75-Ohm Mini BNC for Video and Broadcast – What the 4 GHz Ceiling Means
The 4 GHz frequency ceiling is the hard limit for usable signal — above that the insertion loss and return loss climb, so keep the signal below that line. The gold-plated center contact on a brass pin handles the 500 mating cycles typical for field-installed coax, not a daily test-port. The 0.1 dB insertion loss is low enough that a single connector in a video run won't shift the signal level noticeably.
Cable Compatibility and Kit Contents
This plug is a 3-piece kit — connector body, crimp contact, and ferrule — so one order line covers the termination hardware. The cable group covers RG-122, 180, 180A, 180B, 195, and Belden 1855, 1865A. The shield is crimped, the center contact is crimped, so you need a hex crimp die set sized for the cable OD and the ferrule.
The 31-70260 is the 75-Ohm member in the Amphenol RF BNC Mini family. The 31-315-RFX and 31-320-RFX are 50-Ohm plugs — same bayonet lock, same 4 GHz max, same 500 mating cycles. The 31-70260 uses a PTFE dielectric while the 50-Ohm parts use polyoxymethylene (POM) acetal. The 75-Ohm version is for video/broadcast; the 50-Ohm versions are for data/telecom. The 31-70260 is the standard 75-Ohm mini BNC for RG-type cables.