We claim the ornamental design for a cordless telephone base station, as shown and described.
FIG. 1 is a top perspective view of a cordless telephone base station of the present invention;
FIG. 2 is a front view thereof;
FIG. 3 is a top view thereof;
FIG. 4 is a bottom view thereof;
FIG. 5 is a first side view thereof;
FIG. 6 is a second side view thereof; and,
FIG. 7 is a rear view thereof.
A recess in the front left corner is a holder for holding a handset upright.
The ornamental design which is claimed is shown in solid lines in the drawings. Any broken lines in the drawings are for illustrative purposes only and form no part of the claimed design.