On Thu, 18 Feb 2016 20:47:28 -0800 Chris Albertson <albertson.ch...@gmail.com> wrote:
> On Thu, Feb 18, 2016 at 11:23 AM, Nicklas Karlsson > <nicklas.karlsso...@gmail.com> wrote: > > > I guess it would be possible to position an ordinary disc read head quite > > accurate. Either one for DVD/CD or magnetic. How many bits are stored per > > turn? > > > > Those devices use the data that is recorded on the spinning platter to > determine where the read head is. The head is then served to follow > the track. It works well enough that is the spindle bearing is loose > the head can follow the track as it wobbles > > The CD/DVD track is a long spiral (alike on a vinyl record) so the > head must continually move if it is to read. All of these are not > very good at absolute positioning They would be good at absolute positioning if a suitable pattern is added. It should also be possible to figure which bit is at position right now. At standstill I guess there would be a need for moving disc head. How good could it be? There have been extensive research on packing bits as tight as possible ==> how many bits are there per turn? Then in practice it is a matter of what could be bought. Nicklas Karlsson ------------------------------------------------------------------------------ Site24x7 APM Insight: Get Deep Visibility into Application Performance APM + Mobile APM + RUM: Monitor 3 App instances at just $35/Month Monitor end-to-end web transactions and take corrective actions now Troubleshoot faster and improve end-user experience. Signup Now! http://pubads.g.doubleclick.net/gampad/clk?id=272487151&iu=/4140 _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
