Re: Buying Apple Floppys

[eeastman@apple2.com]

Sorry, Jeff.  I inadvertantly sent this to sender instead of the group.

TPI is consistent for 5.25" disks as it is for 3.5" disks.  The TPI will
not tell you how dense the media is though.  The drives of the era were
limitied by the physical allignment of the drive head.  The density is
what determines the magnetic properties and whether or not the drive can
write to it successfully.

All my disks are 96 TPI (Tracks per inch), but they are double density
media.

Also worth mentioning is that the Apple II drive can stop precisely on
72 of the tracks, physical limitations in the drive make it not possible
to use every track.  According to 'Beneath Apple DOS' Head width
prevents using every track, it's just too wide to not read data from
adjoining tracks so Apple drives (DOS) are forced to use every other
track.  The guide that the head travels along is not long enough to
access the rest of the tracks able to be used by other drives.

Thankx,
Ed

Rubywand wrote:
> 

>      96 TPI sounds high for 5.25" DD. Like, the standard Apple II 5.25"
> diskette is 35 tracks.