10 Mar
2005
10 Mar
'05
5:28 p.m.
One other issue that can cause trouble with the "higher" track numbers is
write precompensation. As the track number gets higher you move closer to
the center of the disk and the bit density increases. Write precompensation
makes adjustments to the write data to compensate for the changes in bit
density. This would only be a problem though if you are using double density
(MFM).
Good luck, Steven C.
Ok, I finally found an 8" drive that worked. I don't think there's a
coincidence that it's half-height, and seems to have been made in the 1982
timeframe. I can't tell who the manufacturer is because I haven't
unbolted it from the chassis it's installed in to check yet.
I was able to format a disk mostly successfully (more on this in a bit)
and transfer MS-DOS 6.22 to it. It was pretty nifty booting DOS on my PC
off an 8" drive ;)
So anyway, when I was formatting the disk, it didn't seem to like the last
4-6 tracks or so. Above the clatter of the noisy fan (bad bearings) I
could hear the head recalibrating. When the format finished, it reported
107520 bytes in bad sectors. This comes out to 210 bad sectors (assuming
512 bytes per sector) which comes out to some weird number of tracks.
Aren't there supposed to be 26 sectors per track?
The main hurdle has been jumped, so I'm in good shape at this point.
Thanks for the tips, all!