20 Oct
2012
20 Oct
'12
12:01 p.m.
On 10/20/2012 11:35 AM, Paul Anderson wrote:
Since the data is stored magnetically, I don't
believe there's a microscope technology that could do it.
--------
Paul Anderson -- VE3HOP
On 2012-10-20, at 1:22 PM, Chris Tofu <rampaginggreenhulk at yahoo.com> wrote:
> I've been meaning to ask this. If you have a disk that can't be read in a
drive, is it possible to extract data using optical methods, i.e a microscope? How
powerful would the unit need to be?
There was a material called Magna-see which
would deposit very small
particles on a magnet recording. It is mostly useful to alignment of
tape drive paths and optical inspection of the results of recordings there.
We used some on a 2311 (I think) platter from Microdata Marathon. The
drive was 2.5mb on 2 surfaces, or 1.2 on one. You could see the tracks
and some variation, and sectors, but probably not well enough to extract
data.
I've never used my Magnasee on a modern platter, but one needs to
remember that the recording on the drives I mention above was
longitudinal to the head path on the media, and now the recording is
vertical. I don't know with Magnasee if you would see any difference
between a 0 and a 1 with vertical recording. Regardless of the magnet
state, the same amount of Magnasee material would likely stick to a 0 or
1 cell.
The other sport would be looking at a recording developed by Magnasee,
and recall that there are encoding issues like NRZ, NRZI involved. Not
for the faint hearted to do with a microscope and a notepad.