SMPM Jack for Millimeter-Wave Signal Paths
The Amphenol 925-201J-51S is an SMPM jack with a male pin, built for DC-to-40 GHz signal paths where the standard SMP interface is too bulky. The 50 Ohm controlled impedance matches the system trace impedance — any mismatch at this frequency band shows up as a reflection that degrades the link budget. The stainless steel body gives it a corrosion-resistant shell that holds up in outdoor or lab environments, and the extended insulation feature increases the creepage distance between the centre conductor and the shell, which matters when the system runs at higher altitudes or in condensing humidity. The smooth bore feature means the mating interface has no detent ramp — insertion force is lower than a full-detent SMPM, making it suited for blind-mate panel-to-module connections where the connector pair is aligned by the chassis hardware, not by the connector itself. The snap-on fastening locks the pair once fully seated; you feel the click when the outer ring engages.
Mounting and Termination on the Panel
The shield termination is solder: you solder the braid or a ground lug to the body. The centre contact also terminates with solder — a cup or a through-hole pad that accepts the centre conductor of the coax cable. Beryllium copper is a standard choice for RF contacts that need to maintain consistent normal force after repeated mates.