29 May
2005
29 May
'05
9:14 a.m.
Lee wrote:
If someone only had a 48 tpi drive and
couldn't read the disk written on the 96 tpi drive the usual solution
was to format it on the 48 tpi drive and then re-write it on the 96
tpi drive.
That's exactly what *DOESN'T* work well.
The 48 TPI drive writes a nice wide track. The 96 TPI drive can
only overwrite a narrow strip down the middle of that wide track.
The result is a track that can be read back consistently on the 96 TPI
drive, but not on the 48 TPI drive. Because of the wider head gap,
the 48 TPI drive will get a mish-mash of the old 48 TPI data (in this
case, "empty" sectors from the format process) and the new 96 TPI data.
The only way to do this reliably is to take disks that have NEVER been
formatted for 48 TPI (even at the factory), or that have been bulk-
erased, then write 48-TPI data on the 96-TPI drive.
Eric