11 Apr
2007
11 Apr
'07
1:35 a.m.
Regarding Als idea of reading the disk backward - It
would be a fairly
simply matter to make up a version of ImageDisk which reads from the
inside out.
Why would reading from inside to outside (track 80 to
track 0) help?
I have observed there is a higher rate of failure reading inside tracks.
If there is binder shed, it may help to start on the tracks that are more
difficult to read first (before the head starts to clog).
The bit about non-sequential track reading comes
mostly from trying to recover partially crashed 2315 media. You don't want
the ceramic of the flying head within 1/2" of the bad spot for very
long, or it will clog up and crash.
By moving the head on the floppy you knock the accumulating crud across
the surface of the disc as you seek, rather than having it pile up on the
leading edge of the head. Not great, but carving grooves in the floppy is
worse.