> -----Original Message----- > From: tclug-list-bounces at mn-linux.org > [mailto:tclug-list-bounces at mn-linux.org]On Behalf Of Robert > Sent: Friday, October 01, 2010 2:42 PM > To: tclug-list at mn-linux.org > Subject: Re: [tclug-list] Hidden hard drive partitions > > > It seems Chuck finds this topic very interesting and productive after > all! Sorry: neither. > I would like to learn more. So, can you show some documentation Chuck? > Something current that will give me more information than is practical > in this venue? Read up on Guzik spin stands (and others) and what their instrumentation does for head and platter research. Follow the references cited. Look for mentions of various spin stands as keywords to get other data. Guzik is a pretty unique key word. Until you have a pretty good grasp of PRML (and similar) capabilities, the info about data and data recovery won't make much sense. http://www.guzik.com/ PRML = Partial Response Maximum Likelihood http://en.wikipedia.org/wiki/Partial_Response_Maximum_Likelihood This PRML reference is at best a tip of an iceberg. A real PRML data recovery does coherent integration of the analog waveform so noise is suppressed (integrl of noise is zero) and data bit energy is enhanced integral of a "one" increases linearly over the bit's period.. more complicated, because it's a biphase coding). Would not look like signal peak values as if the same detector as in this simple description. Chuck