Abstract: The slats of a venetian blind panel are divided into upper and lower sections, the tilt of the panel slats being separately adjusted for each section, utilizing a three-position switch attached to a rotatable and horizontally movable control rod. Depending upon the position of the switch, the control rod adjusts the tilt of the slats in the upper section only, the lower section only, or both sections together. The mechanism includes at least two spline gears which can adjust the tilt of the slats of the upper and lower panel sections when the control rod is rotated. The control rod is horizontally movable and mounts inner spline gears and engaging outer spline gears. In one position, the inner spline gear engages a first outer spline gear, and upon rotation, will adjust the tilt of the upper blind section.