SIST EN 62153-4-7:2007
(Main)Metallic communication cables test methods -- Part 4-7: Electromagnetic compatibility (EMC) - Test method for measuring the transfer impedance and the screening - or the coupling attenuation - Tube in tube method
Metallic communication cables test methods -- Part 4-7: Electromagnetic compatibility (EMC) - Test method for measuring the transfer impedance and the screening - or the coupling attenuation - Tube in tube method
This triaxial method is suitable to determine the surface transfer impedance and/or screening attenuation and coupling attenuation of mated screened connectors (including the connection between cable and connector) and cable assemblies. This method could also be extended to determine the transfer impedance, coupling or screening attenuation of balanced or multipin connectors and cable assemblies.
Prüfverfahren für metallische Kommunikationskabel -- Teil 4-7: Elektromagnetische Verträglichkeit (EMV) - Messverfahren zur Messung der Kopplungswiderstandes und der Schirmdämpfung oder der Kopplungsdämpfung - Rohr-im-Rohr-Verfahren
Méthodes d'essai des câbles métalliques de communication -- Partie 4-7: Compatibilité électromagnétique (CEM) - Méthode d'essai pour mesurer l'impédance de transfert et l'affaiblissement d'écran - ou l'affaiblissement de couplage - Méthode des tubes concentriques
convient pour déterminer l'impédance surfacique de transfert et/ou l'affaiblissement d'écran et l'affaiblissement de couplage de connecteurs blindés adaptés (y compris la connexion entre un câble et un connecteur) et d'ensembles de câbles. Cette méthode peut également être étendue pour déterminer l'impédance de transfert, l'affaiblissement d'écran ou de couplage de connecteurs symétriques ou à plusieurs broches et d'ensembles de câbles.
Preskušalne metode za kovinske komunikacijske kable – 4-7. del: Elektromagnetna združljivost (EMC) – Preskušalna metoda za meritve prehodne impedance in zaslanjanja – ali sklopnega slabljenja– Metoda cev v cevi (IEC 62153-4-7:2006)
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Standards Content (Sample)
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.Metallic communication cables test methods -- Part 4-7: Electromagnetic compatibility (EMC) - Test method for measuring the transfer impedance and the screening - or
the coupling attenuation - Tube in tube method (IEC 62153-4-7:2006)Preskušalne metode za kovinske komunikacijske kable – 4-7. del: Elektromagnetna združljivost (EMC) – Preskušalna metoda za meritve prehodne impedance in zaslanjanja – ali sklopnega slabljenja– Metoda cev v cevi (IEC 62153-4-7:2006)Méthodes d'essai des câbles métalliques de communication -- Partie 4-7: Compatibilité électromagnétique (CEM) - Méthode d'essai pour mesurer l'impédance de transfert et l'affaiblissement d'écran - ou l'affaiblissement de couplage - Méthode des tubes concentriques (IEC 62153-4-7:2006)Prüfverfahren für metallische Kommunikationskabel -- Teil 4-7: Elektromagnetische Verträglichkeit (EMV) - Messverfahren zur Messung der Kopplungswiderstandes und der Schirmdämpfung oder der Kopplungsdämpfung - Rohr-im-Rohr-Verfahren (IEC 62153-4-7:2006)Ta slovenski standard je istoveten z:EN 62153-4-7:2006SIST EN 62153-4-7:2007en,fr,de33.120.10Koaksialni kabli. ValovodiCoaxial cables. Waveguides33.100.01Elektromagnetna združljivost na splošnoElectromagnetic compatibility in generalICS:SLOVENSKI
STANDARDSIST EN 62153-4-7:200701-november-2007
EUROPEAN STANDARD EN 62153-4-7 NORME EUROPÉENNE
EUROPÄISCHE NORM August 2006
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
© 2006 CENELEC -
All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 62153-4-7:2006 E
ICS 33.120.10; 33.100
English version
Metallic communication cables test methods
Part 4-7: Electromagnetic compatibility (EMC) -
Test method for measuring the transfer impedance and
the screening - or the coupling attenuation -
Tube in tube method (IEC 62153-4-7:2006)
Méthodes d'essai des câbles
métalliques de communication
Partie 4-7: Compatibilité électromagnétique (CEM) -
Méthode d'essai pour mesurer l'impédance de transfert et l'affaiblissement d'écran -
ou l'affaiblissement de couplage - Méthode des tubes concentriques
(CEI 62153-4-7:2006)
Prüfverfahren für metallische Kommunikationskabel
Teil 4-7: Elektromagnetische Verträglichkeit (EMV) -
Messverfahren zur Messung
der Kopplungswiderstandes und
der Schirmung -
oder der Kopplungsdämpfung -
Rohr-im-Rohr-Verfahren (IEC 62153-4-7:2006)
This European Standard was approved by CENELEC on 2006-08-01. 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, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom.
EN 62153-4-7:2006
- 2 - Foreword The text of the International Standard IEC 62153-4-7:2006, prepared by SC 46A, Coaxial cables, of IEC TC 46, Cables, wires, waveguides, R.F. connectors, R.F. and microwave passive components and accessories, was submitted to the formal vote and was approved by CENELEC as EN 62153-4-7 on 2006-08-01 without any modification. 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)
2007-08-01 – latest date by which the national standards conflicting
with the EN have to be withdrawn
(dow)
2009-08-01 Annex ZA has been added by CENELEC. __________ Endorsement notice The text of the International Standard IEC 62153-4-7:2006 was approved by CENELEC as a European Standard without any modification. __________
- 3 -
Annex ZA
(normative)
Normative references to international publications with their corresponding European publications
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.
NOTE
When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD applies.
Publication Year Title EN/HD Year
IEC 61196-1 2005 Coaxial communication cables
Part 1: Generic specification - General, definitions and requirements - -
IEC 62153-4-4 2006 Metallic communication cable test methods
Part 4-4: Electromagnetic compatibility
(EMC) - Shielded screening attenuation,
test method for measuring of the screening attenuation as up to and above 3 GHz - -
- - Communication cables - Specifications for test methods
Part 1-6: Electrical test methods - Electromagnetic performance EN 50289-1-6 2002
NORME INTERNATIONALECEIIECINTERNATIONALSTANDARD 62153-4-7Première éditionFirst edition2006-04Méthodes d'essai des câbles métalliques de communication – Partie 4-7: Compatibilité électromagnétique (CEM) –
Méthode d'essai pour mesurer l'impédance
de transfert et l'affaiblissement d'écran – ou l'affaiblissement de couplage –
Méthode des tubes concentriques Metallic communication cables test methods – Part 4-7: Electromagnetic compatibility (EMC) – Test method
for measuring the transfer impedance and the screening – or the coupling attenuation – Tube in tube method Pour prix, voir catalogue en vigueur For price, see current catalogue© IEC 2006
Droits de reproduction réservés
⎯
Copyright - all rights reservedAucune partie de cette publication ne peut être reproduite ni utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique, y compris la photocopie et les microfilms, sans l'accord écrit de l'éditeur. No part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from the publisher. International Electrotechnical Commission,
3, rue de Varembé, PO Box 131, CH-1211 Geneva 20, SwitzerlandTelephone: +41 22 919 02 11 Telefax: +41 22 919 03 00 E-mail: inmail@iec.ch
Web: www.iec.ch CODE PRIX PRICE CODE VCommission Electrotechnique InternationaleInternational Electrotechnical Commission
62153-4-7 © IEC:2006 – 3 –
CONTENTS FOREWORD.7INTRODUCTION.111Scope.132Normative references.133Terms and definitions.134Principle of the test method.175Theoretical background.216Procedure.216.1Equipment.216.2Connection between extension tube device under test.216.3Dynamic range respectively noise floor.236.4Impedance of the inner system.236.5Sample preparation.297Measurement.317.1Transfer impedance.317.2Screening attenuation.337.3Coupling attenuation.338Expression of results.358.1Transfer impedance and effective transfer impedance.358.2Screening attenuation.358.3Coupling attenuation.378.4Requirement.39 Annex A (informative) Measurements of the screening effectiveness of connectors and cable assemblies.41Annex B (informative) Influence of contact resistances.63Bibliography.67Figure 1 – Definition of ZT.15Figure 2 – Principle of the test set-up to measure transfer impedances and screening or coupling attenuation of connectors.19Figure 3 – Principle of the test set-up to measure transfer impedances and screening attenuation of short cable assemblies.19Figure 4 – Principle set-up for verification test.23Figure 5 – Impedance matching for Z1 <50 Ω.27Figure 6 – Impedance matching for Z1 >50 Ω.27Figure 7a – Principle preparation of balanced or multiconductor connectors for transfer impedance and screening attenuation.29Figure 7b – Principle preparation of balanced or multiconductor connectors for coupling attenuation.31Figure 7 – Preparation of balanced or multiconductor connectors.31
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Figure 8 – Measuring the transfer impedance with tube in tube.31Figure 9 – Measuring the screening attenuation with tube in tube.33Figure 10 – Measuring the coupling attenuation with tube in tube.35Figure 11 – Typical measurement of a connector of 0,04 m length with 1 m extension tube.39Figure A.1 – Equivalent circuit of coupled transmission lines.43Figure A.2 – Summing function S.45Figure A.3 – Calculated coupling transfer function (l = 1 m; er1 = 2,3; er2 = 1; ZF= 0).47Figure A.4 – Triaxial set-up for the measurement of the screening attenuation aS and the transfer impedance ZT.51Figure A.5 – Simulation of a cable assembly (logarithmic scale).53Figure A.6 – Simulation of a cable assembly (linear scale).53Figure A.7 – Triaxial set-up with extension tube for short cable assemblies.55Figure A.8 – Triaxial set-up with extension tube for connectors.57Figure A.9 – Simulation, logarithmic frequency scale.59Figure A.10 – Measurement, logarithmic frequency scale.59Figure A.11 – Simulation, linear frequency scale.59Figure A.12 – Measurement, linear frequency scale.59Figure A.13 – Simulation, logarithmic frequency scale.59Figure A.14 – simulation, linear frequency scale.59Figure B.1 – Contact resistances of the test set-up.63Figure B.2 – Equivalent circuit of the test set-up.65
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INTERNATIONAL ELECTROTECHNICAL COMMISSION____________ METALLIC COMMUNICATION CABLE TEST METHODS – Part 4-7: Electromagnetic compatibility (EMC) –
Test method for measuring the transfer impedance
and the screening – or the coupling attenuation – Tube in tube method FOREWORD 1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising all national electrotechnical committees (IEC National Committees). The object of 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, IEC publishes International Standards, Technical Specifications, Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). 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. 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 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 IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any misinterpretation by any end user. 4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications transparently to the maximum extent possible in their national and regional publications. Any divergence between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter. 5) IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any equipment declared to be in conformity with an IEC Publication. 6) All users should ensure that they have the latest edition of this publication. 7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and members of its technical committees and IEC National Committees for any personal injury, property damage or other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) andexpenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is indispensable for the correct application of this publication. 9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent rights. IEC shall not be held responsible for identifying any or all such patent rights. International Standard IEC 62153-4-7 has been prepared by subcommittee 46A: Coaxial cables, of IEC technical committee 46: Cables, wires, waveguides, r.f. connectors, r.f. and microwave passive components and accessories. The text of this standard is based on the following documents: FDIS Report on voting 46A/797/FDIS 46A/414/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.
62153-4-7 © IEC:2006 – 9 –
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2. IEC 62153 consists of the following parts, under the general title Metallic communication cable test methods:Part 1-1:
Electrical í Measurement of the pulse/step return loss in the frequency domain using the Inverse Discrete Fourier Transformation (IDFT) Part 1-2:
Reflection measurement correction 1Part 4-0:
Electromagnetic Compatibility (EMC) í Relationship between Surface transfer impedance and Screening attenuation, recommended limits 1Part 4-1:
Electromagnetic Compatibility (EMC) í Introduction to electromagnetic (EMC) screening measurements 1Part 4-2:
Electromagnetic compatibility (EMC) í Screening and coupling attenuation íInjection clamp method Part 4-3:
Electromagnetic Compatibility (EMC) í Surface transfer impedance í Triaxial method
Part 4-4:
Electromagnetic Compatibility (EMC) í Shielded screening attenuation, test method for measuring of the screening attenuation "as " up to and above 3 GHz
Part 4-5:
Electromagnetic Compatibility (EMC) í Coupling or screening attenuation íabsorbing clamp method
Part 4-6:
Electromagnetic Compatibility (EMC) í Surface transfer impedance í line injection method
Part 4-7:
Electromagnetic Compatibility (EMC) í Part 4-7: Electromagnetic compatibility (EMC) – Test method for measuring the transfer impedance and the screening – or the coupling attenuation –Tube in tube method Part 4-8:
Electromagnetic Compatibility (EMC) í Capacitive Coupling Admittance 1The committee has decided that the contents of this publication will remain unchanged until the maintenance result 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. ————————— 1 Under consideration.
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INTRODUCTION The shielded screening attenuation test set-up according to IEC 62153-4-4 (triaxial method) has been extended to take into account the particularities of electrical short elements like connectors and cable assemblies. Due to the concentric outer tube of the triaxial set-up, measurements are independent of irregularities on the circumference and outer electromagnetic fields. With the use of an additional resonator tube (inner tube respectively tube in tube) a system is created where the screening effectiveness of an electrically short device is measured in realistic and controlled conditions. Also a lower cut off frequency for the transition between electrically short (transfer impedance ZT)and electrically long (screening attenuation as) can be achieved. A wide dynamic and frequency range can be applied to test even super screened connectors and assemblies with normal instrumentation from low frequencies up to the limit of defined transversal waves in the outer circuit at approximately 4 GHz.
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METALLIC COMMUNICATION CABLE TEST METHODS – Part 4-7: Electromagnetic compatibility (EMC) –
Test method for measuring the transfer impedance
and the screening – or the coupling attenuation – Tube in tube method 1 Scope This triaxial method is suitable to determine the surface transfer impedance and/or screening attenuation and coupling attenuation of mated screened connectors (including the connection between cable and connector) and cable assemblies. This method could also be extended to determine the transfer impedance, coupling or screening attenuation of balanced or multipin connectors and cable assemblies. 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. IEC 61196-1:2005, Coaxial communication cables – Part 1: Generic specification – General, definitions and requirements IEC 62153-4-4, Metallic communication cable test methods – Part 4-4: Electromagnetic compatibility (EMC) – Shielded screening attenuation, test method for measuring of the screening attenuation as up to and above 3 GHz23 Terms and definitions For the purposes of this document, the following terms and definitions apply. 3.1
surface transfer impedance ZTfor an electrically short screen, quotient of the longitudinal voltage U1 induced to the inner circuit by the current I2 fed into the outer circuit or vice versa [Ω] (see Figure 1) The value ZT of an electrically short screen is expressed in ohms [Ω] or decibels in relation to 1Ω.————————— 2To be published
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U1l < λ/10 I2I2IEC
598/06 Figure 1 – Definition of ZT21TIUZ=(1) ¸¸¹·¨¨©§Ω×+=Ω1log20)(dBT10TZZ(2) 3.2
effective transfer impedance ZTEimpedance defined as: TFTEmaxZZZ±=(3) where ZFis the capacitive coupling impedance. 3.3
screening attenuation asfor electrically long devices, i.e. above the cut-off frequency, logarithmic ratio of the feeding power P1 and the periodic maximum values of the coupled power Pr,max in the outer circuit ¸¸¹·¨¨©§×−=1maxr,10sEnvlog10PPa(4) The screening attenuation of an electrically short device is defined as: TE10s150log20ZaΩ×⋅−=(5) where 150 Ωis the standardized impedance of the outer circuit.
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3.4
coupling attenuation aCfor a screened balanced device, sum of the unbalance attenuation aU of the symmetric pair and the screening attenuation aS of the screen of the device under test For electrically long devices, i.e. above the cut-off frequency, the coupling attenuation aC is defined as the logarithmic ratio of the feeding power P1 and the periodic maximum values of the coupled power Pr,max in the outer circuit. 3.5
coupling length the coupling length is electrically short, if r1o10ελ×>l or r1o10ε××lcf(7) where l is the effective coupling length in m; λo is the free space wave length in m; r1ε is the resulting relative permittivity of the dielectric of the cable; r2ε is the resulting relative permittivity of the dielectric of the secondary circuit; f is frequency in Hz; cois the velocity of light in free space. 3.6
device under test device consisting of the mated connectors with their attached cables 4 Principle of the test method Usually RF connectors have mechanical dimensions in the longitudinal axis in the range of 20 mm to maximum 50 mm. With the definition of electrical short elements we get cut off or corner frequencies or corner for the transition between electrically short and long elements of about 1 GHz or higher for usual RF-connectors. In the frequency range up to the cut off frequency, where the device under test (DUT) is electrically short, the transfer impedance of the DUT can be measured. For frequencies above the cut-off frequency, where the DUT is electrically long, the screening attenuation can be measured.
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By extending the electrically length of the RF-connector by a RF-tightly closed metallic extension tube (tube in tube), the tested combination becomes electrically long and the cut-off frequency is moved towards the lower frequency range. In this way, also in the lower frequency range, the screening attenuation may be measured and the effective transfer impedance of electrical short devices calculated. The test set up is a triaxial system consisting of the DUT, a solid metallic tube and a RF-tight extension tube. The matched device under test, DUT, which is fed by a generator forms the disturbing circuit which may also be designated as the inner or the primary circuit.
The disturbed circuit, which may also be designated as the outer or the second circuit, is formed by the outer conductor of the device under test, connected to the extension tube and a solid metallic tube having the DUT under test in its axis. The principle of the test set-up is shown in Figure 2 and Figure 3. The set-up is the same for measuring the transfer impedance and the screening attenuation or the coupling attenuation, where the length of the inner and the outer tube may vary. Generator Measuring tube Connector under test Receiver Extension tube Connecting cable Screening cap IEC
599/06 Figure 2 – Principle of the test set-up to measure transfer impedances
and screening or coupling attenuation of connectors Measuring tube Assembly under test Extension tube, variable length Connecting cable Screening cap Generator Connector interface Receiver IEC
600/06 Figure 3 – Principle of the test set-up to measure transfer impedances
and screening attenuation of short cable assemblies
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The voltage ratio of the voltage at the near end (U1) of the inner circuit (generator) and the voltage at the far end (U2) of the secondary circuit (receiver) shall be measured (U1/U2). The near end of the secondary circuit is short-circuited.
Depending on the electrical length of the the tested combination, the DUT and the extension tube, the result may be expressed either by the transfer impedance, the effective transfer impedance or the screening attenuation (or the coupling attenuation). For this measurement, a matched receiver is not necessary. The likely voltage peaks at the far end are not dependant on the input impedance of the receiver, provided that it is lower than the characteristic impedance of the secondary circuit. However, it is an advantage to have a low mismatch, for example by selecting a range of tube diameters for several sizes of coaxial cables. 5 Theoretical background See Annex A.6 Procedure 6.1 Equipment The principle of the test set-up is shown in Figure 2 and 3 and consists of: – an apparatus of a triple coaxial form with a length sufficient to produce a superimposition of waves in narrow frequency bands which enable the envelope curve to be drawn, – variable length of the tube, e.g. by different parts of the tube and/or by a movable tube in tube, – a RF-tight extension tube, variable in length, which should preferably have a diameter such that the characteristic impedance to the outer tube is 50 Ω or the nominal impedance of the network analyser or generator and receiver, – the material of the extension tube shall be non ferromagnetic and well conductive (copper or brass) and shall have a thickness ≥1 mm such that the transfer impedance is negligible compared to the transfer impedance of the device under test, – a signal generator with the same characteristic impedance as the cable under test or with an impedance adapter, completed by a power amplifier if necessary for very high screening attenuation, – a balun with sufficient unbalance attenuation, – a receiver with a calibrated step attenuator or a network analyser, (NWA). NOTEThe generator and the receiver may be included in a network analyser. 6.2 Connection between extension tube device under test The connection between the extension tube and the attached cables of the device under test shall be such that the contact resistance is negligible. A possible connection technique as well as the influence of contact resistances is given in Annex B.
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6.3 Dynamic range respectively noise floor With the verification test, the residual transfer impedance respectively the noise floor due to the connection of the feeding cable to the extension tube shall be determined. The feeding cable is matched with its characteristic impedance and connected to the test head. The extension tube shall then be connected to the feeding cable, using the same connection technique as during the test. The piece of cable between the connection points shall be as short as possible (see Figure 4). Generator Measuring tube Short cable piece,
RF-tight Receiver Extension tube High screened cable, e.g. semi rigid cable Screening cap IEC
601/06 Figure 4 – Principle set-up for verification test The voltage ratio U1/U2 shall be measured with the NWA. The noise floor of the connection of the extension tube to the feeding cable is then given by: ()2110/log20UUan×=(8) The residual transfer impedance of the connection of the extension tube to the feeding is given b
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