Abstract: A tuning index tool for use in determining the degree of tuning necessary for a tunable optical fiber connector has a first stationary member having a connector adapter affixed thereto and a second movable member within the first member and spring loaded with respect thereto. The second member has a connector adapter affixed thereto axially aligned with the adapter in the first member. The movable member is incrementally rotatable with respect to the stationary member by being pulled against the spring force to disengage the ferrules of connectors in the adapters, which are aligned in a split sleeve. Rotation changes the orientation of the eccentricity vectors of the two connectors, and hence the insertion loss. Measurements of insertion loss are made, and the orientation of the connectors for minimum loss is noted.

Abstract: An optical fiber connector that is tunable despite being fully assembled has a assembly having an enlarged ferrule holding member or flange that has a multi-faceted periphery, preferably in the shape of a hexagon. The connector has a front housing portion that has a multi-faceted seating region for the flange. The flange is disengageable from the seating region for tuning rotation by being movable axially toward the rear of the housing against the force of a spring. The connector can be tuned by incremental rotations of the assembly when the flange is disengaged.

Abstract: A tuning wrench for tuning optical fiber connectors has an enlarged portion from which extends a limiting portion having a diameter greater than the diameter of the opening in the ferrule housing portion of an optical connector. A tubular member protrudes from the limiting portion and has an internal diameter dimensioned to slide over the connector ferrule. The distal end of the tubular member has a pair of tangs adapted to fit within or openings in the front of the flange portion of the ferrule-barrel member of the connector. The distance from the face of the limiting member to the tangs is such that axial pressure on the wrench moves the flange rearwardly out of engagement with its housing but the face of the limiting member butts against the front of the housing before the spring member within the housing bottoms. Rotation of the wrench thus causes rotation of the ferrule-barrel assembly to alter the angular orientation of the eccentricity vector of the ferrule.