Teledisk is a program which reads a floppy diskette into an image file on the PC, and can recreate a nearly exact copy of the floppy at a later date from that image file. For many years, Teledisk was the only program like this which could handle non-PC formats, and it became the primary method by which people preserved and exchanged system disks for classic computers.
Originally sold as a shareware product by a company called Sydex, all rights to Teledisk were later sold to NTI, who no longer supports it or offers it for sale. This puts Teledisk into a state of limbo, as you cannot legally obtain or use later NTI versions, and the Sydex shareware versions cannot be used beyond the evaluation period without a purchased license, which you currently cannot buy. This is one of several reasons I created ImageDisk as a replacement for Teledisk. I urge anyone creating or manipulating new diskette images to use ImageDisk instead of Teledisk.
Due to it's past popularity, it is likely that some of the diskette images you need for your classic system may be available in .TD0 (Teledisk) format. Teledisk also has a reputation for having compatibility issues between versions, and with different PC hardware. To help you try and recover any .TD0 images that you encounter, I have collected all of the shareware versions of Teledisk that I have been able to find and placed them here.
Teledisk uses a closed/undocumented image file format, which means that the only official way to access .TD0 images is with Teledisk. The ImageDisk .IMD format is open and fully documented, if you convert .TD0 images to .IMD, you will always have the ability to explore other means of accessing the diskette content. To assist in converting existing Teledisk .TD0 images to ImageDisk .IMD format, I have created two utilities, TD02IMD and TD2IMD which are included with the current version of ImageDisk.
Please respect the Sydex/NTI license/prohibition, and use these only to recover existing .TD0 images within the limits of the shareware evaluation period. ImageDisk is available and recommended for all new PC diskette imaging.
Teledisk 1.05 (contains some .TD0 info) Teledisk 2.00 Teledisk 2.01 Teledisk 2.10 Teledisk 2.11 Teledisk 2.11 (different executable) Teledisk 2.12 Teledisk 2.13 Teledisk 2.14 Teledisk 2.15 Teledisk 2.16 (EXE only) My notes on .TD0 file. (25k .TXT)