In article .net,
Alexander Grigoriev wrote:
Considering that the track pitch in modern drives is about 100 nm (and bit
length half of that), it's a miracle that they work at all!

"Arno Wagner" wrote in message
...

Are you saying this recovery is now limited to electron microscopy level
only ?

I am saying that the harddrives are close to the s/n ratio of the
surface coating. There is just not enough space to squeeze two signals
into the place of one. The "imprecise positioning" will likely get
overwritten when the neighbouring tracks are written. In addition the
head-positioning has gotten extremely accurate for writes and tracks
have gotten very slim and close together. This is not floppy
technology anymore. It is quite possible that the original signal is
just not there anymore (i.e. vanished in the bachground noise) after a
single overwrite and _nothing_ can recover it.

Arno
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IMO the non-classified articles that described use of electron
microscope techniques are now several years old and disk capacities
have gone from the maybe 2GB to 200GB over that time. It's safe to
assume that the issues assiciated with forensic data recovery have
changed, and it's probably harder, much harder.

IBM developed much if the head and surface technology that made our
disks possible. A google for "disk proximal recording" will get you
some information.

I have no access to any seecrreet information.

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