QMA Bulkhead Receptacle — 50 Ohm, DC to 6 GHz
The 1408340-1: The QMA interface uses a snap-on fastening mechanism that provides quick, push-to-engage mating while maintaining the RF performance of a threaded SMA — a common choice where panel space is tight and the installer needs one-hand blind-mate capability. This single-port version is rated DC to 6 GHz with a maximum insertion loss of 0.25 dB, covering most cellular bands, GPS /L2, ISM, and Wi-Fi up to 6 GHz. Extended insulation on the PTFE sleeve adds creepage distance for the 335 V rating, reducing the risk of flashover in humid or high-altitude environments.
The shield termination is solder — the installer solders the cable braid or a grounding strap to the body after the nut is tightened. The center contact termination is also solder, so the cable centre conductor is soldered directly into the socket contact. There is no crimp step; the assembly requires a soldering iron and a torque wrench for the nut.
That is a modest figure — adequate for a panel port that gets connected a few times during installation and occasional service, but not designed for daily disconnect/reconnect in a test lab or portable equipment. The gold-plated beryllium copper centre contact resists corrosion and maintains contact resistance across those cycles, but the snap-on coupling mechanism itself will wear with repeated engagement. For a port that sees frequent reconnection, consider a threaded SMA variant with a higher cycle rating.