How common are 16-sector hard sectored disks?
Not very common.
I found some disks for my AES 7100, and that's what they are (17
holes!).
Yep, index plus 16 sector holes. The 17th one is oddly positioned to the
rest so the system can tell it's at the start/end of the media.
Oh, 10 sector (NS*) have 11 holes (if you want to be picky 12... theres
that big one dead center<grin>).
Unfortunately, the only Software disk I found only
boots part way. The
other disks are Data disks, and they give me an error when I try to boot
from them. <s>
No idea on the system used, likely unique to them.
Allison