Rotating memory data recovery

From: Paul Koning <pkoning_at_equallogic.com>
Date: Mon Sep 13 10:44:56 2004

>>>>> "John" == John Lawson <jpl15_at_panix.com> writes:

 John> On Sat, 11 Sep 2004, Tom Jennings wrote:

>> On Sat, 2004-09-11 at 14:42, John Lawson wrote:
>>>
>> I was assuming PC audio cards would not be fast enough. I am an
>> analog person too, but not to your extent of expertise.

 John> What can the actual drum clock be... I dunno... another
 John> reason to slow the drum; see below further...

No, don't do that. The heads might not fly if you do that, and you'd
end up with an instant head crash on every head.

Digitizing at 8 bits, more if you can get it easily, and minimally 8x
the data clock rate sounds like the way to go. That's clearly more
than the original used. The argument for doing so is that it will
give you a way to recover data that would not be recoverable with the
original electronics.

Evaluation boards from A/D chip makers may be a good cheap way to get
this. Alternatively, low end digital oscilloscope cards. There's a
company named GaGe that's in that business, but I don't know their
prices (or anything else about them); there are bound to be plenty
more.

        paul
Received on Mon Sep 13 2004 - 10:44:56 BST