Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.2 9/18/84; site brl-tgr.ARPA Path: utzoo!watmath!clyde!burl!ulysses!mhuxr!mhuxt!houxm!whuxl!whuxlm!akgua!gatech!seismo!brl-tgr!tgr!Kushall.henr@XEROX.ARPA From: Kushall.henr@XEROX.ARPA Newsgroups: net.micro.cpm Subject: Re: 40 track drives on Apple CP/M Message-ID: <1598@brl-tgr.ARPA> Date: Wed, 15-Jan-86 08:10:59 EST Article-I.D.: brl-tgr.1598 Posted: Wed Jan 15 08:10:59 1986 Date-Received: Fri, 17-Jan-86 06:28:14 EST Sender: news@brl-tgr.ARPA Lines: 14 Many of the early micro computer 5.25 inch floppy disk systems were based on the Shugart SA400 "mini floppy" drive. (For a while they were the only maker ie 1975) This was the original 5.25 inch drive. The SA400 could only have a maximum of 35 physical tracks. If you attempt to step to a track >34 the CAM follower would lift out of the grove. Later Shugart updated the drive design to 40 tracks, and 40 tracks has been standard on 5.25 inch drives for quite a while now. I don't know of any other companies that make 35 track drives. Shugart drives labled SA400 are 35 track drives, drives labled SA400L are 40 track drives. Also some early Shugart SA400's were single density. (I belive before 1977) The only way to tell these is by the serial numbers. Ed Kushall