The ornamental design for a jackconnector, as shown and described.
FIG. 1 is a front, top and right side perspective view of a jack connector showing our new design;
FIG. 2 is a front elevational view thereof;
FIG. 3 is a rear elevational view thereof;
FIG. 4 is a left side elevational view thereof;
FIG. 5 is a right side elevational view thereof;
FIG. 6 is a top plan view thereof; and,
FIG. 7 is a bottom plan view thereof.
The broken line showing unclaimed subject matter of the internal elements of the connector is for illustrative purposes only and forms no part of the claimed design.