4 In special cases, situations will arise where the level of disturbances may exceed the levels specified in
this standard e.g. where a hand-held transmitter is used in proximity to an equipment. In these instances special

mitigation measures may have to be employed.
The environments encompassed by this standard are residential, commercial and light-
industrial locations, both indoor and outdoor. The following list, although not comprehensive,
gives an indication of locations which are included:
– residential properties, e.g. houses, apartments, etc.;
– retail outlets, e.g. shops, supermarkets, etc.;
– business premises, e.g. offices, banks, etc.;
– areas of public entertainment, e.g. cinemas, public bars, dance halls, etc.;
– outdoor locations, e.g. petrol stations, car parks, amusement and sports centres, etc.;
– light-industrial locations e.g. workshops, laboratories, service centres, etc.;
– car and boat.
Locations which are characterized by their mains power being supplied directly at low voltage
from the public mains are considered to be residential, commercial or light industrial.

–   – CISPR 20  IEC:2006+A1:2013

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.

CISPR 16-1-3, Specification for radio disturbance and immunity measuring apparatus and

methods - Part 1-3: Radio disturbance and immunity measuring apparatus - Ancillary

equipment - Disturbance power
IEC 60050(161), International Electrotechnical Vocabulary (IEV) – Chapter 161: Electro-

magnetic compatibility
IEC 60268-1:1985, Sound system equipment – Part 1: General
IEC 61000-4-2, Electromagnetic compatibility (EMC) – Part 4-2: Testing and measurement
techniques – Electrostatic discharge immunity test. Basic EMC Publication
IEC 61000-4-3, Electromagnetic compatibility (EMC) – Part 4-3: Testing and measurement
techniques – Radiated, radio-frequency, electromagnetic field immunity test. Basic EMC
Publication
IEC 61000-4-4, Electromagnetic compatibility (EMC) – Part 4-4: Testing and measurement
techniques – Electrical fast transient/burst immunity test. Basic EMC Publication
IEC 61000-4-6:2008, Electromagnetic compatibility (EMC) – Part 4-6: Testing and
measurement techniques – Immunity to conducted disturbances, induced by radio-frequency
fields
IEC 61672-1:2002, Electroacoustics – Sound level meters – Part 1: Specifications
ETS 300 158:1992, Satellite Earth Stations and Systems (SES) – Television Receive Only
(TVRO-FSS) Satellite Earth Stations operating in the 11/12 GHz FSS bands
ETS 300 249:1993, Satellite Earth Stations and Systems (SES) – Television Receive-Only
(TVRO) equipment used in the Broadcasting Satellite Service (BSS)
ITU-R BS.468-4, Measurement of audio-frequency noise voltage level in sound broadcasting
ITU-R BT.471-1:1986, Nomenclature and description of colour bar signals
ITU-R BT.500-10, Methodology for the subjective assessment of the quality of television
pictures
ITU-T J.61, Transmission performance of television circuits designed for use in international
connections
3 Terms, definitions and abbreviations
3.1 Terms and definitions
For the purposes of this standard, the definitions contained in IEC 60050(161) as well as the
following apply.
A non-exhaustive overview of equipment to which the standard is applicable is given in
Table 1. The terminology and abbreviations of Table 1 are also used in other tables.

CISPR 20  IEC:2006+A1:2013 – 9 –

Table 1 – Survey (non exhaustive) of receiver and associated equipment types,
including the appropriate parts of multifunction equipment

Intended for mains
powering and portable with
external power connection
Battery powered
facility
portable, without
external power
Equipment Car radio
With a Without a
connection
connection connection
facility (portable)
facility for an facility for
external an external
antenna antenna
Sound FM FM radio ant. FM radio Portable radio Car radio FM
broadcast PC FM tuner
receivers card
(radio)
LW, MW, SW (AM) AM radio ant. AM radio Car radio AM
(including
PC AM tuner
satellite
card
receivers)
Television broadcast receivers (TV) TV antenna TV Portable TV Car TV
(including satellite receivers) PC TV tuner
card
Associated Video tape/disc With tuner Ass. video Ass. video Portable ass.
equipment equipment tuner Tuner video
(ass.) (recording and/ antenna
or play-back)
Without Ass. video
tuner
Audio tape/disc equipment Ass. audio Portable ass.
audio
Other, e.g. audio amplifiers, Ass. other Portable ass.
decoders, electronic organs other, e.g. infrared
devices
3.1.1
sound receivers
appliances intended for the reception of sound broadcast and similar services for terrestrial,
cable and satellite transmissions; these sound receivers can be digital receivers with digital
incoming signals or receivers with digital processing of digital or analogue incoming signals
3.1.2
television receivers
appliances intended for the reception of television broadcast and similar services for
terrestrial, cable and satellite transmissions; these TV receivers can be digital receivers with
digital incoming signals or receivers with digital processing of digital or analogue incoming

signals
NOTE 1 Modular units which are part of sound or television receiving systems, like tuners, frequency converters,
modulators, etc. are considered to be sound or television receivers respectively.
NOTE 2 Tuners may be provided with a broadcast-satellite-receiving stage and with demodulators, decoders,
demultiplexers, D/A converters, encoders (e.g. NTSC, PAL or SECAM encoders) etc.
NOTE 3 Frequency converters may be provided with a broadcast-satellite-receiving stage and with devices which
convert the signals to other frequency bands.
NOTE 4 Receivers, tuners, or frequency converters may be tuneable or may only be able to receive a fixed
frequency.
3.1.3
associated equipment
appliance either intended to be connected directly to sound or television receivers, or to
generate or to reproduce audio or visual information; excluded are information technology
equipment even if they are intended to be connected to a television broadcast receiver
NOTE Information technology equipment is defined in CISPR 22.

–   – CISPR 20  IEC:2006+A1:2013

3.1.4
multifunction equipment
appliances in which two or more functions are provided in the same unit, for instance

television reception, radio reception, digital clock, tape-recorder or disc player etc.

3.1.5
disturbance signal
an unwanted signal which may degrade radio reception or cause malfunction in equipment;

specific unwanted signals are simulating disturbance signals, generated under laboratory

conditions
3.1.6
immunity
ability to maintain a specified performance when the equipment is subjected to disturbance
(unwanted) signals of specified levels
NOTE In this standard the specified performance is:
− a specified sound signal-to-interference ratio and/or
− no greater than just perceptible degradation of the picture when a wanted signal and an unwanted signal occur
simultaneously.
3.1.7
input immunity
immunity from unwanted signal voltages present at the antenna input terminal
3.1.8
immunity from conducted voltages
immunity from unwanted signal voltages present at the equipment terminals for audio and
mains input and audio output
3.1.9
immunity from conducted currents
immunity from unwanted signal (common mode) currents present in cables connected to the
equipment
3.1.10
immunity from radiated fields
immunity from unwanted electromagnetic fields present at the equipment
3.1.11
screening effectiveness
characteristic of a coaxial connector terminal to attenuate the transfer of internal voltages into

external fields and vice versa
3.1.12
port
particular interface of the specified apparatus with the external electromagnetic environment
(see Figure 1)
3.1.13
enclosure port
physical boundary of the apparatus through which electromagnetic fields may radiate or
impinge
CISPR 20  IEC:2006+A1:2013 – 11 –

Enclosure port
AC/DC power input port RF input/output port

Control port
Loudspeaker/ Equipment
headphone output port under test Antenna input port

Video input/output port Audio input/output port

IEC  446/02
Figure 1 – Examples of ports
3.2 Abbreviations
AC/DC Alternate Current/Direct Current
AFC Automatic Frequency Control
AM Amplitude Modulation
BSS Broadcast Satellite System
CATV Community Antenna Television
CD Compact Disc
DTH Direct To Home (satellite receiving systems)
e.m. Electromagnetic (field)
e.m.f. Electro-motive-force
ESD Electrostatic Discharge
EUT Equipment Under Test
FM Frequency Modulation
FSS Fixed Satellite System
GSM Global System for Mobile Communications
ITU-R International Telecommunication Union – Radiocommunications
LW, MW and SW Long Wave, Medium Wave and Short Wave
MATV Master Antenna Television
PC Personal Computer
RF Radio Frequency
r.m.s. Root-mean-square
TEM Transverse Electromagnetic (cell)

4 Immunity requirements
4.1 Performance criteria
4.1.1 Performance criterion A
The equipment shall continue to operate as intended during the test.
No change of actual operating state (for example change of channel) is allowed as a result of
the application of the test.
Multifunction equipment shall for each function meet the relevant requirements.
Evaluation is carried out for audio and video functions.

–   – CISPR 20  IEC:2006+A1:2013

The equipment is supposed to operate as intended if the criteria of 4.1.1.1 and/or 4.1.1.2 are

fulfilled.
4.1.1.1 Evaluation of audio quality

Unless otherwise specified in this standard, the criterion of compliance with the requirement is

a wanted to unwanted audio signal ratio of ≥40 dB at a wanted audio signal level of 50 mW, or

at another audio signal level specified by the manufacturer.

If the S/N ratio is less than 43 dB, the performance criterion for audio assessment is the

actual S/N ratio minus 3 dB.
In this case, at the beginning of the audio quality evaluation the actual S/N ratio is measured
and noted in the test report as reference value.
For AM sound receivers the criterion is ≥26 dB at 50 mW.
For AM and FM car radios and for broadcast receiver cards for computers the criterion is
≥26 dB at 500 mW.
4.1.1.2 Evaluation of picture quality
In the evaluation of picture interference the wanted test signal produces a standard picture (in
the case of video tape equipment on the screen of the test-tv-set) and the unwanted signal
produces a degradation of the picture. The degradation may be in a number of forms, such as
a superposed pattern, disturbance of synchronization, geometrical distortion, loss of picture
contrast, of colour, etc.
The criterion of compliance with the requirement is just perceptible degradation by
observation of the picture. The screen shall be observed under normal viewing conditions
(brightness 15 lx to 20 lx), at a viewing distance of six times the height of the screen.
The picture quality can also be evaluated by using objective measurement methods; one such
method is described in Annex K.
In the case of video tape equipment the test criteria relate to the picture, assessed on a test-
tv-set, which is connected to the video output terminal of the equipment.
4.1.2 Performance criterion B
The equipment shall continue to operate as intended after the test. No loss of function is
allowed after the test when the apparatus is used as intended, but failures which are

recovered automatically but which cause temporary delay in processing, are permissible. No
change of actual operating state for example change of channel or stored data and settings is
allowed as a result of the application of the test. During the test, degradation of performance
is allowed.
During the application of the test disturbance, degradation of performance is allowed.
However, no unintended change of actual operating state or stored data is allowed to persist
after the test.
After the test, the equipment shall continue to operate as intended without operator
intervention; no degradation of performance or loss of function is allowed, below a
performance level specified by the manufacturer, when the equipment is used as intended.
The performance level may be replaced by a permissible loss of performance.
If the minimum performance level (or the permissible performance loss), or recovery time, is
not specified by the manufacturer, then either of these may be derived from the product

CISPR 20  IEC:2006+A1:2013 – 13 –

description and documentation, and by what the user may reasonably expect from the

equipment if used as intended.

4.2 Applicability
Tests are applied at the relevant connectors and enclosure port of the equipment according to

4.3 through 4.7. Tests shall only be carried out where the relevant port(s) or function exist. If

more than one specific function exists, for example audio functions, then all these functions

shall be tested.
It may be determined from consideration of the electrical characteristics and usage of a

particular equipment that some of the tests are inappropriate and therefore unnecessary. In

such a case it is required that the decision not to test and the rationale leading to this
decision shall be recorded in the test report.
4.2.1 Multifunction equipment
Multifunction equipment which is subjected simultaneously to different clauses of this
standard and/or other standards shall be tested with each function operating in isolation, if
this can be achieved without modifying the equipment internally. The equipment thus tested
shall be deemed to have complied with the requirements of all clauses/standards when each
function has satisfied the requirements of the relevant clause/standard.
For equipment for which it is not practical to test with each function operating in isolation, or
where the isolation of a particular function would result in the equipment being unable to fulfil
its primary function, the equipment shall be deemed to have complied if the relevant
provisions of each clause/standard are taken into account, with the necessary functions
operative.
If the test levels for the different functions are not identical, the level for the function under
test applies, taking into account the performance criteria for this function.
Example: For a TV receiver provided with a telecommunication function, the requirements for
the telecommunication port are verified in accordance with CISPR 24.
4.2.2 PC tuner cards
For PC tuner cards immunity requirements for the antenna input connector are applicable
according to Table 2. PC tuner cards which are separately marketed for incorporation in
diverse host units shall be tested in at least one appropriate representative host unit (e.g. PC)
of the choice of the card manufacturer.

4.2.3 IR units
An IR remote control unit shall be tested together with the main unit.

–   – CISPR 20  IEC:2006+A1:2013

4.3 Immunity requirements for the antenna input connector

Measurements apply to equipment and with the performance criteria according to Table 2.

Table 2 – Antenna port
Performance
Parameter Test specification Test set-up Applicability

criteria
RF voltage See 4.3.1 See 5.3 FM radio antenna A

Differential mode Tables 3 and 4 (input immunity) PC tuner cards for FM and TV
and 4.3.2 Car radio FM
Tables 5, 5a, 5b, 5c, Satellite radio

5d and 6 TV antenna
Satellite TV
Ass. video tun. antenna
RF voltage See 4.3.3, Table 8 See 5.4 FM rad
...