SIST EN 16602-70-18:2015

Space product assurance - Preparation, assembly and mounting of RF coaxial cables

This Standard defines the technical requirements and quality assurance provisions for the assembly and mounting of high­reliability, radio­frequency (RF) coaxial­cable interconnections for use as transmission lines in spacecraft and associated equipment.
In general, these assemblies are designed for low­loss, stable operation from the relatively low frequencies through the higher frequencies
in the microwave regions.
These transmission­line cables should not be confused with low­frequency cables with conductive sheaths (usually copper braid), which are used in applications where shielding of the centre conductors from the surrounding electrical ambient is required. The interconnection of
those shielded cables, not covered by the present standard, is covered in ECSS-Q-ST-70-08.
This standard may be tailored for the specific characteristics and constrains of a space project in conformance with ECSS-S-ST-00.

Raumfahrtproduktsicherung - Vorbereitung, Zusammenbau und Befestigung von RF-Koaxial-Kabeln

Assurance produit des projets spatiaux - Préparation, assemblage et montage des câbles radiofréquence coaxiaux

La présente norme définit les exigences techniques et les dispositions d’assurance qualité relatives à l'assemblage et au montage d'interconnexions en câble coaxial radiofréquences (RF) destinées à servir de lignes de transmission à bord d'engins spatiaux et d'équipements associés.
En général, ces ensembles sont conçus pour un fonctionnement stable, à faibles pertes, allant de fréquences relativement basses jusqu'à des fréquences plus élevées dans la gamme des micro-ondes.
Il convient de ne pas confondre ces câbles de ligne de transmission avec les câbles basse fréquence à gaines conductrices (en général une tresse de cuivre), utilisés dans les applications où il est exigé de disposé d'un blindage des conducteurs centraux pour les isoler de l'environnement électrique ambiant. L'interconnexion de ces câbles blindés, non couverte par la présente norme, est traitée dans l'ECSS-Q-ST-70-08.
La présente norme peut être adaptée aux caractéristiques et contraintes spécifiques à un projet spatial, selon la norme ECSS-S-ST-00.

Zagotavljanje varnih proizvodov v vesoljski tehniki - Pripravljanje, sestavljanje in pritrjevanje RF-koaksialnih kablov

Ta standard določa tehnične zahteve in določbe za zagotavljanje kakovosti za sestavljanje in pritrjevanje visoko zanesljivih medsebojnih povezav z RF-koaksialnimi kabli za uporabo kot prenosni vodi v vesoljskih plovilih ter povezani opremi. Na splošno so ti sestavi namenjeni za stabilno delovanje z majhnimi izgubami od razmeroma nizkih frekvenc prek višjih frekvenc v mikrovalovnih regijah. Ti kabli za prenosne vode naj se ne bi zamenjali z nizkofrekvenčnimi kabli s prevodnimi plašči (običajno bakreni oplet), ki se uporabljajo, kadar je potrebno ščitenje središčnih vodnikov pred bližnjo električno okolico. Medsebojno povezovanje teh zaščitenih kablov, ki ni obravnavano v tem standardu, je obravnavajo v standardu ECSS-Q-ST-70-08. Ta standard se lahko prilagodi posameznim lastnostim in omejitvam vesoljskega projekta v skladu s standardom ECSS-S-ST-00.

General Information

• Status: Published
• Public Enquiry End Date: 27-Feb-2014
• Publication Date: 01-Dec-2014
• ICS: 49.060 - Aerospace electric equipment and systems
• Technical Committee: I13 - Imaginarni 13
• Current Stage: 6060 - National Implementation/Publication (Adopted Project)
• Start Date: 06-Nov-2014
• Due Date: 11-Jan-2015
• Completion Date: 02-Dec-2014
• Mandate: M/496 - Mandate addressed to CEN, CENELEC and ETSI to develop standardisation regarding space industry (Phase 3 of the process)
• Ref Project: EN 16602-70-18:2014 - Space product assurance - Preparation, assembly and mounting of RF coaxial cables

Overview - EN 16602-70-18:2014 (Space product assurance)

EN 16602-70-18:2014 is a CEN European Standard that defines technical requirements and quality‑assurance provisions for preparing, assembling and mounting high‑reliability RF coaxial cable interconnections used as transmission lines in spacecraft and associated equipment. The standard focuses primarily on semi‑rigid coaxial cables intended for low‑loss, stable operation from low frequencies through microwave regions. It distinguishes these transmission‑line cables from low‑frequency shielded cables (see ECSS‑Q‑ST‑70‑08) and may be tailored for specific space projects in conformance with ECSS‑S‑ST‑00.

Key topics and technical requirements

The standard provides practical process and workmanship controls across the full assembly lifecycle. Major topics include:

• Preparatory conditions: facility cleanliness, environmental controls, lighting and tooling requirements for reliable cable work.
• Material selection: approved choices and controls for solder, flux, solvents, cable and connector selection suited to low‑outgassing space environments.
• Cable preparation: cutting to oversize, forming (minimum bend radius), preconditioning heat treatment, trimming and precise stripping of semi‑rigid cable ends.
• Assembly methods: detailed guidance for soldered and crimped terminations, solder preforms, degolding/pretinning and acceptable connector assemblies. Alternative coaxial technologies are recognised with general requirements.
• Mounting: recommended practices for securing straight and right‑angle connectors, avoiding mechanical stress and ensuring electrical integrity.
• Process verification and environmental testing: temperature cycling and vibration verification to confirm durability across the specified operational range (typical −45 °C to +85 °C).
• Quality assurance: traceability, calibration, inspection, nonconformance control, operator training and workmanship standards (annexes include logbook and workmanship illustrations).

Applications and users

EN 16602‑70‑18 is used by:

• Satellite and spacecraft system engineers and RF/harness designers specifying transmission‑line interconnects.
• Assembly/qualification technicians performing soldering, crimping and cable mounting operations.
• Quality assurance and supplier control teams enforcing traceability, environmental screening and process verification.
• Procurement and manufacturing of antenna feeds, payload RF links, microwave distribution networks, and communications subsystems where high reliability and low loss are critical.

Practical benefits include reduced RF losses, stable VSWR performance, mechanical robustness under launch and space environments, and compliant documentation for project audits.

Related standards

• ECSS‑Q‑ST‑70‑08 (manual soldering of high‑reliability electrical connections)
• ECSS‑Q‑ST‑70‑26 (crimping)
• ECSS‑S‑ST‑00 (tailoring rules)
• MIL‑C‑17G (RF cable general specification - historical reference)

Keywords: EN 16602‑70‑18:2014, space product assurance, RF coaxial cables, semi‑rigid coaxial, soldering, crimping, cable assembly, spacecraft RF transmission lines, low‑loss microwave.

Standards Content (Sample)

SLOVENSKI STANDARD
01-januar-2015
Zagotavljanje varnih proizvodov v vesoljski tehniki - Pripravljanje, sestavljanje in
pritrjevanje RF-koaksialnih kablov
Space product assurance - Preparation, assembly and mounting of RF coaxial cables
Raumfahrtproduktsicherung - Vorbereitung, Zusammenbau und Befestigung von RF-
Koaxial-Kabeln
Assurance produit des projets spatiaux - Préparation, assemblage et montage des
câbles radiofréquence coaxiaux
Ta slovenski standard je istoveten z: EN 16602-70-18:2014
ICS:
49.060 /HWDOVNDLQYHVROMVND Aerospace electric
HOHNWULþQDRSUHPDLQVLVWHPL equipment and systems
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN 16602-70-18
NORME EUROPÉENNE
EUROPÄISCHE NORM
October 2014
ICS 49.090; 49.140
English version
Space product assurance - Preparation, assembly and mounting
of RF coaxial cables
Assurance produit des projets spatiaux - Préparation, Raumfahrtproduktsicherung - Vorbereitung, Zusammenbau
assemblage et montage des câbles radiofréquence und Befestigung von RF-Koaxial-Kabeln
coaxiaux
This European Standard was approved by CEN on 11 April 2014.

CEN and 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 CEN and 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 CEN and CENELEC member into its own language and notified to the CEN-CENELEC Management Centre
has the same status as the official versions.

CEN and CENELEC members are the national standards bodies and national electrotechnical committees of Austria, Belgium, Bulgaria,
Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece,
Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania, Slovakia,
Slovenia, Spain, Sweden, Switzerland, Turkey and United Kingdom.

CEN-CENELEC Management Centre:
Avenue Marnix 17, B-1000 Brussels
© 2014 CEN/CENELEC All rights of exploitation in any form and by any means reserved Ref. No. EN 16602-70-18:2014 E
worldwide for CEN national Members and for CENELEC
Members.
Table of contents
Foreword . 5
Introduction . 6
1 Scope . 7
2 Normative references . 8
3 Terms, definitions and abbreviated terms . 9
3.1 Terms from other standards . 9
3.2 Terms specific to the present standard . 9
3.3 Abbreviated terms. 9
4 Principles and prerequisites of reliable soldered or crimped cable
connections . 10
4.1 Principles of reliable soldered or crimped semi-rigid cable connections . 10
4.2 Prerequisites for assembly and mounting of semi-rigid coaxial cables . 10
4.3 Alternative coaxial cable technologies . 11
5 Requirements . 12
5.1 Preparatory conditions . 12
5.1.1 Facility cleanliness . 12
5.1.2 Environmental conditions . 12
5.1.3 Lighting requirements . 13
5.1.4 Equipment and tools . 13
5.2 Material selection . 15
5.2.1 Solder . 15
5.2.2 Flux . 16
5.2.3 Solvents . 16
5.2.4 Cable selection . 17
5.2.5 Connector selection . 17
5.3 Preparation of semi-rigid cable . 18
5.3.1 General . 18
5.3.2 Inspection of cable . 18
5.3.3 Cutting cable to initial oversize length . 18
5.3.4 Cable forming and minimum bend radius . 18
5.3.5 Preconditioning heat treatment. 19
5.3.6 Trimming cable to final length . 20
5.3.7 Stripping the cable ends . 21
5.3.8 Inspection of stripped cable ends . 21
5.4 Preparation for soldering assembly of semi-rigid cables . 22
5.4.1 General . 22
5.4.2 Degolding and pretinning . 22
5.4.3 Solder preforms . 23
5.5 Assembly of connectors to RF coaxial cables . 24
5.5.1 Solder assembly of semi-rigid cables . 24
5.5.2 Crimp assembly of semi-rigid cables and other assembly techniques . 28
5.5.3 Completed assemblies . 28
5.6 Mounting of cables. 29
5.6.1 Semi-rigid cables with straight solder-type connectors . 29
5.6.2 Semi-rigid cables with right-angle connectors . 30
5.6.3 Other cable mounting technologies . 30
5.7 Process verification . 31
5.7.1 General . 31
5.7.2 Temperature cycling . 31
5.7.3 Vibration . 31
5.8 Quality assurance . 31
5.8.1 Data . 31
5.8.2 Nonconformance . 32
5.8.3 Calibration . 32
5.8.4 Traceability . 32
5.8.5 Workmanship standards. 32
5.8.6 Inspection . 32
5.8.7 Operator and inspector training and certification . 33
Annex A (normative) Logbook – DRD . 34
A.1 DRD identification . 34
A.1.1 Requirement identification and source document . 34
A.1.2 Purpose and objective . 34
A.2 Expected response . 34
A.2.1 Scope and content . 34
A.2.2 Special remarks . 34
Annex B (normative) Workmanship standards . 35
B.1 Overview . 35
B.2 Illustrations . 35
Annex C (informative) Graphical information . 37
C.1 Overview . 37
C.2 Typical cable cut-off fixture . 37
C.3 Typical cable-forming tool . 38
C.4 Approved and non-approved straight solder-type cable-end connectors . 39
C.5 Method of producing solder performs. 40
C.6 Centre contact assembly . 40
Bibliography . 41

Figures
Figure B-1 : Photograph showing non-captive nut and preferred solder fillet . 35
Figure B-2 : Microsection through preferred solder fillet, revealing full penetration of
solder path . 35
Figure B-3 : Unacceptable solder fillet dimensions . 36
Figure C-1 : Typical cable cut-off fixture . 37
Figure C-2 : Typical cable-forming tool . 38
Figure C-3 : Approved and non-approved straight solder-type cable-end connectors . 39
Figure C-4 : Method of producing solder preforms . 40
Figure C-5 : Centre contact assembly . 40

Tables
Table 5-1: Design rules for minimum bend radius . 19
Table 5-2: Preconditioning heat treatment process . 20

Foreword
This document (EN 16602-70-18:2014) has been prepared by Technical
Committee CEN/CLC/TC 5 “Space”, the secretariat of which is held by DIN.
This standard (EN 16602-70-18:2014) originates from ECSS-Q-ST-70-18C.
This European Standard shall be given the status of a national standard, either
by publication of an identical text or by endorsement, at the latest by April 2015,
and conflicting national standards shall be withdrawn at the latest by April
2015.
Attention is drawn to the possibility that some of the elements of this document
may be the subject of patent rights. CEN [and/or CENELEC] shall not be held
responsible for identifying any or all such patent rights.
This document has been prepared under a mandate given to CEN by the
European Commission and the European Free Trade Association.
This document has been developed to cover specifically space systems and has
therefore precedence over any EN covering the same scope but with a wider
domain of applicability (e.g. : aerospace).
According to the CEN-CENELEC Internal Regulations, the national standards
organizations of the following countries are bound to implement this European
Standard: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic,
Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France,
Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania,
Luxembourg, Malta, Netherlands, Norway, Poland, Portugal, Romania,
Slovakia, Slovenia, Spain, Sweden, Switzerland, Turkey and the United
Kingdom.
Introduction
The main part of this Standard is based on industrial experience and
recommendations from European soldering technology experts. Modifications
are incorporated into the text to provide for the specific requirement of
low-outgassing electrical systems which are required by scientific and
application satellites. Other additions were made in the light of recent
technological advances and results of metallurgical test programmes. The use of
processes other than solder assembly is recognized, but only certain general
requirements are given in this Standard.
These requirements apply to assemblies designed to operate within the
temperature limits from -45 °C to +85 °C. More extreme temperatures or other
unusual environmental applications require special design measures or
processing steps to provide environmental survival capability.
Scope
This Standard defines the technical requirements and quality assurance
provisions for the assembly and mounting of high-reliability, radio-frequency
(RF) coaxial-cable interconnections for use as transmission lines in spacecraft
and associated equipment.
In general, these assemblies are designed for low-loss, stable operation from the
relatively low frequencies through the higher frequencies in the microwave
regions.
These transmission-line cables should not be confused with low-frequency
cables with conductive sheaths (usually copper braid), which are used in
applications where shielding of the centre conductors from the surrounding
electrical ambient is required. The interconnection of those shielded cables, not
covered by the present standard, is covered in ECSS-Q-ST-70-08.
This standard may be tailored for the specific characteristics and constrains of a
space project in conformance with ECSS-S-ST-00.

Normative references
The following normative documents contain provisions which, through
reference in this text, constitute provisions of this ECSS Standard. For dated
references, subsequent amendments to, or revision of any of these publications
do not apply, However, parties to agreements based on this ECSS Standard are
encouraged to investigate the possibility of applying the more recent editions of
the normative documents indicated below. For undated references, the latest
edition of the publication referred to applies.

EN reference Reference in text Title
EN 16601-00-01 ECSS-S-ST-00-01 ECSS system — Glossary of terms
EN 16602-10-09 ECSS-Q-ST-10-09 Space product assurance — Nonconformance control
system
EN 16602-20 ECSS-Q-ST-20 Space product assurance — Quality assurance
EN 16602-60 ECSS-Q-ST-60 Space product assurance — Electrical, electronic and
electromechanical (EEE) components
EN 16602-70-02 ECSS-Q-ST-70-02 Space product assurance — Thermal vacuum
outgassing test for the screening of space materials
EN 16602-70-08 ECSS-Q-ST-70-08 Space product assurance — Manual soldering of
high-reliability electrical connections
EN 16602-70-26 ECSS-Q-ST-70-26 Space product assurance — Crimping of
high-reliability electrical connections
EN 16602-70-28 ECSS-Q-ST-70-28 Space product assurance — Repair and modification
of printed circuit board assemblies
MIL-C-17G(3) SUP1 General specification for cables, radio frequency,
flexible and semi-rigid. (8 Jan 1996)

Terms, definitions and abbreviated terms
3.1 Terms from other standards
For the purpose of this Standard, the terms and definitions from ECSS-S-ST-00-01
apply, in particular for the following terms:
requirement
3.2 Terms specific to the present standard
3.2.1 minimum bend radius
inside radius of the bend measured on the outer surface of the cable
3.3 Abbreviated terms
For the purpose of this Standard, the abbreviated terms from ECSS-S-ST-00-01
and the following apply:
Abbreviation Meaning
fluorinated ethylene propylene
FEP
polytetrafluoroethylene
PTFE
sub miniature version A
SMA
voltage standing wave ratio
VSWR
Principles and prerequisites of reliable
soldered or crimped cable connections
4.1 Principles of reliable soldered or crimped semi-rigid
cable connections
Reliable soldered or crimped connections result from proper design, control of
tools, materials and work environments and careful workmanship.
The basic design concepts, adherence to which ensures reliable connections and
prevents joint failure, are:
a. Avoidance of dimensional mismatch between the coaxial-cable assembly
and the units being connected; i.e. not forcing the semi-rigid cable
assembly into position and thereby cracking or pre-stressing one of the
joints.
b. Use of cable-end connectors with retractable (non-captive) coupling nuts;
after completion of mounting, the coaxial-cable assembly is not in a state
of tension resulting from axial movement when the connectors are
threaded together.
c. Minimizing the internal stresses on the soldered or crimped connections
resulting from exposure to thermal cycling.
NOTE The thermal coefficient of expansion of the
dielectric is about ten (10) times that of copper and
in service this can introduce a tensile stress on the
joint.
d. The various assembly and mounting processes are covered by
quality-control inspection steps.
4.2 Prerequisites for assembly and mounting of
semi-rigid coaxial cables
Each supplier maintains documented soldering or crimping programmes which
meet the requirements of this Standard for the types of connections employed
and the articles involved. The programmes include procedures for training,
certification, maintenance of certified status, recertification and revocation of
certified status for soldering, crimping and inspection personnel. The supplier
also prepares and has readily available workmanship standards consisting of
satisfactory work samples or visual aids which clearly illustrate the quality
characteristics for all connections involved, including the applicable
illustrations in Annex B of this Standard.
Records are kept to provide identification between the finished product and the
operator. Records are also maintained of the training, testing and certification
status of assembly operators. Records are retained for at least one year, or
longer if this is a specific requirement of the customer’s project.
Equipment and tools are verified and calibrated periodically for proper
operation, and records of tool calibration and verification are maintained (see
clause 5.8).
For soldering or crimping requirements not covered in this Standard, the
supplier submits a process procedure including all pertinent quality
requirements to the customer’s relevant project office for approval in
accordance with ECSS-Q-ST-70.
4.3 Alternative coaxial cable technologies
Alternative coaxial cable technologies are accepted for application in individual
customer programmes following the completion of qualification and batch
acceptance test programmes in accordance with clause 5.7. The precise
test-programme and results are subject to review and acceptance by the
relevant customer programme. For materials used in the alternative technology
see ECSS-Q-ST-70-71.
Some mounting requirements for alternative technologies are given in clause
5.6.3 of this Standard.
Requirements
5.1 Preparatory conditions
5.1.1 Facility cleanliness
a. Unless classified as a cleanroom, the supplier shall maintain the areas in
which soldering is carried out in a neat orderly fashion with no loose
material that can cause contamination of the soldered connection.
NOTE Examples for loose material are dirt, dust, solder
particles, oils and clipped wires.
b. The supplier shall keep furniture to a minimum in the work areas and be
arranged to allow easy and thorough cleaning of the floor.
c. A washroom and eating, drinking and smoking facilities shall be located
close to, but outside, the soldering areas.
d. The supplier shall cover working surfaces with an easily cleaned hard
top or have a replaceable surface of clean, non-corrosive silicone-free
paper.
e. The supplier shall only use clean tools in the soldering operation.
f. The supplier shall remove excess lubricants from the tools before
soldering starts.
g. Before assembly, wire, terminal and connector contacts shall be visually
examined for cleanliness, absence of oil films and freedom from tarnish
or corrosion.
5.1.2 Environmental conditions
a. The supplier shall have an assembly area which has a controlled
environment that limits entry of contamination.
b. The supplier shall maintain the following environmental conditions in
the area:
1. Room temperature: (22 ± 3) °C
2. Relative humidity at room temperature (55 ± 10) %.
c. The work stations shall not be exposed to draughts.
d. The supplier shall use a filter system to supply fresh air to the room, so
that there is a positive pressure difference with respect to adjacent rooms.
5.1.3 Lighting requirements
a. The supplier shall ensure a lighting intensity of a minimum of 1 080 lux
on the work surface.
b. The supplier shall ensure that at least 90 % of the work area is
shadowless and without severe reflections.
5.1.4 Equipment and tools
5.1.4.1 Brushes
a. The supplier shall use brushes for cleaning, provided that they do not
scratch the metal surface to be cleaned or damage adjacent materials
beyond their visual inspection requirements.
NOTE Medium-stiff natural- or synthetic-bristle brushes
can be used.
b. The supplier shall clean these brushes before use in a solvent prescribed
in clause 5.2.3.
c. The supplier shall not use wire brushes.
5.1.4.2 Files
a. The supplier shall use smooth, single cut and mill type files for dressing
copper soldering-iron tips and removing burrs from the conductor.
b. The supplier shall not use files on surface-treated tips or pretinned items.
NOTE Nickel plated is an example for surface-treatment.
c. The supplier shall keep the files in a good condition and shall be cleaned
before use.
d. The supplier shall not keep the files in a cleanroom environment.
5.1.4.3 Cutting tools
a. The supplier shall use at least the following cutting tools for the
preparation of the semi-rigid cable:
1. jeweller’s saws having fine teeth;
NOTE A 0,28 mm - 0,33 mm blade is preferred.
2. single edged razor blades;
3. wire cutters.
b. The supplier shall use the jeweller’s saw together with a cable clamping
device.
NOTE An example of such a cable clamping device is
shown in Figure C-1.
c. The supplier shall cut the dielectric and inner conductor with a tool that
produces a clean, smooth-cut surface along the entire cutting edge.
d. The supplier shall not perform any twisting action during this cutting
operation.
5.1.4.4 Cable-forming tools
a. The supplier shall use bending jigs to form the cable to predetermined
shapes as identified by the engineering drawing.
NOTE An example of such a bending jig is shown in
Figure C-2.
b. The supplier shall use roller sizes consistent with each cable diameter.
c. The supplier shall use this equipment in such a way that it does not
introduce dents, nicks, wrinkles or cracks in the cable outer conductor.
5.1.4.5 Cable stripping and dressing tools
a. The supplier shall use cable stripping and dressing tools in such a way
that they do not twist, ring, nick, or score the underlying material
surface.
NOTE Many pieces of commercially available equipment
exist to strip the outer conductor or the dielectric
material. These can be automatic, power-driven
devices with precision factory-set non-adjustable
cutting and stripping dies, or precision hand-type
strippers with accurately machined cutting heads.
b. The supplier shall perform either periodic calibration or sample
evaluation during a production run.
5.1.4.6 Heat-treatment chamber
a. The supplier shall use thermal cycling cabinets, ovens, refrigeration units
or cold chambers capable of maintaining temperatures between -50 °C
and +90 °C
NOTE Under certain circumstances (see Table 5-2 step
3.3) greater temperature extremes can be required.
b. The supplier shall calibrate the working zone to within ±5 °C.
5.1.4.7 Soldering equipment
a. The supplier shall accomplish one of the following soldering methods
that conforms to the requirements on “Equipment and tools” of ECSS-Q-
ST-70-08:
1. by hand or
2. by using a resistance heating unit or
3. other contact heat source
b. When non-contact heat sources are utilized, the supplier shall set up,
operate and demonstrate to the satisfaction of the customer that the
particular method and schedule produces joints of an acceptable
standard.
NOTE This includes verification testing as detailed in
clause 5.7.
5.1.4.8 Crimping equipment
a. The supplier shall use the settings recommended by the tool
manufacturer as a guide.
NOTE This is necessary since manual crimping tools are
available; they are custom designed and applicable
only for particular connector shells.
b. The supplier shall set up the tool for the cable and connector types by a
detailed calibration programme based on the requirements of ECSS-Q-
ST-70-26.
c. The supplier shall perform verification testing as detailed in clause 5.7.
5.1.4.9 Assembly equipment, tools and processes for other
technologies
a. The supplier shall only use the equipment, tools, and processes for the
assembly of the cables and connectors that are designed to avoid damage
or degradation of the cables and connectors.
NOTE The equipment, tools, and processes can be subject
to a manufacturing audit by the customer before
application in their programme.
5.1.4.10 Defective or uncalibrated equipment or tools
a. The supplier shall promptly remove and replace defective or
uncalibrated equipment or tools from the work areas.
5.2 Material selection
5.2.1 Solder
a. The supplier shall use solder ribbon, wire and preforms, provided that
the alloy and flux conform to the requirements on “material selection” of
ECSS-Q-ST-70-08.
NOTE 1 The following solder alloys are approved:
• 60 Sn (remainder lead): For degolding
operations, coating and pretinning.
• 96 Sn (remainder silver): For making
coaxial-cable outer-conductor-to connector
solder joint.
• 96 Sn or 63 Sn (remainder lead): For
contact-pin soldering and cover soldering of
right angle connectors.
NOTE 2 Refer also to the table of “Chemical
composition of spacecraft solders” in ECSS-Q-
ST-70-08.
5.2.2 Flux
a. The supplier should perform degolding and pretinning operations with
activated fluxes.
NOTE Examples of activated fluxes are J-STD-004 Type
ROL1 and ROH1.
b. The supplier shall completely remove activated fluxes immediately after
use and before any further soldering operation.
c. The supplier shall only use pure rosin flux for spacecraft assembly work.
NOTE An example of pure rosin flux is J-STD-004 Type
ROL0.
5.2.3 Solvents
a. The supplier shall only use solvents for the removal of grease, oil, dirt,
flux and flux residues that are non-conductive and non-corrosive.
b. The supplier shall only use solvents for the removal of grease, oil, dirt,
flux and flux residues that do not dissolve or degrade the quality of parts
or materials or remove their identification markings.
c. The supplier shall label the solvents and maintain them in a clean and
uncontaminated condition.
d. The supplier shall not use solvents showing evidence of contamination or
decomposition.
e. The supplier shall not use solvents that transfer dissolved flux residue
onto contact surfaces.
NOTE This can be the case for switches, potentiometers or
connectors.
f. The supplier shall use solvents in conformance with ECSS-Q-ST-70-08,
clause 6.4h.
5.2.4 Cable selection
a. The supplier shall procure semi-rigid cables in conformance with the
detailed requirements of MIL-C-17G(3) SUP1.
NOTE The selection of a particular coaxial cable involves
consideration of the specific electrical, mechanical
and environmental requirements of the project.
b. The supplier shall procure semi-rigid cable with outer conductor
diameter standardized as either 0,085 inches or 0,141 inches (±0,001
inches) and fabricated from copper.
NOTE The outer conductor can be finished with silver
plating.
c. The supplier shall procure semi-rigid cable with dielectric material
composed of polytetrafluoroethylene (PTFE) or fluorinated ethylene
propylene (FEP).
d. The supplier shall select the material composition of the inner conductor
following a review of the specific project/equipment requirements.
NOTE 1 The review also considers the proposed
connector designs.
NOTE 2 In general copper is a suitable inner conductor.
5.2.5 Connector selection
a. The supplier shall only select approved connectors in conformance with
the requirements on “Quality levels” of ECSS-Q-ST-60, for use in
assembling solder-type semi-rigid cables.
b. The supplier may use connectors with the form of:
1. straight cable-end connector, with a centre contact, and
non-captive coupling nut;
NOTE See Figure C-3 for distinction between non-captive
and captive coupling nut connectors.
2. right angle cable-end connector.
3. flange-mount male receptacle, either two- or four-hole type.
c. The use of right angle cable-end connector shall be restricted to
applications where stress-free mounting of cables with these captive nut
connectors can be assured.
d. For other applications the use of right angle cable-end connector should
be minimized.
e. All non-metallic materials incorporated in the connector shall meet the
outgassing requirements according to ECSS-Q-ST-70-02.
f. The supplier shall not use pure tin or cadmium finishes.
g. For the use of special connectors for non-solder systems, the supplier
shall obtain customer approval.
5.3 Preparation of semi-rigid cable
5.3.1 General
a. The supplier shall ensure that the delivered coaxial cables are in the form
of straight lengths.
NOTE The initial preparation is similar for each cable
diameter and each connector type and whether
joining is by soldering or crimping.
5.3.2 Inspection of cable
a. The supplier shall remove the delivered cable from its container and shall
inspect it for dents, nicks, wrinkles, blisters and contamination.
b. If dents, nicks, wrinkles, blisters or contamination are identified, the
supplier shall reject the cable.
5.3.3 Cutting cable to initial oversize length
a. The supplier shall calculate the total specified length of the cable from the
engineering drawing.
NOTE This includes also bends and angles
b. The supplier shall then add approximately 10 mm to the length to allow
for bending, preconditioning and end dressing.
c. The supplier shall hold the cable in a special fixture and cut it to the
initial oversize length using the jeweller’s saw.
NOTE Such as fixture is illustrated in Figure C-1.
d. The supplier shall not overtighten the special fixture.
NOTE This is to avoid damage to the cable.
e. The supplier shall debur and examine the cut end.
5.3.4 Cable forming and minimum bend radius
a. All cables shall be formed to the required shape dimensions before cable
preconditioning using a bending jig.
NOTE An example of such a bending jig is shown in
Figure C-2.
b. The supplier shall perform only one bending operation to form each
shape.
c. The supplier shall not make attempts to reshape a bent cable.
d. The supplier shall establish design rules with minimum bend radii as
given in Table 5-1.
e. Each finished cable end shall have a minimum straight length of cable to
allow for clearance during the assembly and mounting operations.
f. The straight length shall be greater than 10 mm for 0,085 diameter cable.
g. The straight length shall be greater than 20 mm for 0,141 diameter cable.
h. The supplier shall prevent wrinkling or cracking when forming the cable.
i. The supplier shall apply a slow, even and continuous pressure when
bending of the cable.
Table 5-1: Design rules for minimum bend radius
Cable diameter (inches) Minimum bend radius (mm)
0,085 3,2
0,141 6,3
5.3.5 Preconditioning heat treatment
5.3.5.1 General
a. The supplier shall achieve core stress relief by preconditioning each cable
before it becomes a cable assembly.
NOTE The electrical and mechanical performances
specified for semi-rigid cables are achieved by a
compression fit between the outer conductor and
the dielectric core, which, in turn, necessitates
manufacturing processes that cause deformation of
the core by compression and elongation. The
resulting stress that is initially non-uniform tends
to equalize by cold flow within a few weeks after
the manufacturing and causes withdrawal of the
core into the cable. If this occurs in cable that has
become part of a cable assembly, the resulting
development of an air-gap at the cable/connector
interface causes an increase in the voltage standing
wave ratio (VSWR). Therefore the preconditioning
is performed.
5.3.5.2 Heat treatment process
a. The supplier shall perform preconditioning in conformance with Table
5-2 on cables that are formed into the required bend configuration.
b. The supplier shall not perform preconditioning on a soldered or crimped
cable.
NOTE This is valid even if only one lead end is
terminated to a connector.
c. The supplier shall place the entire cable in the thermal cycling
arrangement.
d. The rate of change of temperature shall not exceed 2 °C per minute.
NOTE Recommendations for dealing with special
requirements (e.g. higher operating temperature
extremes) can be obtained from cable
manufacturers.
Table 5-2: Preconditioning heat treatment process
Step Procedure
1 Cool the cable down to -45 °C and maintain this temperature for at
least 1 hour.
2 Let the cable return to room temperature and maintain it at this
temperature for at least 1 hour.
3.1 Heat the cable to the upper temperature and maintain it at this
temperature for at least 1 hour.
3.2 Ensure that the upper temperature at least +85 °C for both 0,085
inch diameter and 0,141 inch diameter cable.
3.3 When the equipment or spacecraft qualification temperatures
exceed these values, use the expected maximum operating
temperature as the upper preconditioning temperature.
4.1 Let the cable return to room temperature.
4.2 Trim off flush any protruding core with the edge of the outer
conductor.
5 Maintain the cable at room temperature for at least 1 hour.
6.1 Submit the cable to a minimum of three complete thermal cycles,
any dielectric protruding from the end of the cable being trimmed
off after each exposure.
6.2 If trimming of dielectric is necessary after the final cycle, perform
a further cycle until a trim-free cycle is achieved.
6.3 An alternative method is to accurately measure the protrusion
after each exposure.
6.4 When it is recorded that no additional protrusion has taken place,
perform the trimming operation at the end of that final thermal
cycle.
7 After the last thermal cycle, maintain the cable at room
temperature for at least 24 hours before further processing is
undertaken.
5.3.6 Trimming cable to final length
a. After the preconditioning, the supplier shall adjust the cable form to the
tolerance of the engineering drawing.
b. The supplier shall cut the cable to size such that when it is assembled it
fits with minimum stress.
c. The supplier shall perform cutting in conformance with the directions
given in clause 5.3.3.
5.3.7 Stripping the cable ends
a. The supplier shall use milling tools for stripping the cable ends.
NOTE See also clause 5.1.4.5.
b. For each stripping operation, the supplier shall follow written
instructions.
NOTE This allows a reproducible process that does not
damage the conductor surfaces.
c. The supplier shall regularly change cutting and milling blades.
d. The supplier shall remove burrs.
5.3.8 Inspection of stripped cable ends
a. For each of the stripped ends, the supplier shall perform a quality control
inspection checking the following criteria:
1. no metal or foreign particles are on the face of the dielectric.
2. the outer conductor contains no burrs or major surface defects and
is flush with the dielectric.
3. unremoved dielectric near the centre conductor does not exceed
0,2 mm.
b. The supplier shall specify the length of the wire inner conductor.
NOTE This is necessary since the length is dependent on
the connector type.
c. The supplier shall report measurements of the external length of the
centre conductor as shown in Figure 5-1 in the logbook for cable prior to
assembly with SMA connectors having separate pin contacts.
Remove burrs
Dielectric
Centre conductor
Outer conductor
0,2 mm max. unremoved dielectric is acceptable

Figure 5-1: Dimensional inspection requirements

5.4 Preparation for soldering assembly of semi-rigid
cables
5.4.1 General
a. The supplier shall establish written procedures which define the various
process steps including as a minimum the requirements of clause 5.4.2
and 5.4.3.
5.4.2 Degolding and pretinning
a. The supplier shall remove gold from all surface areas to be joined by
soldering.
NOTE The central contact pin can be degolded and
pretinned with a soldering iron by melting a short
length of 63 Sn or 60 Sn solder wire within the cup
to dissolve gold plating; the liquid solder can then
be wicked-out with stranded wire.
b. The supplier shall degold and pretin the jointing surface of the connector
body by fitting the connector to a suitable sized PTFE plug held vertically
in a vice.
c. The supplier may melt solder wire onto the jointing area and remove it
with the aid of a solder wick at least twice until the solidified pretinned
surface has a shiny appearance indicating a gold-free condition.
d. With the right-angle type of connector, the supplier shall degold and
pretin the solder mounting surfaces of the inspection and assembly cover
and the corresponding surfaces of the body before assembly.
e. The supplier shall pretin the cable’s outer and inner conductors.
f. The supplier shall check for possible dielectric protrusion after the cable
has cooled down to room temperature.
g. The supplier shall trim any protrusion with a scalpel blade.
h. The supplier shall check the fit of the pretinned cable in the connector.
i. The supplier may use activated fluxes for degolding and pretinning
operations.
j. If activated fluxes are used, the supplier shall remove them immediately
after the cable has returned to room temperature.
k. There shall be no dewetting of the solder on the cable conductor or on the
connector.
l. The supplier shall clean all surfaces with an approved solvent until they
are free from all residual flux and other visible contamination.
NOTE 1 For solvents refer to clause 5.2.3.
NOTE 2 The recommended degolding and pretinning
temperatures are 250 °C to 280 °C, and 210 °C
to 260 °C, respectively, when using solder
immersion.
m. The supplier should perform pretinning just before proceeding with the
assembly of the connector on the cable.
5.4.3 Solder preforms
a. The supplier shall either
 use solder preforms with an internal diameter matching the outer
diameter of the coaxial cable which are available as prefluxed
continuous rings, or
 prepare solder preforms by winding 96 Sn solder wire around
mandrels having the same outer diameter as the coaxial cable
(0,085 or 0,141 inches).
b. The supplier shall predetermine the diameter of the wire and the number
of turns by trials.
NOTE This is necessary since they depend on the type of
connector.
c. The supplier shall make as many preforms as the number of connectors
to be soldered.
d. The supplier shall use a scalpel blade to cut solder turns in a direction
perpendicular to the wire wrap.
NOTE This is shown in Figure C-4.
e. Before use, the supplier shall clean the preforms with one of the solvent
cleaners specified in clause 5.2.3
5.5 Assembly of
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