working ORIGINALS. Backups made with other copiers can't be backed
      up. You may back up second generations of backups made with this
      system, but you must use the RLV0 copier with the correct track
      sequences (again, use the scanner). The original protection scheme
      is flakey in loading and the copies are no better (sorry).
      

                INTRO : PROTECTION SCHEME TYPE I
      
      GEOS (Graphic Environment Operating System), from Berkeley
      Softworks, has revolutionized the way people use their C-64s. It's
      icon-based, user-friendly, desktop interface has extended the life
      of this machine to 1990 and lured leery buyers into the world of
      Commodore computing. With the newly available 1764 RAM expansion,
      GEOS will allow a C-64 to approach the capabilities of its younger,
      but more powerful brother, the C-128.
      
      But unlike other operating systems (CP/M, MS-DOS..), GEOS is
      copy-protected. Who needs a copy-protected operating system? What
      if you own a large selection of GEOS application programs and your
      GEOS original crashes? The programs are useless while you try to
      attain a replacement and you can't borrow a friend's copy because
      of the serial number protection! Clearly, it benefits only
      Berkeley.
      
      Meanwhile, we've been agonizing over which Berkeley releases to
      cover in this edition of Kracker Jax Revealed. We were reasonably
      sure that most of you would own GEOS v1.2 and Deskpak I, so we've
      included those. PLUS a quick-n-dirty way to defeat GEOS v1.3's
      "Trojan horse" scheme, which will erase your system files if the
      file "GEOSBoot" fails a checksum test. GEOS v1.3's protection might
      be covered in a future edition if readers demand it, but its
      complexity might be intimidating to some.
      
      Be forewarned, though, that the going will be tough if you aren't
      familiar with "The Official GEOS Programmer's Reference Guide" or
      Richard Immers/Gerald Neufeld's "Inside Commodore DOS". GEOS and
      it's protection schemes are heavily I/O bound and good working
      knowledge of the 1541 drive and GEOS KERNAL routines is essential
      to understanding the following articles.
      
      Please note:
      GEOS, GEOS v1.2, Deskpak I, GEOS v1.3, Berkeley Softworks, and
      The Official GEOS Programmer's Guide are all registered trademarks
      of Berkeley Softworks.
      
            K.J. REVEALED TRILOGY    PAGE [94]     (C)1990 K.J.P.B.