SIST EN 50083-8:2003
(Main)Cable networks for television signals, sound signals and interactive services -- Part 8: Electromagnetic compatibility for networks
Cable networks for television signals, sound signals and interactive services -- Part 8: Electromagnetic compatibility for networks
Deals with cable networks for television signals, sound signals and interactive services including equipment, systems and installations - for headend-reception, processing and distribution of sound and television signals and their associated data signals and - for processing, interfacing and transmitting all kinds of signals for interactive services using all applicable transmission media.
Kabelnetze für Fernsehsignale, Tonsignale und interaktive Dienste -- Teil 8: Elektromagnetische Verträglichkeit von Kabelnetzen
Réseaux de distribution par câbles pour signaux de télévision, signaux de radiodiffusion sonore et services interactifs -- Partie 8: Compatibilité électromagnétique des réseaux
Cable networks for television signals, sound signals and interactive services - Part 8: Electromagnetic compatibility for networks
General Information
Relations
Standards Content (Sample)
SLOVENSKI STANDARD
SIST EN 50083-8:2003
01-december-2003
Cable networks for television signals, sound signals and interactive services - Part
8: Electromagnetic compatibility for networks
Cable networks for television signals, sound signals and interactive services -- Part 8:
Electromagnetic compatibility for networks
Kabelnetze für Fernsehsignale, Tonsignale und interaktive Dienste -- Teil 8:
Elektromagnetische Verträglichkeit von Kabelnetzen
Réseaux de distribution par câbles pour signaux de télévision, signaux de radiodiffusion
sonore et services interactifs -- Partie 8: Compatibilité électromagnétique des réseaux
Ta slovenski standard je istoveten z: EN 50083-8:2002
ICS:
33.060.40 Kabelski razdelilni sistemi Cabled distribution systems
33.100.01 Elektromagnetna združljivost Electromagnetic compatibility
na splošno in general
SIST EN 50083-8:2003 en
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
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SIST EN 50083-8:2003
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SIST EN 50083-8:2003
EUROPEAN STANDARD EN 50083-8
NORME EUROPÉENNE
EUROPÄISCHE NORM May 2002
ICS 29.020; 33.060.40 Supersedes EN 50083-8:2000
English version
Cable networks for television signals, sound signals
and interactive services
Part 8: Electromagnetic compatibility for networks
Réseaux de distribution par câbles Kabelnetze für Fernsehsignale,
pour signaux de télévision, signaux de Tonsignale und interaktive Dienste
radiodiffusion sonore et services Teil 8: Elektromagnetische Verträglichkeit
interactifs von Kabelnetzen
Partie 8: Compatibilité électromagnétique
des réseaux
This European Standard was approved by CENELEC on 2001-12-01. CENELEC members are bound to
comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on
application to the Central Secretariat or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CENELEC member into its own language and
notified to the Central Secretariat has the same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Czech Republic,
Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands,
Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.
CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
Central Secretariat: rue de Stassart 35, B - 1050 Brussels
© 2002 CENELEC -All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 50083-8:2002 E
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Foreword
This European Standard was prepared by CENELEC Technical Committee TC 209, "Cable networks for
television signals, sound signals and interactive services" on the basis of EN 50083-8:2000 and the first
amendment to EN 50083-8.
The text of this first amendment was submitted to the Unique Acceptance Procedure and was approved
by CENELEC on 2001-12-01 to be published as part of a second edition of EN 50083-8.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement (dop) 2002-12-01
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2004-12-01
__________
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Content
Page
1 Scope . 4
1.1 General. 4
1.2 Specific scope of this part 8. 4
2 Normative references. 5
3 Terms, definitions, symbols and abbreviations. 6
3.1 Terms and definitions. 6
3.2 Symbols. 8
3.3 Abbreviations . 8
4 Methods of measurement. 9
4.1 Radiation from cable networks. 9
4.2 Immunity of cable networks . 13
5 Performance requirements . 14
5.1 Radiation from cable networks. 14
5.2 Immunity of cable networks . 15
Annexes
Annex A (informative) A-deviations. 17
Annex B (informative) Frequency ranges of typical safety of life services. 26
Annex C (informative) Interdependence between the maximum allowable field
strength and the minimum carrier-to-interference ratio . 27
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1 Scope
1.1 General
Standards of EN 50083 series deal with cable networks for television signals, sound signals and
interactive services including equipment, systems and installations
� for headend-reception, processing and distribution of sound and television signals and their
associated data signals and
� for processing, interfacing and transmitting all kinds of signals for interactive services
using all applicable transmission media.
All kinds of networks like
� CATV-networks
� MATV- and SMATV-networks
� individual receiving networks
and all kinds of equipment, systems and installations installed in such networks, are within this scope
The extent of this standardisation work is from the antennas, special signal source inputs to the headend
or other interface points to the network up to the system outlet or the terminal input, where no system
outlet exists.
The standardisation of any user terminals (i.e. tuners, receivers, decoders, multimedia terminals etc.) as
well as of any coaxial and optical cables and accessories therefor is excluded.
1.2 Specific scope of this part 8
This standard applies to the radiation characteristics and immunity to electromagnetic disturbance of
cable networks for television signals, sound signals and interactive services and covers the frequency
range 0,15 MHz to 3,0 GHz.
This standard specifies EMC performance requirements and lays down the methods of measurement.
Cable networks beyond the system outlets (e.g. the receiver lead, in simplest terms) which begin at the
system outlet and end at the subscriber's terminal equipment shall comply with these recommendations
provided that no other specific provisions apply.
Requirements for the electromagnetic compatibility of receiver leads are laid down in EN 60966�2�4,
EN 60966�2�5 and EN 60966�2�6.
To minimise the risk of interference to other radio services caused by possible radiation from a cable
network and to limit the possible penetration of external signals which may interfere with the operation of
a network, it is necessary not only to use equipment which satisfies the requirements of EN 50083-2
regarding limits of radiation and of immunity to external fields but also to ensure the integrity of all cable
connections on each item of active or passive cable network equipment.
Cable networks employing coaxial cables can be a source of interference to a wide range of services that
utilise the radio frequency spectrum. These include not only the emergency services, safety of life,
broadcasting, aeronautical and radio navigation services but also land mobile, amateur and cellular radio
services.
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As existing and planned radio services need to be protected, radiation limits specified for cable networks
should complied with.
Additional protection for certain services may be required by national regulations.
2 Normative references
This European Standard incorporates, by dated or undated reference, provisions from other publications.
These normative references are cited at the appropriate places in the text and the publications are listed
hereafter. For dated references, subsequent amendments to or revisions of any of these publications
apply to this European Standard only when incorporated in it by amendment or revision. For undated
references the latest edition of the publication referred to applies (including amendments).
EN 50083 Cable networks for television signals, sound signals and interactive
services
EN 50083-2 2001 Part 2: Electromagnetic compatibility for equipment
EN 50083-3 2002 Part 3: Active wideband equipment for coaxial cable networks
EN 50083-4 1998 Part 4: Passive wideband equipment for coaxial cable networks
EN 50083-5 2000 Part 5: Headend equipment (to be published)
EN 50083-6 1997 Part 6: Optical equipment
EN 50083-7 1996 Part 7: System performance
+ A1 2000
EN 50117 Series Coaxial cables used in cable networks
EN 60966�2�4 1997 Radio frequency and coaxial cable assemblies - Part 2�4: Detail
specification for cable assemblies for radio and TV receivers -
Frequency range 0 to 3 000 MHz, IEC 60169�2 connectors
EN 60966�2�5 1998 Radio frequency and coaxial cable assemblies - Part 2�5: Detail
specification for cable assemblies for radio and TV receivers -
Frequency range 0 to 1 000 MHz, IEC 60169�2 connectors
EN 60966�2�6 1998 Radio frequency and coaxial cable assemblies - Part 2�6: : Detail
specification for cable assemblies for radio and TV receivers -
Frequency range 0 to 3 000 MHz, IEC 60169�24 connectors
IEC 60050(161) International Electrotechnical Vocabulary
Chapter 161: Electromagnetic compatibility.
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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3 Terms, definitions, symbols and abbreviations
3.1 Terms and definitions
For the purposes of this standard, the definitions contained in IEC 60050(161) "Electromagnetic
compatibility" apply. The most important definitions of IEC 60050(161) are repeated hereafter with the
IEV-numbering given in brackets. In addition some more specific definitions, used in this standard, are
listed.
3.1.1
(electromagnetic) radiation [IEV 161-01-10]
1. phenomenon by which energy in the form of electromagnetic waves emanates from a source into
space
2. energy transferred through space in the form of electromagnetic waves
NOTE By extension, the term "electromagnetic radiation" sometimes also covers induction phenomena.
3.1.2
immunity (to a disturbance) [IEV 161-01-20]
ability of a device, equipment or system to perform without degradation in the presence of an
electromagnetic disturbance
3.1.3
electromagnetic disturbance [IEV 161-01-05]
any electromagnetic phenomenon which may degrade the performance of a device, equipment or
system, or adversely affect living or inert matter
NOTE An electromagnetic disturbance may be an electromagnetic noise, an unwanted signal or a change in the
propagation medium itself.
3.1.4
screening effectiveness
ability of an equipment or system to attenuate the influence of electromagnetic fields from outside the
equipment or system or to suppress the radiation of electromagnetic fields from inside the equipment or
system
3.1.5
well-screened
A test set-up can be considered "well-screened" if its radiation level, when terminated with a matched
load, is at least 20 dB below the expected radiation level of the equipment under test, the test set-up and
the equipment being supplied with the same input signal level.
3.1.6
electromagnetic interference EMI (abbreviation) [IEV 161-01-06]
degradation of the performance of an equipment, transmission channel or system caused by an
electromagnetic disturbance
3.1.7
operating frequency range
passband for the wanted signals for which the equipment has been designed
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3.1.8
carrier-to-interference ratio
minimum level difference measured at the output of an active equipment or at any other interface within
the network between the wanted signal and
� intermodulation products of the wanted signal and/or unwanted signals generated due to non-
linearities;
� harmonics generated by an unwanted signal;
� unwanted signals that have penetrated into the operating frequency range;
� unwanted signals that have been converted to the frequency range to be protected (operating
frequency range)
3.1.9
headend
equipment which is connected between receiving antennas or other signal sources and the remainder of
the cable network, to process the signals to be distributed
NOTE The headend may, for example, comprise antenna amplifiers, frequency converters, combiners, separators
and generators.
3.1.10
system outlet
device for interconnecting a subscriber feeder and a receiver lead
3.1.11
spur network
cable network normally laid out inside buildings to which splitters, subscriber taps or looped system
outlets are connected
3.1.12
ignition noise
unwanted emission of electromagnetic energy, predominantly impulsive in content, arising from the
ignition system within a vehicle or device
3.1.13
building penetration loss
ability of buildings, in which networks for distribution of television and sound are located, to attenuate the
influence of electromagnetic fields from outside the buildings or to suppress the radiation of
electromagnetic fields from inside the buildings
3.1.14
disturbance level
level of an electromagnetic disturbance at a given location, which results from all contributing
(interference) sources
3.1.15
degradation (of performance) [IEV 161-01-19]
undesired departure in the operational performance of any device, equipment or system from its intended
performance
NOTE The term "degradation" can apply to temporary or permanent failure.
3.1.16
subscriber's feeder
feeder connecting a subscriber tap to a system outlet or, where the latter is not used, directly to the
subscriber equipment
NOTE A subscriber feeder may include filters and balun transformer.
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3.1.17
receiver lead
lead which connect the system outlet to the subscriber equipment
3.1.18
external immunity [IEV 161-03-07]
ability of a device, equipment or network to perform without degradation in the presence of
electromagnetic disturbances entering other than via its normal input terminals or antenna.
3.2 Symbols
3.2.1 Symbols used in equations
A cable loss between antenna and spectrum analyser
C
A attenuator loss
T
E field strength limit for the considered frequency
L
G gain of the low-noise amplifier
G gain of the transmitting antenna related to a half-wave dipole
A
k antenna factor
A
P radiated power of the network related to a half-wave dipole
P available output power of the signal generator
SG
U level corresponding to the permitted limit
L
3.2.2 Symbols used in figures
tuneable bandpass filter
pre-amplifier
3.3 Abbreviations
AM Amplitude Modulation
CATV Community Antenna Television (network)
DSC Distress, Safety and Calling
EMC Electromagnetic Compatibility
EMI Electromagnetic Interference
EPIRB Emergency Position Indicating Radiobeacons
FM Frequency Modulation
ILS Instrument Landing System
ITU-R International Telecommunication Union - Radiocommunication
MATV Master Antenna Television (network)
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RF Radio Frequency
SMATV Satellite Master Antenna Television (network)
TV Television
VOR VHF Omnidirectional Range
VSB Vestigial Side Band
NOTE Only the abbreviations used in the English version of this part of EN 50083 are mentioned in this subclause.
The German and the French versions of this part may use other abbreviations. Refer to 3.3 of each language
versions for details.
4 Methods of measurement
These methods of measurement describe the procedures for the testing of cable networks. The purpose
of the measurements is to determine:
� the level of radiation generated by cable networks and
� the immunity of cable networks to external field strengths (e.g. those radiated by other
radiocommunication services and RF applications).
The measurements cover the essential parameters and environmental conditions in order to assess:
� cases of electromagnetic incompatibility between cable networks and other electrical or electronic
equipment, networks, installations or other cabled networks with respect to the intended operation of
such cable networks.
During the test the cable network shall operate with normal signal levels at the subscriber outlets. If the
stream is interactive, typical levels of the return path signals shall be maintained during the test.
N OTE Methods of measurement for digitally modulated signals are under consideration.
4.1 Radiation from cable networks
The methods described hereafter are applicable to the measurement of radiation from cable networks
(combination of cables, equipment and networks).
Testing of the cable networks for compliance with the relevant limits may be initially carried out with the
terminal equipment connected. Where limits are exceeded, individual sections of the network (e.g.
headend, satellite receiving outdoor unit, cable network, distribution installation beyond the system outlets
and terminal equipment) may be tested in succession to determine beyond any doubt which section of the
network does not comply with the limits.
The number of test frequencies shall be selected to give a realistic representation of the radiation pattern
throughout the operating frequency range and to enable the maximum level of radiation to be recorded
and the results interpreted accurately.
The field strength measurement procedure is used in order to achieve results which are sufficiently
accurate and do not require excessive technical effort.
The substitution measurement technique is applied to carry out more accurate measurements of the
radiated disturbance power level generated by any part of the network.
If discussions arise about the actual radiation from a cable network, the substitution method according to
4.1.2 has to be applied.
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The maximum permitted radiation level is given in 5.1, Table 1.
The following problems can cause radiation from cable networks:
� poor or faulty screening of passive equipment (plugs, splitters, etc.);
� poor or faulty screening of active equipment (amplifiers, converters, etc.);
� poor or faulty screening of the distribution cables against induced voltages;
� excessive impedance in the ground connections of the input terminals of active and passive
equipment;
� insufficient rejection of power supply borne interference on mains powered equiment;
� inadequate mounting of connectors on cables;
� damage of the screening of cables or connectors.
4.1.1 Field strength method
The field strength method uses a suitable magnetic loop antenna in the frequency range from 5 MHz to
30 MHz and a suitable electromagnetic field antenna in the frequency range 30 MHz to 950 MHz.
Usually a loop antenna is conventionally calibrated in terms of "equivalent electric component" of the
electromagnetic field. If a loop antenna calibrated in terms of magnetic field is used, the level of the
equivalent electric field is deduced from the level of the measured magnetic field according to the
following formula:
E = H + 51,5
where
E is the equivalent electric field level in dB(�V/m)
H is the measured magnetic field level in dB(�A/m)
51,5 = 20 lg(120�) is the free space impedance in dB(�).
4.1.1.1 Equipment required
The equipment required for the measurement of the radiation from a network is listed below:
� a suitable spectrum analyser (battery powered) with a digital recorder or a plotter;
The spectrum analyser should cover the frequencies distributed within the network with a resolution
bandwidth (IF bandwidth) according to CISPR 16 (see Table 1) and an appropriate slow sweep
speed.
� a calibrated loop antenna according to CISPR 16 in the frequency range 5 MHz to 30 MHz;
� calibrated electromagnetic field antennas in the frequency range 30 MHz to 950 MHz;
NOTE It is strongly recommended that an antenna with very broad bandwidth is used to reduce the expense of
the measurements. It is also recommended that a directive antenna is used to be able to test each side of the
street independently of the other one.
A good choice would be, for example, a log-periodic antenna covering the frequency range from 80 MHz to
950 MHz.
� a calibrated low-noise amplifier covering the required frequency range;
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� an antenna cable of known loss/frequency characteristic;
� a suitable vehicle to carry the above equipment with the broadband antenna fixed on the top of the
vehicle and oriented in order to get the maximum reception level perpendicular to the driving
direction.
4.1.1.2 Measurement procedure
The antenna shall be connected to the input of the spectrum analyser via the low-noise amplifier, if
necessary, with a well-screened and well-matched coaxial cable.
Before starting measurements, a calibration procedure (see 4.1.1.3) is required to obtain the limit line
related to the limit field values (see 5.1). Then, the measurement procedure can start for the first street,
following the centre line of the lane closest to the building, where the cable network is installed.
It is important to drive the vehicle slowly along the street, according to the spectrum analyser operation, to
get a clear overview on the screen of the spectrum analyser.
A survey is first conducted in order to ascertain the frequencies and field strengths of local transmitters so
that these may be eliminated from the measurement results.
If one or more carriers exceed the limit line, the vehicle stops and the operator checks the frequency(ies)
of this (or those) carrier(s).
To verify, from which part of the network the measured radiation is coming out, the system signal in the
measured frequency range may be temporarily switched off in the area of interest.
If one or more of the exceeding carriers are emanating from the network, then the operator shall record
the spectrum analyser pattern and note that place on the map of the town for a future repair. After
repair, the field strength should be measured again.
Because of the antenna directivity, the vehicle has to be driven over each street twice to test both sides.
4.1.1.3 Calibration procedure
When a calibrated broadband antenna is used, the limit line shall be obtained for each frequency by
calculation with the formula and using the antenna factor given by the antenna manufacturer:
U = E � (k + A )
L L A C
where:
U is the level corresponding to the permitted limit, in dB(µV);
L
E is the field strength limit for the considered frequency, in dB(µV/m);
L
k is the antenna factor, in dB;
A
A is the cable loss between antenna and spectrum analyser, in dB.
C
If the field strength limit is a very low value, a low noise preamplifier shall be inserted between the
antenna and the spectrum analyser.
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In that case, the formula shall be:
U = E � (k + A ) + G
L L A C
where G is the gain of the low-noise amplifier, in dB.
4.1.2 Power method (Substitution measurement method)
In order to obtain more accurate results of the equivalent radiated disturbance power generated by a
network or if the measurement accuracy achieved on the basis of previous measurement procedures is
not sufficient, the substitution measurement method shall be applied.
In the frequency range of 5 MHz to 30 MHz the substitution measurement method is not practical.
4.1.2.1 Equipment required
The equipment required for the measurement of the radiation from a network is listed below:
� a selective measuring receiver covering the frequency range of interest and sufficient sensitivity;
� broadband antennas for the frequency range from 30 MHz to 950 MHz and a log-periodic antenna
for the frequency range from 950 MHz to 3000 MHz;
� a signal generator covering the frequency range of interest and sufficient output power;
� a transmitting antenna with a front-to-back ratio of minimum 10 dB and a known gain;
� an attenuator to be connected to the terminals of the transmitting antenna;
� suitable measurement cables;
� suitable mounting equipment to enable the height and polarisation of the transmitting antenna to be
adjusted (e.g., a telescopic mast).
4.1.2.2 Measurement procedure
First the maximum radiation of the network in the direction of interest shall be measured at a suitable
distance with a broadband receiving antenna and a measuring receiver (spectrum analyser) changing the
height and polarisation of the antenna to obtain a maximum reading.
The maximum measured values and their related frequencies shall be noted (level a ).
1
Then the cable network (either the complete network or a section of it) is replaced by a transmitting
antenna supplied by a calibrated signal generator. The antenna shall be a type with a front-to-back ratio
of minimum 10 dB, to minimise the reflection effects from the building.
An attenuator connected to the base of the antenna is required in all cases in order to avoid any
mismatch. The transmitting antenna shall be set up in front of the wall of the building in the area of the
supposed maximum radiation source.
To minimise other unwanted reflections, the signal generator shall at first be set to a level P , so that a
SG2
sufficient readable value can be noted on the measuring receiver (level a ). The level P shall be
2 SG2
fixed.
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Then the position (height and polarisation) of the transmitting antenna shall be varied in order to get the
maximum reading on the measurement receiver (equal or greater than the level a ). In this position the
2
transmitting antenna shall be fixed. Now the RF level of the signal generator (P ) shall be varied to
SG1
obtain the same level a on the measuring receiver.
1
The resulting disturbance power shall be calculated by following formula:
P = P � A � A + G
SG1 C T A
where:
P is the radiated power of the network related to a half-wave dipole, in dB(pW);
P is the available output power of the signal generator, in dB(pW);
SG1
A is the cable attenuation, in dB;
C
A is the attenuator loss, in dB;
T
G is the gain of the transmitting antenna related to a half-wave dipole in dB.
A
The maximum disturbance power shall meet the requirements given in 5.1.
By the above mentioned measurement method, the ground reflections are eliminated with sufficient
accuracy.
4.2 Immunity of cable networks
Interference can enter cable networks by the following means:
� poor or faulty screening of passive equipment (plugs, splitters, etc);
� poor or faulty screening of active equipment (amplifiers, converters, etc);
� poor or faulty screening of the distribution cables against induced voltages;
� poor or faulty screening of the distribution cables against induced currents;
� excessive impedance in the ground connections of the input terminals of active and passive
equipment;
� insufficient rejection of power supply borne interference on mains powered equipment.
� inadequate mounting of connectors on cables;
� damage of the screening of cables or connectors.
The carrier-to-interference ratio caused by an external field at any system outlet shall be measured by
means of a suitable measuring receiver or spectrum analyser. The results shall comply with the limits
given in 5.2.
4.2.1 Measurement procedure using a disturbing high-power local transmitter
In the case of disturbance, the carrier-to-interference ratio shall be measured at the outlets subject to
disturbance.
At first, the wanted signal level in the disturbed channel shall be measured. After that, the cable network
shall be disconnected from the interchange point or the antennas. The disconnected inputs shall be
terminated with 75 � terminating loads.
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