[cctalk] Re: Running DOS executables on other versions of DOSRe: Looking for Sharp PC-5000 disk drive (CE-510F or possibly MZ-80B)

Diskettes: For writing 10K/180K/320K/360K disks, use THOSE, never 1.2M dikettes! "360K" diskettes are 300 Oersted; 1.2M are 600 Oersted. The 1.2M/600-Oersted dikettes use a reduced write current (pin6? of the interface) Twiggy disks, and Amlyn cartridge (5 disks in a jukebox holder) were 600 Oersted. If you try to use 1.2M diskettes for the lower density, it might seem to be working, but the recording doesn't last. Using Roytype (who the college purchasing agent was sleeping with) HD disks with TRS80 gave us disks that didn't keep their contents long enough to sneakernet to another machine! To tell them apart, there is usually a difference of color. and 1.2M diskettes generally do NOT have a hub reinforcing ring (unless somebody manually added one later) 360K diskettes generally come with a hub reinforcing ring. (except for EARLY ones, such as Verbatim before they came out with "Datalife") The reinforcing ring was because many early drives would occasionally misclamp and mangle the edges of the hole; later drives, including all 1.2M were probably an improved shape of clamping cone. In contrast, 720K/400K/800K 3.5 inch disks are 600 Oersted; 1.4M 3.5" disks are about 750 Oersted Which is close enough that a high quality 720K disk could be used as a low quality 1.4M, . . . -- Grumpy Ol' Fred cisin(a)xenosoft.com