Mechanical Specifications; Precision 7Mm Connectors - Agilent Technologies 346A Operating And Service Manual

Caring for Connectors

Mechanical Specifications

Mechanical Specifications
The critical dimension to be measured, regardless of connector type, is
the position (generally, the recession or setback) of the center conductor
relative to the outer conductor mating plane.
Mechanical specifications for connectors specify a maximum distance
and a minimum distance that the center conductor can be positioned
behind (or, in female Type-N connectors, in front of) the outer conductor
mating plane. Nominal specifications for each connector type exist, but
the allowable tolerances (and sometimes the dimensions themselves)
differ from manufacturer to manufacturer and from device to device.
Therefore, before gaging any connector, consult the mechanical
specifications provided with the connector or the device itself.

Precision 7mm Connectors

In precision 7mm connectors, contact between the center conductors is
made by spring-loaded contacts called collets. These protrude slightly in
front of the outer conductor mating plane when the connectors are apart.
When the connection is tightened, the collets are compressed into the
same plane as the outer conductors.
For this reason, two mechanical specifications are generally given for
precision 7mm connectors: the maximum recession of the center
conductor behind the outer conductor mating plane with the center
conductor collet removed; and a minimum and maximum allowable
protrusion of the center conductor collet in front of the outer conductor
mating plane with the collet in place.
The center conductor collet should also spring back immediately when
pressed with a blunt plastic rod or with the rounded plastic handle of the
collet removing tool. Never use a pencil or your finger for this purpose.
With the center conductor collet removed, no protrusion of the center
conductor in front of the outer conductor mating plane is allowable, and
sometimes a minimum recession is required. Consult the mechanical
specifications provided with the connector or the device itself.
62 Appendix A