[cctalk] Re: Need a 1.2mb 5.25 floppy

For my students, I used analogies and visual aids. 1/48, 1/96 is a little hard for some to visualize. "48 tracks per inch, is about half a millimeter spacing, with the actual data being aabout a third of a millimeter wide. 96 tracks per inch is about a quarter of a millimeter spacing, with the cata being about a sixth of a millimeter wide" "If you make stripes with a 2 inch wide paint brush, . . . you can also make stripes with the same spacing, with aa 1 inch wide paint brush, . . . BUT, with a single stroke, can you paint over a 2 inch stripe with a 1 inch brush? No, you'd have to clean all of the old paint off first, or start with a virgin canvas." "car tires make two tracks. Motorcycles could make tracks the same spacing. But, motorcycles won't obliterate the car tire tracks." I took a wide piece of colored chalk and made a series of stripes. I held up a piece of cardboard (file folder) with a slit in it, and looked at one stripe. With a narrower piece of a different color chalk, I made a series of half width stripes, half as far apart. I used a corresponding piece of cardboard with a narrower slit. I made narrow sripes at the wide spacing. I used the narrow slit cardboard, and then the wider slit cardboard, "Maybe a little weaak, but it should do." Then I made narrow stripes down the middle of the end of the wide stripes. I used the narrow slit cardboard. "Looks fine." Then I used the wide slit cardboard. "What is this mess??" Then, I made the students describe how to make a 48tpi disk with a 96tpi drive. -- Grumpy Ol' Fred cisin(a)xenosoft.com