the Mountain Computer Expansion Box
   a legendary expansion to the Apple ][ series

  reverse engineered and de-mystified

   Page No.:H054-2
      Copyright note: The pictures used in this page, have been taken from members gsmcten, macnoyd* and Keatah ( all members at the Applefritter Forum )
                              * the pictures from macnoyd, result from the ebay offer he successfully won
                                 Therefor the copyrights of the pictures displayed at this page remain of course to the members at AF whom the units belong.
                                 The other pictures here resulting from the reengineering process remain with their copyright to me and none of the contents from this
                                 page may be used ( not even partially ) in any other webpage without the permission of the copyright owners.

 The Analysis:

  After i  recieved the huge pile of pictures from Keatah, i was enabled to start drawing the films of the interface card and the mainboard.
  This was needed to uncover the traces between the single components - as preliminary condition to draw a circuitplan for both units.
  The circuitplan as target was the intro to any person, who owns such a unit and needs to perform a repair or maintenance of that units.
  A deeper understanding of the functions ( in other words : how the units interact with each other, how the control-lines rule the box
  and how the Apple accesses the cards inserted in the box - is without the circuitplan impossible. Any repair without circuitplan is just
  an attempt to guessing around.

  In the mean time at this stage just the accident happened - as like just to proof this arguments... - the box that gsmcten had purchased
  several weeks before failed and demanded for a repair.

  The following pictures and drawings on the page result from the pile of pictures and from several revisions and corrections.
  They display all traces on the mainboard and the interfacecard at the solderingside and the "hidden" traces beneath the components
  on the componentside and the resulting circuitplans as final outcome from the pictures taken from Keatah and from measurements
  Keatah has taken to detect those parts of "hidden" traces that turned out to become difficult for detection:

   So lets start here first with the interface card and then continue to the mainboard:
  here the traces of the interfacecard at the solderingside:

  here the traces of the interfacecard at the componentside::

  here the traces mounted together in layers to perform controlling on pins not connected like unused pins on the ICīs:

   and finally here the circuitplan of the interfacecard resulting from that picture above:

  here we continue with the Mainboard:
  Here we start with the traces of the mainboard from the solderingside  :

  and here is the plan of the traces of the mainboard from the componentsside:

  here we have the combined drawing from both layers ( solderingside and componentside ):

  and finally here the resulting ( from the previous drawing ) circuitplan of the mainboard:

  Remark: in a later page i will also issue a lot of pictures with details of the box and the interfacecards. That shall also enable the reader to see which kind of
                   components have been used, when forced by repair demands to replace such components.

  The next page will start with analysis of the data resolved up to this point. The following page target to enable the owners to understand the function of the
  units. Therefor i will start splitting the groups of components to function groups explaining how they interact with each other.
   here is the link to the next page - where the story is continued =>
 <= here is the link back to the previous page

 <= here is the links to turn back to the indexpage of the Applebox
       due to european laws and german court decision:
 I hereby declare no responsibility to any "deep links" resulting from the links in this page. I have no influence to the pages linked hereby in this page and the
 contents in those pages. I therefor canīt take any kind of responsibility to contents in the pages, where these links direct the readers browser to nor to the
 contents resulting from following up links from those pages. The reference to contents by this links is dependent ro the status of the date when the links have
 been set ( April 2013 ) and it might occur that references and contents may change by the fact that domains may have been discontinued from their former owners.
 In such cases i canīt take any kind of responsibility to the changed contents. this is specialy valid to banners, advertisements or merchandising links in the targeted