SIST HD 351.2 S1:2004

Rigid precision coaxial lines and their associated precision connectors - Part 2: 50 ohm 7 mm rigid precision coaxial line and associated hermaphroditic precision coaxial connector (IEC 60457-2:1974)

Describes the mechanical, electrical and environmental specifications of the 7 mm precision connector, the reflection coefficient and attenuation of which has to be measured up to 18 GHz.

Präzisionsrohrleitungen und zugehörige Präzisionssteckverbinder - Teil 2: 7 mm Präzisionskoaxialleitungen (50 Ohm) mit zugehöriger Präzisions-Zwittersteckverbindung (IEC 60457-2:1974)

Lignes coaxiales rigides de précision et leurs connecteurs de précision associés - Partie 2: 50 ohm 7 mm - Ligne coaxiale rigide de précision et connecteur coaxial de précision hermaphrodite associé (CEI 60457-2:1974)

Décrit les spécifications mécaniques, électriques et climatiques du connecteur de précision de 7 mm dont le coefficient de réflexion et l'affaiblissement doivent être mesurés jusqu'à 18 GHz.

[Not translated]

General Information

• Status: Published
• Publication Date: 07-Nov-2010
• ICS: 33.120.10 - Coaxial cables. Waveguides
• Technical Committee: iTEL - Communication cables
• Current Stage: 6660 - Retro National Implementation/Publication (Adopted Project)
• Start Date: 26-Oct-2010
• Due Date: 31-Dec-2010
• Completion Date: 08-Nov-2010
• Ref Project: HD 351.2 S1:1977 - Rigid precision coaxial lines and their associated precision connectors - Part 2: 50 ohm 7 mm rigid precision coaxial line and associated hermaphroditic precision coaxial connector

Overview

The SIST HD 351.2 S1:2004 standard, issued by the CLC (Chinese Lighting Committee) and originally based on IEC 60457-2:1974, defines the precise mechanical, electrical, and environmental requirements for the 50 ohm 7 mm rigid precision coaxial line and its associated hermaphroditic precision coaxial connector. Engineered for high-frequency applications, this standard covers the characteristics of coaxial connectors and lines with performance measurements extending up to 18 GHz. It ensures reliable, repeatable signal integrity and mechanical robustness for demanding telecommunications and RF systems.

Key Topics

• Mechanical Specifications

  • Nominal inner diameter of outer conductor: 7 mm
  • Center conductor nominal diameter: 3.040 mm
  • Tight manufacturing tolerances with deviations limited to ±0.005 mm on critical diameters
  • Hermaphroditic connectors featuring a coupling nut with minimum and maximum torque specifications
  • Contact force between mated connectors: 4.0 N to 9.0 N axial force on center conductor
  • Designed to withstand bending moments of up to 2 Nm without performance degradation
  • Mechanical endurance tested to 5,000 mating cycles with consistent electrical performance

• Electrical Characteristics

  • Characteristic impedance: 50 ohms, tightly controlled for impedance matching
  • Attenuation limits: Less than A = 7 - 3 √f (GHz) dB × 10 above 10 MHz
  • Reflection coefficient thresholds:
    • Connector pair: less than 0.0015 + 0.001 × (frequency in GHz)
    • Single connector: less than 0.0008 + 0.0005 × (frequency in GHz)
  • Contact resistances:
    • Center conductor ≤ 1 mΩ
    • Outer conductor ≤ 0.1 mΩ
  • Screening efficiency measured by transfer impedance to ensure minimal leakage, even under applied bending moments

• Environmental and Testing Conditions

  • Compliance with IEC Publication 68-1 environmental testing: dry heat, cold, and general conditions for telecommunication equipment
  • Operating temperature range: −55 °C to +70 °C
  • Electrical length accuracy must be within 0.05 mm to maintain measurement precision
  • Performance stability ensured under environmental stress and mechanical wear

Applications

This standard is critical for industries and applications requiring high-precision and reliable RF connections, including:

• Telecommunication Systems
  • High-frequency signal transmission lines
  • Measurement equipment with stringent reflection and attenuation criteria
• Aerospace and Defense
  • Radar and satellite communication systems where signal integrity must be preserved at GHz frequencies
• Test and Measurement Instruments
  • Calibration standards for vector network analyzers and similar devices
• Broadcasting and Wireless Infrastructure
  • Coaxial interconnects requiring hermaphroditic connectors for easy and reliable mating
• Research and Development
  • RF and microwave research facilities requiring consistent test cables with known, certified electrical parameters

Related Standards

• IEC 60457-2:1974 – The international equivalent and original basis for this standard, covering rigid precision coaxial lines and connectors
• IEC Publication 68-1 – Environmental testing procedures referenced for performance verification under varying climatic conditions
• HD 351.1 – Covers general requirements and measuring methods relevant to rigid precision coaxial lines
• Other 7 mm Coaxial Line Standards – Pertaining to alternate connector designs, impedance values, and flexible cable variants

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Keywords: 7 mm precision coaxial line, hermaphroditic coaxial connector, 50 ohm coaxial cable, rigid coaxial connectors, RF connectors, reflection coefficient, coaxial line attenuation, mechanical endurance coaxial, telecommunication connectors standard, IEC 60457, high frequency coaxial line, environmental testing coaxial connectors.

Standards Content (Sample)

SLOVENSKI STANDARD
01-januar-2004
[Not translated]
Rigid precision coaxial lines and their associated precision connectors - Part 2: 50 ohm 7
mm rigid precision coaxial line and associated hermaphroditic precision coaxial
connector (IEC 60457-2:1974)
Präzisionsrohrleitungen und zugehörige Präzisionssteckverbinder - Teil 2: 7 mm
Präzisionskoaxialleitungen (50 Ohm) mit zugehöriger Präzisions-Zwittersteckverbindung
(IEC 60457-2:1974)
Lignes coaxiales rigides de précision et leurs connecteurs de précision associés - Partie
2: 50 ohm 7 mm - Ligne coaxiale rigide de précision et connecteur coaxial de précision
hermaphrodite associé (CEI 60457-2:1974)
Ta slovenski standard je istoveten z: HD 351.2 S1:1977
ICS:
33.120.10 Koaksialni kabli. Valovodi Coaxial cables. Waveguides
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

NORME CE"
INTERNATIONALE IEC
60457-2
INTERNATIONAL
Première édition
STANDARD
First edition
1974-01
Lignes coaxiales rigides de précision
et leurs connecteurs de précision associés
Deuxième partie:
50 ohms 7 mm — Ligne coaxiale rigide de
précision et connecteur coaxial de précision
hermaphrodite associé
Rigid precision coaxial lines
and their associated precision connectors
Part 2:
50 ohm 7 mm rigid precision coaxial line
and associated hermaphroditic precision
coaxial connector
© IEC 1974 Droits de reproduction réservés — Copyright - all rights reserved
Aucune partie de cette publication ne peut être reproduite ni No part of this publication may be reproduced or utilized in
utilisée sous quelque forme que ce soit et par aucun any form or by any means, electronic or mechanical,
procédé, électronique ou mécanique, y compris la photo- including photocopying and microfilm, without permission in
copie et les microfilms, sans l'accord écrit de l'éditeur. writing from the publisher.
International Electrotechnical Commission 3, rue de Varembé Geneva, Switzerland
Telefax: [phone] e-mail: [e-mail] IEC web site http: //www.iec.ch
CODE PRIX
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Pour prix, voir catalogue en vigueur
• • For price, see current catalogue

INTERNATIONAL ELECTROTECHNICAL COMMISSION
COAXIAL LINES
RIGID PRECISION
AND THEIR ASSOCIATED PRECISION CONNECTORS
Part 2 : 50 ohm 7 mm rigid precision coaxial line
and associated hermaphroditic precision coaxial connector
FOREWORD
I) The formal decisions or agreements of the I E C on technical matters, prepared by Technical Committees on which all the
National Committees having a special interest therein are represented, express, as nearly as possible, an international
consensus of opinion on the subjects dealt with.
2) They have the form of recommendations for international use and they are accepted by the National Committees in that
sense.
3) In order to promote international unification, the I E C expresses the wish that all National Committees should adopt
the text of the I E C recommendation for their national rules in so far as national conditions will permit. Any divergence
between the I E C recommendations and the corresponding national rules should, as far as possible, be clearly
indicated in the latter.
PREFACE
This recommendation has been prepared by Sub-Committee 46D, Connectors for R.F. Cables, of I EC
Technical Committee No. 46, Cables, Wires and Waveguides for Telecommunication Equipment.
A first draft was discussed at the meeting held in The Hague in 1970. As a result of this meeting, a final
draft, document 46D(Central Office)2, was submitted to the National Committees for approval under the
Six Months' Rule in July 1971. Amendments, document 46D(Central Ofiîce)11, were submitted to the
National Committees for approval under the Two Months' Procedure in September 1972.
The following countries voted explicitly in favour of publication:
Australia Korea (Democratic People's
Belgium Republic of)
Czechoslovakia Netherlands
Denmark Poland
France Sweden
Germany Switzerland
Hungary Turkey
Israel United Kingdom
Italy United States of America
Japan
RIGID PRECISION COAXIAL LINES
AND THEIR ASSOCIATED PRECISION CONNECTORS
Part 2 : 50 ohm 7 mm rigid precision coaxial line
and associated hermaphroditic precision coaxial connector
Clause and
Sub-clause
Item
of IEC
Publication
457-1
3.1.7.2 Maximum frequency
The maximum frequency at which the reflection coefficient and attenuation are
measured is 18 GHz.
3.1.15 Electrical length
The electrical length, expressed in millimetres, of a connector pair shall be specified
by the manufacturer. The inaccuracy of the measurement shall be not more than
0.05 mm (0.002 in).
4. Type designation
Under consideration.
5. Standard atmospheric conditions for testing
Operating
The performance of the assemblies shall comply with the specified electrical require-
ments over the range of environmental conditions specified in I E C Publication
68-1, Basic Environmental Testing Procedures, Part 1: General, Sub-clause 4.3.
Environmental requirements
22.
Dry heat
23.
Cold
Non-operating
The performance of the assemblies shall remain within the electrical and mechanical
specifications when tested under normal operating conditions, after having been
exposed to the environmental conditions specified in I E C Publication 457-1, Rigid
Precision Coaxial Lines and their Associated Precision Connectors, Part 1: General
Requirements and Measuring Methods.
The following severities apply: Test A: — 55 °C; Test B: + 70 °C.
8. Dimensions
The inch dimensions are derived from the original millimetre dimensions.
The nominal inside diameter of the outer conductor shall be 7 mm (0.275 590 in).
Maximum deviations on the inner and outer diameters shall limit the uncertainty in
0.2 % or less, with a maximum deviation on the inside
the characteristic impedance to

Clause and
Sub-clause
of I EC
Item
Publication
457-1
diameter of the outer conductor of ± 0.005 mm (± 0.0002 in). The nominal outside
diameter of the centre conductor shall be 3.040 mm (0.119 685 in).
Dimensions shall also be checked after the tests according to I E C Publication 457-1,
Section Four, have been carried out.
For the critical dimensions of the mating faces, coupling attachment or coupling
means, refer to Figures 1, 2 and 3, pages 10, 11 and 12, respectively.
10.1 Centre contact force of mated hermaphroditic connectors
When two connectors are mated, the axial force exerted by the contact mechanism on
the centre conductor of a connector shall be max. 9.0 N and min. 4.0 N.
When a force of 18 N is applied for a least 12 h, the centre conductor of a connector
shall be displaced axially less th
...