Xref: utzoo comp.sys.ibm.pc.misc:10585 comp.sys.ibm.pc.hardware:10008 Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!hsi!genly!chris From: chris@genly.UUCP (Chris Hind Genly) Newsgroups: comp.sys.ibm.pc.misc,comp.sys.ibm.pc.hardware Subject: Floppies Message-ID: Date: 20 Jun 91 05:17:28 GMT Organization: Eggplant Software Tools, CT, USA Lines: 43 Thanks to all those that sent email anwering my questions about floppies. Here is a summary: 5 1/4 inch ---------- DS DD, 40 tracks, 9 sectors/track, 360K formatted DS HD, 80 tracks, , 1.2M formatted, 1.4(?) raw - Diskette case is identical for the DD and HD diskettes. There is no hole or slot in the case to distinguish between the two densities. - Coercivity of HD diskettes is about twice that of DD diskettes. So a DD drive cannot make enough signal impression on an HD diskette. - The HD track 0 is about .100" closer to the hub than the DD track 0. Many HD disks don't have acceptable media where track 0 of a DD diskette would be. 3 1/2 inch ---------- DS DD 80 tracks, 9 sectors/track, 720K formatted, 1M raw DS HD 80 tracks, 18 sectors/track, 1.44M formatted, 2M raw DS ED 2.88M formatted, 4M raw, requires DOS 5.0 and above. - DD and HD diskettes have roughly the same coercivities. - HD diskettes have a square hole in the plastic casing directly opposite from the write-protect hole. DD diskettes do not. * * * \|/ * _______ --O-- ____/ KC1VP \____ * /|\ * ______/ (203) 389-8680 \______ ______/ Eggplant Software Tools \________ ______/ 95 Fountain Terr., New Haven, CT, USA, 06515 \_______ / Chris Hind Genly chris@genly.uucp uunet!hsi!genly!chris \ ----------------------------------------------------------------