SIST EN IEC 63138-4:2026
(Main)Multi-channel radio-frequency connectors - Part 4: Sectional specification for type L32-4 and L32-5 circular connectors (IEC 63138-4:2026)
Multi-channel radio-frequency connectors - Part 4: Sectional specification for type L32-4 and L32-5 circular connectors (IEC 63138-4:2026)
IEC 63138-4:2025, which is a Sectional Specification (SS), provides information and rules for the preparation of Detail Specifications (DS) for type L32-4 and L32-5 circular connectors with four RF channels and five RF channels, as well as a detailed specification of the blank format.
The L32-4 and L32-5 circular connectors with 50 Ω nominal impedance has four RF channels and five RF channels which can be engaged and disengaged at the same time. They are characterized by threaded coupling mechanisms, anti-misinsertion mechanism, and the operating frequency of each channel is up to 4 GHz. These connectors have been widely used in mobile communication system like TD-SCDMA and TD-LTE and can also be used in some similar equipment.
This document also specifies mating face dimensions for general connectors (grade 2), gauging information and tests selected from IEC 63138-1, applicable to all Detail Specifications relating to type L32 4 and L32-5 circular connectors.
This document cancels and replaces IEC 61169-59:2017.
This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to IEC 61169-59:2017:
a) use of IEC 63138-1:2019 as its generic specification instead of using IEC 61169-1:2013;
b) all the subclauses and test methods are in line with IEC 63138-1:2019;
c) dimension "g" in Table 3, Table 4, Table 7 and Table 8 has been changed from "0,00 min. to 0,8 max." to "1,6 min. to 2,1 max.".
Mehrkanalige Hochfrequenz-Steckverbinder – Teil 4: Rahmenspezifikation für Rundsteckverbinder der Typen L32-4 und L32-5 (IEC 63138-4:2026)
Connecteurs radiofréquences multicanaux - Partie 4: Spécification intermédiaire pour les connecteurs circulaires de type L32-4 et L32-5 (IEC 63138-4:2026)
L'IEC 63138-4:2026, qui est une spécification intermédiaire (SS, Sectional Specification), fournit des informations et des règles pour l'établissement de spécifications particulières (DS, Detail Specification) relatives aux connecteurs circulaires de type L32-4 et L32-5 avec quatre canaux RF et cinq canaux RF, ainsi que d'une spécification particulière-cadre.
Les connecteurs circulaires L32-4 et L32-5 avec une impédance nominale de 50 Ω comportent quatre canaux RF et cinq canaux RF qui peuvent être accouplés et désaccouplés simultanément. Ils sont caractérisés par des mécanismes de couplage filetés, un mécanisme anti-insertion incorrecte, et la fréquence de fonctionnement de chaque canal s'étend jusqu'à 4 GHz. Ces connecteurs sont couramment utilisés au sein de systèmes de communication mobile tels que TD-SCDMA et TD LTE, et peuvent également être utilisés dans d'autres matériels similaires.
Le présent document spécifie également les dimensions de la face d'accouplement pour les connecteurs à usage général (grade 2), les informations relatives au calibre et les essais choisis à partir de l'IEC 63138-1, applicables à toutes les spécifications particulières relatives aux connecteurs circulaires de type L32 4 et L32-5.
Cette édition annule et remplace l'IEC 61169-59:2017. Cette édition constitue une révision technique.
Cette édition inclut les modifications techniques majeures suivantes par rapport à l’IEC 61169-59:2017:
a) utilisation de l'IEC 63138-1:2019 comme spécification générique à la place de l'IEC 61169-1:2013;
b) tous les paragraphes et toutes les méthodes d'essai correspondent à ceux de l'IEC 63138-1:2019;
c) la dimension "g" dans le Tableau 3, le Tableau 4, le Tableau 7 et le Tableau 8 a été modifiée, passant de "0,00 min. à 0,8 max." à "1,6 min. à 2,1 max.".
Večkanalni radiofrekvenčni konektorji - 4. del: Področna specifikacija za okrogle konektorje vrste L32-4 in L32-5 (IEC 63138-4:2026)
General Information
- Status
- Published
- Public Enquiry End Date
- 31-Jul-2025
- Publication Date
- 19-Mar-2026
- Technical Committee
- MOC - Mobile Communications
- Current Stage
- 6060 - National Implementation/Publication (Adopted Project)
- Start Date
- 10-Mar-2026
- Due Date
- 15-May-2026
- Completion Date
- 20-Mar-2026
Relations
- Effective Date
- 01-May-2026
- Effective Date
- 20-Feb-2026
- Effective Date
- 03-Feb-2026
Overview
The standard kSIST FprEN IEC 63138-4:2025 titled Multi-channel Radio-Frequency Connectors - Part 4: Sectional Specification for Type L32-4 and L32-5 Circular Connectors is developed by the CLC under the International Electrotechnical Commission (IEC). This standard specifies the requirements for multi-coaxial radio-frequency (RF) connectors, particularly the threaded circular connectors of types L32-4 and L32-5 with 50Ω nominal impedance. It is designed to support operating frequencies up to 4 GHz.
These connectors are critical components used extensively in mobile communication systems such as TD-SCDMA and TD-LTE, as well as in similar high-frequency communication equipment. The specification covers mechanical dimensions, gauging, quality assessment, and testing requirements to ensure interoperability and reliable performance in RF applications.
Key Topics
Connector Types: The standard focuses on two types of circular multi-coaxial connectors:
- L32-4: Circular connectors with 4 pin or socket contacts.
- L32-5: Circular connectors with 5 pin or socket contacts.
Mating Face and Dimensions:
- Detailed dimensions of the mating faces for both L32-4 and L32-5 connector variants.
- Specification of pin and socket contact arrangements, including anti-mismating mechanisms.
- Precise dimensional tables and figures defining features such as main grooves, supplementary grooves, and sealing ring shapes to ensure proper connector mating.
Gauging Information:
- Definition of gauges for socket and pin contacts to verify compatibility.
- Guidelines for the use of gauges in quality control processes.
Quality Assessment:
- Procedures for inspection, including lot-by-lot and periodic inspections.
- Criteria for mechanical compatibility, electrical performance, and return loss.
- Rating and characteristics vital for ensuring compliance with the standard.
Test Procedures:
- Selection of test methods aligned with IEC 63138-1:2019 generic specifications.
- Tests focus on mechanical, electrical, and environmental performance.
- Emphasis on preventing mismating through the use of anti-mismating features.
Detail Specifications Preparation:
- Instructions and proforma for manufacturers to prepare detailed component specifications.
- Marking, ordering information, and packaging details ensuring traceability and standard compliance.
Applications
The IEC 63138-4 standard has practical applications across various sectors where reliable high-frequency multi-channel RF connections are vital:
- Mobile Communication Systems: Especially suited for TD-SCDMA and TD-LTE base stations and related infrastructure where robust multi-coaxial connectors are essential.
- Wireless Equipment: Devices demanding precise RF signal transmission through multi-channel connections can benefit from the defined connector specifications.
- Test and Measurement Instruments: Ensures standard interface compatibility for RF test devices.
- Aerospace and Defense: Where secure and reliable RF connections are critical for communication and signal integrity.
- Industrial RF Communication: Reliable connectors that do not compromise on signal quality and mechanical stability in harsh environments.
Related Standards
This specification is part 4 of the IEC 63138 series focusing on multi-channel radio-frequency connectors and builds upon the following:
- IEC 63138-1:2019: Generic specification providing general requirements and test methods for multi-channel RF connectors.
- Supersedes and replaces IEC 61169-59:2017, introducing technical updates aligned with modern RF connector requirements.
- The document aligns with ISO/IEC Directives for consistency in international standardization.
- Cross-referenced with normative documents and terminological databases such as IEC Electropedia and ISO Online Browsing Platform for harmonized definitions.
Summary
The kSIST FprEN IEC 63138-4:2025 standard is a critical document that defines sectional specifications for L32-4 and L32-5 circular multi-coaxial RF connectors up to 4 GHz. It ensures interoperability, high-performance mechanical and electrical characteristics, and reliable mating mechanisms with anti-mismating features. Widely applied in mobile telecommunication and other RF communication equipment, this standard supports manufacturers and users by providing detailed dimensional, testing, and quality guidelines to uphold consistency and quality in RF connector deployment.
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Frequently Asked Questions
SIST EN IEC 63138-4:2026 is a standard published by the Slovenian Institute for Standardization (SIST). Its full title is "Multi-channel radio-frequency connectors - Part 4: Sectional specification for type L32-4 and L32-5 circular connectors (IEC 63138-4:2026)". This standard covers: IEC 63138-4:2025, which is a Sectional Specification (SS), provides information and rules for the preparation of Detail Specifications (DS) for type L32-4 and L32-5 circular connectors with four RF channels and five RF channels, as well as a detailed specification of the blank format. The L32-4 and L32-5 circular connectors with 50 Ω nominal impedance has four RF channels and five RF channels which can be engaged and disengaged at the same time. They are characterized by threaded coupling mechanisms, anti-misinsertion mechanism, and the operating frequency of each channel is up to 4 GHz. These connectors have been widely used in mobile communication system like TD-SCDMA and TD-LTE and can also be used in some similar equipment. This document also specifies mating face dimensions for general connectors (grade 2), gauging information and tests selected from IEC 63138-1, applicable to all Detail Specifications relating to type L32 4 and L32-5 circular connectors. This document cancels and replaces IEC 61169-59:2017. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to IEC 61169-59:2017: a) use of IEC 63138-1:2019 as its generic specification instead of using IEC 61169-1:2013; b) all the subclauses and test methods are in line with IEC 63138-1:2019; c) dimension "g" in Table 3, Table 4, Table 7 and Table 8 has been changed from "0,00 min. to 0,8 max." to "1,6 min. to 2,1 max.".
IEC 63138-4:2025, which is a Sectional Specification (SS), provides information and rules for the preparation of Detail Specifications (DS) for type L32-4 and L32-5 circular connectors with four RF channels and five RF channels, as well as a detailed specification of the blank format. The L32-4 and L32-5 circular connectors with 50 Ω nominal impedance has four RF channels and five RF channels which can be engaged and disengaged at the same time. They are characterized by threaded coupling mechanisms, anti-misinsertion mechanism, and the operating frequency of each channel is up to 4 GHz. These connectors have been widely used in mobile communication system like TD-SCDMA and TD-LTE and can also be used in some similar equipment. This document also specifies mating face dimensions for general connectors (grade 2), gauging information and tests selected from IEC 63138-1, applicable to all Detail Specifications relating to type L32 4 and L32-5 circular connectors. This document cancels and replaces IEC 61169-59:2017. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to IEC 61169-59:2017: a) use of IEC 63138-1:2019 as its generic specification instead of using IEC 61169-1:2013; b) all the subclauses and test methods are in line with IEC 63138-1:2019; c) dimension "g" in Table 3, Table 4, Table 7 and Table 8 has been changed from "0,00 min. to 0,8 max." to "1,6 min. to 2,1 max.".
SIST EN IEC 63138-4:2026 is classified under the following ICS (International Classification for Standards) categories: 33.120.30 - RF connectors. The ICS classification helps identify the subject area and facilitates finding related standards.
SIST EN IEC 63138-4:2026 has the following relationships with other standards: It is inter standard links to SIST EN 61169-59:2018, SIST EN IEC 63138-1:2020, SIST EN IEC 60966-4-4:2026. Understanding these relationships helps ensure you are using the most current and applicable version of the standard.
SIST EN IEC 63138-4:2026 is available in PDF format for immediate download after purchase. The document can be added to your cart and obtained through the secure checkout process. Digital delivery ensures instant access to the complete standard document.
Standards Content (Sample)
SLOVENSKI STANDARD
01-maj-2026
Nadomešča:
SIST EN 61169-59:2018
Večkanalni radiofrekvenčni konektorji - 4. del: Področna specifikacija za okrogle
konektorje vrste L32-4 in L32-5 (IEC 63138-4:2026)
Multi-channel radio-frequency connectors - Part 4: Sectional specification for type L32-4
and L32-5 circular connectors (IEC 63138-4:2026)
Mehrkanalige Hochfrequenz-Steckverbinder – Teil 4: Rahmenspezifikation für
Rundsteckverbinder der Typen L32-4 und L32-5 (IEC 63138-4:2026)
Connecteurs radiofréquences multicanaux - Partie 4: Spécification intermédiaire pour les
connecteurs circulaires de type L32-4 et L32-5 (IEC 63138-4:2026)
Ta slovenski standard je istoveten z: EN IEC 63138-4:2026
ICS:
33.120.30 Radiofrekvenčni konektorji RF connectors
(RF)
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
EUROPEAN STANDARD EN IEC 63138-4
NORME EUROPÉENNE
EUROPÄISCHE NORM March 2026
ICS 33.120.30 Supersedes EN 61169-59:2017
English Version
Multi-channel radio-frequency connectors - Part 4: Sectional
specification for type L32-4 and L32-5 circular connectors
(IEC 63138-4:2026)
Connecteurs radiofréquences multicanaux - Partie 4: Mehrkanalige Hochfrequenz-Steckverbinder - Teil 4:
Spécification intermédiaire pour les connecteurs circulaires Rahmenspezifikation für Rundsteckverbinder der Typen
de type L32-4 et L32-5 L32-4 und L32-5
(IEC 63138-4:2026) (IEC 63138-4:2026)
This European Standard was approved by CENELEC on 2026-02-24. 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 CEN-CENELEC
Management Centre 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 CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Türkiye and the United Kingdom.
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2026 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 63138-4:2026 E
European foreword
The text of document 46F/730/FDIS, future edition 1 of IEC 63138-4, prepared by SC 46F "RF and
microwave passive components" of IEC/TC 46 "Cables, wires, waveguides, RF connectors, RF and
microwave passive components and accessories" was submitted to the IEC-CENELEC parallel vote
and approved by CENELEC as EN IEC 63138-4:2026.
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2027-03-31
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2029-03-31
document have to be withdrawn
This document supersedes EN 61169-59:2017 and all of its amendments and corrigenda (if any).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.
Any feedback and questions on this document should be directed to the users’ national committee. A
complete listing of these bodies can be found on the CENELEC website.
Endorsement notice
The text of the International Standard IEC 63138-4:2026 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following note has to be added for the standard indicated:
IEC 61169-1:2013 NOTE Approved as EN 61169-1:2013 (not modified)
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements 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 1 Where an International Publication has been modified by common modifications, indicated by (mod),
the relevant EN/HD applies.
NOTE 2 Up-to-date information on the latest versions of the European Standards listed in this annex is available
here: www.cencenelec.eu.
Publication Year Title EN/HD Year
IEC 63138-1 2019 Multi-channel radio frequency connectors - EN IEC 63138-1 2019
Part 1: Generic specification - General
requirements and test methods
IEC 63138-4 ®
Edition 1.0 2026-01
INTERNATIONAL
STANDARD
Multi-channel radio-frequency connectors -
Part 4: Sectional specification for type L32-4 and L32-5 circular connectors
ICS 33.120.30 ISBN 978-2-8327-0993-1
IEC 63138-4:2026-01(en)
IEC 63138-4:2026 © IEC 2026
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Mating face and gauge information . 5
4.1 Mating face dimensions . 5
4.1.1 Connector with pin contact. 5
4.1.2 Connector with socket contact . 8
4.1.3 Mating face of RF channel . 10
4.2 Gauges . 11
4.2.1 Gauge for socket centre contact . 11
4.2.2 Gauge for L32-5 connector with 5 pin contacts . 12
4.2.3 Gauge for L32-4 connector with 4 pin contacts . 13
4.2.4 Gauge for L32-5 connector with 5 socket contacts . 14
4.2.5 Gauge for L32-4 connector with 4 socket contacts . 15
5 Quality assessment procedure . 16
5.1 General . 16
5.2 Rating and characteristics . 16
5.3 Quality assessment . 18
5.3.1 General . 18
5.3.2 Inspection procedure . 18
5.3.3 Lot-by-lot inspection . 19
5.3.4 Periodic inspections. 20
6 Instructions for preparation of detail specifications . 21
6.1 General . 21
6.2 Identification of the component . 21
6.3 Performance . 21
6.4 Marking, ordering information and related matters . 22
6.5 Selection of tests, test conditions and severities . 22
6.6 Blank Detail Specification pro forma for L32 series circular connector . 23
7 Marking . 26
7.1 Marking of component . 26
7.2 Marking and contents of package . 27
Bibliography . 28
Figure 1 – L32-5 connector with 5 pin contacts . 6
Figure 2– L32-4 connector with 4 pin contacts . 7
Figure 3 – L32-5 connector with 5 socket contacts . 8
Figure 4 – L32-4 Connector with 4 socket contacts . 9
Figure 5 – Mating face of RF channel . 10
Figure 6 – Gauge for socket contact of RF channel . 11
Figure 7 – Gauge for L32-5 connector with 5 pin contacts . 12
Figure 8 – Gauge for L32-4 connector with 4 pin contacts . 13
Figure 9 – Gauge for L32-5 connector with 5 socket contacts . 14
IEC 63138-4:2026 © IEC 2026
Figure 10 – Gauge for L32-4 connector with 4 socket contacts . 15
Table 1 – Dimensions of L32-5 connector with 5 pin contacts . 6
Table 2 – Dimensions of L32-4 connector with 4 pin contacts . 7
Table 3 – Dimensions of L32-5 connector with 5 socket contacts . 8
Table 4 – Dimensions of L32-4 connector with 4 socket contacts . 9
Table 5 – Dimensions of the mating face of RF channel . 10
Table 6 – Dimensions of gauge for socket contact . 11
Table 7 – Dimensions of gauge for L32-5 connector with 5 pin contacts . 12
Table 8 – Dimensions of gauge for L32-4 connector with 4 pin contacts . 13
Table 9 – Dimensions of gauge for L32-5 connector with 5 socket contacts . 14
Table 10 – Dimensions of gauge for L32-4 connector with 4 socket contacts . 15
Table 11 – Rating and characteristics . 16
Table 12 – Qualification inspection . 18
Table 13 – Lot-by-lot inspection . 19
Table 14 – Sampling plans for mechanical compatibility and return loss inspection . 20
Table 15 – Periodic inspection . 20
IEC 63138-4:2026 © IEC 2026
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
Multi-channel radio-frequency connectors -
Part 4: Sectional specification for type L32-4 and L32-5 circular
connectors
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 itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
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) and
expenses 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) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). IEC takes no position concerning the evidence, validity or applicability of any claimed patent rights in
respect thereof. As of the date of publication of this document, IEC had not received notice of (a) patent(s), which
may be required to implement this document. However, implementers are cautioned that this may not represent
the latest information, which may be obtained from the patent database available at https://patents.iec.ch. IEC
shall not be held responsible for identifying any or all such patent rights.
IEC 63138-4 has been prepared by subcommittee 46F: RF and microwave passive components,
of IEC technical committee 46: Cables, wires, waveguides, RF connectors, RF and microwave
passive components and accessories. It is an International Standard.
This edition cancels and replaces IEC 61169-59:2017. This edition constitutes a technical
revision.
This edition includes the following significant technical changes with respect to
IEC 61169-59:2017:
a) use of IEC 63138-1:2019 as its generic specification instead of using IEC 61169-1:2013;
b) all the subclauses and test methods are in line with IEC 63138-1:2019;
c) dimension "g" in Table 3, Table 4, Table 7 and Table 8 has been changed from "0,00 min.
to 0,8 max." to "1,6 min. to 2,1 max.".
IEC 63138-4:2026 © IEC 2026
The text of this International Standard is based on the following documents:
Draft Report on voting
46F/XX/FDIS 46F/XX/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
A list of all parts in the IEC 63138 series, published under the general title Multi-channel radio-
frequency connectors, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
– reconfirmed,
– withdrawn, or
– revised.
IEC 63138-4:2026 © IEC 2026
1 Scope
This part of IEC 63138, which is a Sectional Specification (SS), provides information and rules
for the preparation of Detail Specifications (DS) for type L32-4 and L32-5 circular connectors
with four RF channels and five RF channels, as well as a detailed specification of the blank
format.
The L32-4 and L32-5 circular connectors with 50 Ω nominal impedance has four RF channels
and five RF channels which can be engaged and disengaged at the same time. They are
characterized by threaded coupling mechanisms, anti-misinsertion mechanism, and the
operating frequency of each channel is up to 4 GHz. These connectors have been widely used
in mobile communication system like TD-SCDMA and TD-LTE and can also be used in some
similar equipment.
This document also specifies mating face dimensions for general connectors (grade 2), gauging
information and tests selected from IEC 63138-1, applicable to all Detail Specifications relating
to type L32-4 and L32-5 circular connectors.
NOTE Metric dimension are original dimensions. All undimensioned pictorial configurations are for reference
purpose only.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements 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 63138-1:2019, Multi-channel radio frequency connectors - Part 1: Generic specification -
General requirements and test methods
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 63138-1 apply.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
– IEC Electropedia: available at https://www.electropedia.org/
– ISO Online browsing platform: available at https://www.iso.org/obp
4 Mating face and gauge information
4.1 Mating face dimensions
4.1.1 Connector with pin contact
4.1.1.1 L32-5 connector with 5 pin contacts
The mating face of L32-5 connector with 5 pin contacts is shown in Figure 1 and its dimensions
are shown in Table 1.
IEC 63138-4:2026 © IEC 2026
NOTE 1 Mechanical and electrical reference plane.
NOTE 2 Chamfer of the three supplementary grooves is optional.
NOTE 3 The mating face of RF channel with pin contact is shown in Figure 5 a) and its dimensions are shown in
Table 5.
NOTE 4 The shape of seal ring is optional.
NOTE 5 Anti-mismating pin.
NOTE 6 The initial position number of the RF channel with pin contact and the other positions numbered clockwise.
Figure 1 – L32-5 connector with 5 pin contacts
Table 1 – Dimensions of L32-5 connector with 5 pin contacts
Dimensions
Ref. mm
Min. Max.
a 6,0 6,1
b 6,0 6,2
c 7,5 7,6
d M32X1,5-6g
e 14,4 14,5
f 6,0 --
g 9,5 9,7
h 24,0 --
k 27,0 27,1
m 2,1 2,2
n 16,5
4.1.1.2 L32-4 connector with 4 pin contacts
The mating face of L32-4 connector with 4 pin contacts is shown in Figure 2 and its dimensions
are shown in Table 2.
IEC 63138-4:2026 © IEC 2026
NOTE 1 Mechanical and electrical reference plane.
NOTE 2 Chamfer of the three supplementary grooves is optional.
NOTE 3 The mating face of RF channel with pin contact is shown in Figure 5 a) and its dimensions are shown in
Table 5.
NOTE 4 The shape of seal ring is optional.
NOTE 5 Anti-mismating pin.
NOTE 6 The initial position number of the RF channel with pin contact and the other positions are numbered
anticlockwise.
Figure 2– L32-4 connector with 4 pin contacts
Table 2 – Dimensions of L32-4 connector with 4 pin contacts
Dimensions
Ref. mm
Min. Max.
a 6,0 6,1
b 6,0 6,2
c 7,5 7,6
d M32X1,5-6g
e 14,4 14,5
f 6,0 --
g 9,5 9,7
h 24,0 --
k 27,0 27,1
m 2,1 2,2
n 16,5
IEC 63138-4:2026 © IEC 2026
4.1.2 Connector with socket contact
4.1.2.1 L32-5 connector with 5 socket contacts
The mating face of L32-5 connector with 5 socket contacts is shown in Figure 3 and its
dimensions are shown in Table 3.
NOTE 1 Mechanical and electrical reference plane.
NOTE 2 The mating face of RF channel with socket contact is shown in Figure 5 b) and its dimensions are shown
as Table 5.
NOTE 3 Anti-mismating socket.
NOTE 4 The shape of main keys is optional.
NOTE 5 The initial position number of the RF channel with socket contact and the other positions are numbered
anticlockwise.
Figure 3 – L32-5 connector with 5 socket contacts
Table 3 – Dimensions of L32-5 connector with 5 socket contacts
Dimensions
mm
Ref.
Max.
Min.
6,35
6,25
a
--
7,0
b
7,8
7,7
c
M32 ×1,5-7 H
d
14,3
14,2
e
8,0
7,6
f
2,1
1,6
g
--
6,8
h
0,3
0,08
i
11,7
11,5
j
26,7
26,6
k
35,0
34,9
l
2,0
1,9
m
16,5
n
6,1
5,8
p
IEC 63138-4:2026 © IEC 2026
4.1.2.2 L32-4 connector with 4 socket contacts
The mating face of L32-4 connector with 4 socket contacts is shown in Figure 4 and its
dimensions are shown in Table 4.
NOTE 1 Mechanical and electrical reference plane.
NOTE 2 The mating face of RF channel with socket contact is shown in Figure 5 b) and its dimensions are shown
in Table 5.
NOTE 3 Anti-mismating socket.
NOTE 4 The shape of main keys is optional.
NOTE 5 The initial position number of the RF channel with socket contact and the other positions are numbered
anticlockwise.
Figure 4 – L32-4 Connector with 4 socket contacts
Table 4 – Dimensions of L32-4 connector with 4 socket contacts
Dimensions
mm
Ref.
Max.
Min.
6,35
6,25
a
--
7,0
b
7,8
7,7
c
M32 ×1,5-7 H
d
14,3
14,2
e
8,0
7,6
f
2,1
1,6
g
--
6,8
h
0,3
0,08
i
11,7
11,5
j
26,7
26,6
k
35,0
34,9
l
2,0
1,9
m
16,5
n
6,1
5,8
p
IEC 63138-4:2026 © IEC 2026
4.1.3 Mating face of RF channel
The mating face of the RF
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