This invention employs a generic axial modulating mechanism to manipulate the pitch of the blades of a fan or propeller; conceptually, this is a threaded bolt and nut where the threaded bolt would be analogous to a rotating shaft, with an acme thread (i.e. the “rotor thread”) on its exterior, and the nut would be analogous to the axial modulator of this teaching. The “nut,” or axial modulator, is further spun above and beyond the rotation in the rotating bolt or rotating shaft. The axial motion of the axial modulator is then deployed to do useful work i.e. manipulate the pitch of the blades of a fan or propeller. This invention is a continuation in part of a previous variant disclosed where the means of modulating the axial modulator was magnetic. The variation introduced in this teaching instead achieves the modulation using a gear-driven arrangement.