What this BNC plug is for
The Hirose BNC-P-1.5W(40) is a BNC plug, male pin, designed for 50 Ohm systems and rated to 2 GHz. It terminates 1.5D-2W cable with a solder center contact and a clamp shield termination — a clean, field-reliable joint when the prep is right. The bayonet lock gives a quarter-turn mate that holds under light vibration, and the silver-plated brass center contact and nickel-plated brass body handle 1000 mating cycles without signal degradation. The PTFE dielectric keeps the impedance steady through the joint.
What cable does it fit?
This plug is built for cable group 1.5D-2W — a thin, flexible 50 Ohm coax, roughly 1.5 mm diameter, common in internal RF jumpers and test leads. Match the body to the reel: the clamp shield termination and solder center pin are sized for that specific cable OD and dielectric. Using a different cable group (like RG-174 or RG-316) will change the impedance through the connector and may not seat the ferrule properly.
Free-hanging (in-line) mount, male pin, mates with any standard BNC jack (female) of the same 50 Ohm impedance. The bayonet lock engages with a quarter turn — no threads, no torque spec. Solder the center conductor to the pin, clamp the braid under the shield ferrule. The silver plating on the center contact gives good solder wetting and holds up to repeated mating cycles.