TE 502750-1 OPTIMATE ST Simplex Singlemode Coupler
The TE Connectivity 502750-1 is an OPTIMATE series ST-to-ST simplex coupler built for singlemode fiber. It joins two ST-terminated simplex patch cables or pigtails in a panel-mount bulkhead feedthrough — the ceramic ferrule alignment sleeve keeps insertion loss low by centering the fiber cores within the 9/125 µm singlemode tolerance. A dust cap ships with the coupler to protect the sleeve when the port is unmated.
There is no official direct-replacement order code on record from the manufacturer. If your design can accept a parametric equivalent, the replacement search should start with a current-production ST simplex singlemode coupler from the same OPTIMATE family; confirm the panel cutout and ferrule alignment match your application.
Singlemode means the alignment sleeve is precision-bored for 9/125 µm fiber — using this coupler on a multimode (50/125 or 62.5/125) link will work optically but adds unnecessary cost. Simplex means one fiber passes through; if your link is duplex (two fibers, one transmit one receive), you need two of these couplers or a duplex adapter. The ST interface uses a bayonet-style twist-lock — common in telco and CATV plant, field-terminated with ST connectors. Panel-mount bulkhead requires a round cutout and a hex nut to secure the coupler to the enclosure wall. The -20°C to 75°C operating range covers indoor telecom closets and outdoor cabinets in temperate climates; derate the housing if the coupler sits near heat sources inside a sealed enclosure.