Floppy disks that are recorded in conventional “FM” or “MFM” format can often be imaged, and images can be written back to real floppy disks, using commonly available older-model PCs and peripherals. This applies to disks recorded in the original IBM 3740 “FM” (single-density) specification, and those recorded in the IBM 34 “FM/MFM” (single density track 0 and double-density on all other tracks) specification. This includes for example most CP/M (including Kaypro) disks and most TRS-80 disks, other than early TRS-80 Model 1 disks that used non-standard data address marks.
Here is a PowerPoint presentation describing the process and the equipment required:
The technique described in this presentation won’t work for systems that use other encoding methods (such as Apple II disks and 8-bit Commodore 5.25″ disks, which both use GCR). More complex tools such as Kryoflux may be useful for these, but I have not verified this.
Dave Dunfield’s ImageDisk program (for MSDOS computers) can be downloaded here. I use this software extensively for disc imaging, particularly for my PDP-11 and S-100 computers.
The main manual that comes with ImageDisk (IMD.TXT) is also a valuable source of information for those wanting to learn more about disk imaging.