The ornamental design for a broadcastingcontrolunit, as shown and described.
FIG. 1 is a perspective view of the broadcasting control unit.
FIG. 2 is a front elevation view thereof.
FIG. 3 is a rear elevation view thereof.
FIG. 4 is a right side elevation view thereof.
FIG. 5 is a left side elevation view thereof; and,
FIG. 6 is a top plan view thereof.
The broken lines in the drawings depict subject matter that is hereby disclaimed and forms no part of the claimed design. The bottom view of the broadcasting control unit illustrated in FIGS. 1-6 forms no part of the claimed design.