We claim the ornamental design of a radio remote control unit, as shown and described.
FIG. 1 is a referential perspective view of a radio remote control unit when the wheel unit is placed on the back side according to a first configuration;
FIG. 2 is a perspective view of the radio remote control unit of FIG. 1 when viewed from the front and left side top when the wheel unit is placed on the front side according to a second configuration which is subsequently illustrated in FIGS. 3-9;
FIG. 3 is a perspective view of the radio remote control unit when viewed from the back and right side top;
FIG. 4 is a front view of the radio remote control unit;
FIG. 5 is a back view of the radio remote control unit;
FIG. 6 is a top view of the radio remote control unit;
FIG. 7 is a bottom view of the radio remote control unit;
FIG. 8 is a right-side view of the radio remote control unit;
FIG. 9 is a left-side view of the radio remote control unit; and,
FIG. 10 is a perspective view of the radio remote control unit in the second configuration with the antenna on the right side having been moved to a standing up or vertical position from a horizontal position.