If you get an ancient copy of NU (Norton Utilities) you have all you need. Simply go to the Edit section, select drive A: and open the disk editor: the boot sector data of your floppy will be shown to you. Now, change the three first bytes (normally 00 00 00 on an ST disk) into EB 29 90 and confirm.
Exit Norton Utilities and issue the "dir" command at the DOS prompt.
