The Cover of Input- & Counter-Unit is removed ...

... and also the Cover on front.

The calculator came in bad shape:
The BLACK "6"-KEY & the "X"-KEY ( on the right ) were missing
Temporarily replacement for the MISSING CRANK:
A handle from a toilet flush is used!

The Replacement Parts in process  ( see Remarks ) ...

Detail View of the ADAPTING SEGMENT in Action:
Keys 1-2-3-4-5-6-7-8-9 are pressed ...

The MARCHANT company got in  PATENT TROUBLES  with the  ODHNER  company using
"Pin Wheels".  Employee Carl M.F. FRIDEN ( later he founded his own company )
designed  a new type of  calculators  using  Adapting Segment / StellSegment
Coding.  The keyboard pre-sets the gears of the INPUT UNIT ...


... and with the turn of the MAIN CRANK this gears get moved radially so, that
only the appropriate number of teeth turn the gears in the ARITHMETIC UNIT.
( The sketch doesn't show the locking of a pressed-down key )

               Back to the MARCHANT-H9 Main Page ...

R E M A R K S :         6th »BBST«  in the ENERGIE-MUSEUM  on 9th October 2010
Demonstration of this Calculator at the »Berlin-Brandenburger Sammler-Treffen«

Special  "THANKS!"  to the  labs  of my university  for their contributions in
restoring this MARCHANT for this event - AND! - for their friendly  assistence
in former times:  Always making the impossible possible ... 

Fachbereich  » Informatik & Medien «
   Prof.Dr.Bernhard Buchholz,
   Andreas Doepkens & Brian Schueler          Labor »Prozess- & Systemtechnik«
   Andreas Graebe                              Labor »Automatisierungstechnik«
Fachbereich  » Elektro- & Feinwerktechnik «
   Thorsten Sohr                      Labor »Geraetetechnik, Optik & Sensorik«
Fachbereich  » Maschinenbau, Verfahrens- & Umwelttechnik «
   Mario Schubert                   Labor »Kunststoffverarbeitung & -pruefung«
   Andre Zuehlsdorf & Frank Hauser                  »Labor Produktionstechnik«

© C.HAMANN              10/10/2010