On Mon, 3 May 2010 12:58:05 -0600 YES NOPE9 wrote: > Thanks John for pointing out that is requires registering. > I will change that. > Gus > Hi Gus, I guess you'll have found most of what you needed from the internet. The XY movement you describe is probably Tilt/Z movement - the head tilts perpendicarly to the tracks, to follow them, and the Z movement is to focus. Some systems use three sensors, one to read, and two to produce the alignment info necessary. John -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist