RP-SMA adapter for 50-ohm microwave paths through 18 GHz
The Hirose SMA(R)-A-JJ is a straight, in-line RP-SMA jack to jack adapter — two female-threaded interfaces, each with a male center pin. It converts one RP-SMA connection to another in the same series, so it is useful for extending a cable run, reversing gender on a bulkhead, or linking two RP-SMA-terminated components without an extra cable. The reverse-polarity (RP) designation means the center conductor gender is swapped relative to standard SMA: the jack body has a male pin, not a female socket. The passivated stainless steel body and gold finish resist corrosion in lab, field, or production test environments.
What the 18 GHz and 1000-cycle ratings mean for your link
The 18 GHz maximum frequency is the adapter's usable ceiling — above that, the interface geometry starts to support higher-order modes and the VSWR degrades. For a 6 GHz Wi-Fi backhaul or a 10 GHz satellite IF chain, this adapter has headroom; at 24 GHz it is out of spec. The 1000 mating cycle rating comes from the gold-over-beryllium copper center contacts, which resist the fretting and wear that tin or brass contacts would show after a few hundred thread engagements. That cycle life suits it for test equipment where the adapter is swapped between DUTs daily, or for field-deployed links that see occasional reconnections. The threaded coupling ensures the pair stays mated under vibration — no snap-on retention here.