IEC 63138-2:2023

IEC 63138-2 ®
Edition 2.0 2023-10
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Multi-channel radio-frequency connectors –
Part 2: Sectional specification for MQ4 series circular connectors

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IEC 63138-2 ®
Edition 2.0 2023-10
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Multi-channel radio-frequency connectors –
Part 2: Sectional specification for MQ4 series circular connectors
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 33.120.30 ISBN 978-2-8322-7710-2

– 2 – IEC 63138-2:2023 RLV © IEC 2023
CONTENTS
FOREWORD . 4
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 7
4 Mating face and gauge information . 8
4.1 Mating face dimensions . 8
4.1.1 MQ4 socket connector . 8
4.1.2 MQ4 plug connector . 10
4.1.3 Mating face of RF channel . 14
4.2 Gauges . 17
4.2.1 Gauge for RF channel. 17
4.2.2 Gauge rings for plug outer contact . 19
4.2.3 Gauge for MQ4 socket connector . 20
4.2.4 Gauge for MQ4 plug connector . 21
5 Quality assessment procedure . 23
5.1 General . 23
5.2 Rating and characteristics . 23
5.3 Quality assessment . 25
5.3.1 General . 25
5.3.2 Inspection procedure . 25
5.3.3 Lot-by-lot inspection . 27
5.3.4 Periodic inspections . 28
6 Instructions for preparation of detail specifications . 30
6.1 General . 30
6.2 Identification of the detail specification . 30
6.3 Identification of the component . 30
6.4 Performance . 30
6.5 Marking, ordering information and related matters . 31
6.6 Selection of tests, test conditions and severities . 31
6.7 Blank detail specification pro forma for MQ4 series circular connectors . 31
7 Marking . 36
7.1 Marking of components . 36
7.2 Marking and contents of package . 36

Figure 1 – MQ4 socket connector . 9
Figure 2 – MQ4 quick-lock plug connector . 11
Figure 3 – MQ4 threaded plug connector . 13
Figure 4 – Mating face of RF channel . 16
Figure 5 – Gauge for socket contact of RF channel . 18
Figure 6 – Gauge for plug outer contact . 19
Figure 7 – Gauge for MQ4 socket connector . 20
Figure 8 – Gauge for MQ4 plug connector . 22

Table 1 – Dimensions of MQ4 socket connector . 10
Table 2 – Dimensions of MQ4 quick-lock plug connector . 12

Table 3 – Dimensions of MQ4 threaded plug connector . 14
Table 4 – Dimensions of RF channel . 17
Table 5 – Dimensions of gauge for socket contact . 18
Table 6 – Dimensions of gauge for plug outer contact . 19
Table 7 – Dimensions of gauge for MQ4 socket connector . 21
Table 8 – Dimensions of gauge for MQ4 plug connector . 23
Table 9 – Rating and characteristics . 24
Table 10 – Qualification inspection . 26
Table 11 – Lot-by-lot inspection . 28
Table 12 – Sampling plans for mechanical compatibility and return loss inspection . 28
Table 13 – Periodic inspection . 29

– 4 – IEC 63138-2:2023 RLV © IEC 2023
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
MULTI-CHANNEL RADIO-FREQUENCY CONNECTORS –

Part 2: Sectional specification for MQ4 series circular connectors

FOREWORD
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This redline version of the official IEC Standard allows the user to identify the changes
made to the previous edition IEC 63138-2:2020. A vertical bar appears in the margin
wherever a change has been made. Additions are in green text, deletions are in
strikethrough red text.
IEC 63138-2 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 second edition cancels and replaces the first edition published in 2020. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) change the supplementary key and groove position degree from 0,1 to 0,05 in Figure 1,
Figure 2, Figure 3, Figure 7 and Figure 8;
b) change dimension q from min.1,60 to min.1,65 in Table 1;
c) add an electrical reference plane in Figure 4;
d) add dimensions in Table 1;
e) change dimension n from max.1,55 to max.1,50 in Table 2, Ta
...