Now, after more than 15 (!) years, IBM compatible personal computers (PC) with WINDOWS as operating system can still not compete with the unforgettable ATARI ST ;)
But because WINDOWS became unfortunately something like a world standard, some users may wish to convert their ATARI documents to a WINDOWS compatible form.
Even both operating systems work with 3.5'' disks and Ataris file system is almost identical to Microsofts FAT 21, the internal disk formats are not fully exchangeable. DOS or WINDOWS can not read TOS formatted disks. There are ATARI programs like CONVERT, which can create DOS formatted disks with an ATARI drive, but my desktop PC and my IBM ThinkPad could not read or write such disks.
On the other hand, my ATARI ST could read and write on HD disks, which were formatted 720 Kb under WINDOWS 98. So, if you still have an active ST, you can use this method to copy files from ATARI formatted disks or the ST hard disk to the WINDOWS formatted disk and transfer them to your PC hard disk.
It is easy, if you have still a working ATARI. The ASCII codes of TOS and WINDOWS are similar, but there are differences for special characters. The ATARI program TEXTO (version 2.0) should convert TOS ASCII to WINDOWS ASCII or HTML, but TEXTO did not run on my emulators. But you can just use the above described method to copy your documents to your PC and open them with MICROSOFT OFFICE WORD, NOTEPAD or WORDPAD. This works with ASCII and with 1ST WORD PLUS documents. All you need to do is to fix special characters (such as the German umlauts) with "Find and Replace" and to format your text manually.
If you do not have an active ST, you can not read your TOS formatted disks with WINDOWS. In this case, the only way is to install an ST emulator on your PC and to run 1ST WORD PLUS on your PC. You can then read, edit or print your docs, but not convert to OFFICE files.
Signum is likely to be so far the best scientific text processing program ever written. But because OFFICE developed somehow to the standard for office software, caused by its market power and not by a convincing performance, some people may want to convert SDO documents to a WINDOWS compatible format.
Unfortunately, I found during my investigation no way to make SIGNUM documents readable on my PC. Is it of cause possible to save such docs by the above described method on a WINDOWS formatted disk or on the PC hard disk, but no PC program can understand the encoding. I was also not successful to run SIGNUM 2 on any emulator because of its copy protection (SIGNUM uses direct access to the ATARI hardware). The only way, to save at least the pure text information without any formatting or embedded graphics, is to load the SDO document on an ATARI in SIGNUM and to save it as an ASCII file on a WINDOWS formatted disk.
This is the easiest way. Just run and enjoy the ATARI programs on an IBM compatible personal computer. You can download free emulators from the internet:
STEEM (STE Emulation Machine)
PACIFIST on the "Little Green desktop"
You need also to download TOS before you can use them (rename the file, e.g. "Tos206de.img" to "TOS.img" before you load it in GEMULATOR).
(To my surprise, even a emulator for my first computer SINCLAIR ZX SPECTRUM is available in the Internet.)
I tested STEEM v1.62 (now also version 2 available) and GEMULATOR 2000 v8.03 with WINDOWS 98 and WINDOWS 98 MILLENNIUM and found both running well. STEEM can read only disk images (special WINDOWS files, which simulates an ATARI disk), GEMULATOR also most ATARI formatted disks (in my case only DS DD, but not SS DD). GEMULATOR has furthermore the option to read or write WINDOWS formatted files (e.g. on disks as described in the above paragraph or on the PC hard disk), but it cannot covert from ATARI to WINDOWS format. But you can create a disk image from your ATARI disk (does not work always) and save it on your PC hard disk, that you does not need to work with your disks all the time.
Emulators are good to run games or programs like 1St WORD PLUS or GFA BASIC (you can run or edit your own GFA programs). Emulators do not work with copy protected programs like SIGNUM.