The user can select the speed of 1x,2x,3x,4x,5x,6x easily from the operation board. And there is a correction function in the program of the drive circuit which makes the tolerance to reach an accuracy of +0.005% or -0.005%(sidereal time). It can automatically track the moving direction of astronomical objects and fully simulate the effects of the earth's rotation. A North-South switch permits drive operation anywhere in the world.