Abstract: A D.C. multi-phase brushless motor having M phase stator windings and an N pole rotor, with M and N being integers, a sensor for sensing rotor position and providing rotor position signals to a motor controller is disclosed. The sensor comprises a circular permanent magnet, mounted externally to a motor at one end of a rotor with the magnet having N poles, and M sets of paired Hall effect devices, mounted adjacent the magnet, wherein each of the M sets of paired Hall effect devices are mounted in adjustable relationship to the magnet with respect to radial and angular distance. The sensor is mounted within a housing mounted externally to an end of a motor adjacent the rotor end having the magnet mounted thereon with the M sets of paired Hall effect devices mounted within and upon the housing in adjustable relationship with the magnet.