Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!swrinde!zaphod.mps.ohio-state.edu!magnus.acs.ohio-state.edu!tut.cis.ohio-state.edu!ucbvax!PENNDRLS.UPENN.EDU!GTHEALL From: GTHEALL@PENNDRLS.UPENN.EDU (George A. Theall) Newsgroups: comp.sys.dec.micro Subject: Rainbow EchoMail Digest Message-ID: <9103230131.AA04966@remote.dccs.upenn.edu> Date: 23 Mar 91 01:32:00 GMT Sender: daemon@ucbvax.BERKELEY.EDU Organization: The Internet Lines: 159 Rainbow EchoMail Digest Mar 22, 1991 In this issue: FLOPPY DISKETTE DENSITIES (3 messages) RE: QUESTION RE: FLOPPY DISKETTE DENSI Articles posted to either INFO-DEC-MICRO or comp.sys.dec.micro are currently gatewayed to the Rainbow Echo on FidoNet. You do not need to take special action to respond to articles in these digests. Please send reports of problems or suggestions for improvement of this digest to GTHEALL@PENNDRLS.UPENN.EDU (Internet). ------------------------------------------------------------------------ Date: 19 Mar 91 11:03 -0500 From: NOLAN LEE To: HOWARD HALL Subject: FLOPPY DISKETTE DENSITIES In a message of , Howard Hall (1:109/417) writes: HH>example, that I only need SS (single sided) diskettes for my HH>Rainbow, but I get DS (double sided) so that I have a 'common' HH>diskette that I can easily reformat and use elsewhere. (I also HH>appreciate a dissertation on the need/usefulness of HD (high HH>density) diskettes in both the above categories. HH> HH> Help!! I use the least expensive diskettes I can find. I've been using the DSDD diskettes in the Rainbow and haven't had any problems with them. I've even punched new right protect notches and index holes and turned them over to double capacity with no problems. I tried using some of the high density disks in the Rainbow but had formatting problems with them. Even the ones that formatted ok still gave me read errors. I personally don't keep any disk with bad sectors. I usually bulk erase them and try the format over. Then mark them with a small "x" and send them as freebies to others that I give or trade files with. I don't trust 'em! After all, is it worth loosing an important file over a 25 cent disk? Perhaps someone else will have some suggestions! Good luck, Nolan - --- QM v1.00 * Origin: Nolan's Point (1:390/2.7) ------------------------------ Date: 20 Mar 91 20:16 -0500 From: WARNER LOSH To: VAN VANHORN Subject: RE: QUESTION In a message of <17 Mar 91 09:53:27>, Van Vanhorn (1:343/30) writes: VV>When major applications came on two 3740 disks (Single Sided Single VV>Density 8" floppies for any latecomers ) and ten meg hard drives VV>were still big, advertisers playing fast and loose with this difference VV>weren't a big deal. Besides, at 10 megs, it isn't much difference. At VV>64 megs, it is substantial. This discussion cam up a while ago. When you buy memory, 1K is 1024 and 1M is 1024K. However, when you buy a disk, however, 1K is 1000 and 1M is 1000K. I have spent several lunches arguing over this with someone that worked in the disk depratment were I work. These hair split by... Warner "Imp" Losh - --- msged 1.99S ZTC * Origin: DinoPoint 6 (1:104/114.6) ------------------------------ Date: 20 Mar 91 20:19 -0500 From: WARNER LOSH To: HOWARD HALL Subject: FLOPPY DISKETTE DENSITIES 5.25" Disks: Double Density: 40 tracks (Original PC disks) Quad Density: 80 tracks (Rainbow Disks) High Density: 80 tracks (AT disks) Note that HD and QD are different. The megetic properties of the disks are different, so don't use HD disks in a Rainbow (unless you like trouble). It is OK to use QD disks on an AT disk drive, since the head field is stronger than the specs. DD disks are OK to use in QD drives usually. They aren't tested and certified for 80 tracks, but will usually work. 3.5" Disks: DD: 80 Tracks (Original 3.5" disks) HD: 80 Tracks (New 3.5" disks) HD have 18 (or 20) sectors per track. DD have 9 (or 10) sectors per track. All HD disks write at a higher density and with faster data transfer rates than DD disks. As such, I have not found a way to put any HD disks in a Rainbow. Warner - --- msged 1.99S ZTC * Origin: DinoPoint 6 (1:104/114.6) ------------------------------ Date: 20 Mar 91 20:41 -0500 From: HOWARD HALL To: NOLAN LEE Subject: RE: FLOPPY DISKETTE DENSI Nolan- Your response received and appreciated. Your comments have clarified some of the verbiage in the catalog blurbs concerning diskettes, densities, capacities, etc. Based on your observations "in the field", I see no advantage to my testing of the same items! I will simply continue using the DS/DD, and may eventually even try the re-notch bit for some "casual" uses! Thanx! hlh - --- Opus-CBCS 1.14 * Origin: Silver Bullet - Silver Spring, Md - 301-622-2247 (1:109/417.0) ------------------------------ Date: 22 Mar 91 19:36 -0500 From: GEORGE THEALL To: WARNER LOSH Subject: FLOPPY DISKETTE DENSITIES WL>5.25" Disks: ... WL> Quad Density: 80 tracks (Rainbow Disks) WL> High Density: 80 tracks (AT disks) Warner, aren't the RX50s 96 tracks (per inch)? And, btw, ever notice that DEC in their _Rainbow Handbook_ describes them as "double density"? No kidding, I'm looking in the Spring 1984 edition, p. 8-17. Typo maybe? George ------------------------------ End of Rainbow EchoMail Digest ******************************