Building new S100 floppy system - test-drb@ccmp.vtda.org

21 May 2006

I have a 1977 SWPTC floppy disk system that uses the FD1771 controller. It 
came with Shugart SA400 drives and I upgraded to TM100. The stock controller 
card was single sided and it worked OK, You could use an existing latch on 
the SWTPC card to do side select.

You can also use current production 3.5 inch drives with it.
http://www.swtpc.com/mholley/35disk/Disk.htm

Michael Holley
www.swtpc.com/mholley

...
  From: "Richard A. Cini"
 Subject: Building new S100 floppy system

            I have several random parts I'm going to pull together to build
 a "new" floppy system for my IMSAI. I have an SD Sales Versafloppy
 controller card (which used the FD1771B controller) and several 5.25" 
 floppy
 drives (all soft sectored). The Versafloppy manual indicates that it will
 work with a Shugart SA400/450. When I look up the specs on the SA400, it
 indicates that the unformatted capacity is 109.6k and the formatted 
 capacity
 is 81k. I didn't read the entire manual but this look like SSSD specs.

            I of course don't have any floppy drives like this but I have
 several original PC drives (TM-100 and others) and several 360k drives of
 various types. 