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SR 52Model: SR-52
Battery: 3 x AA
Adapter: AC9130A or DC9105
Year: 1975
Chip: TMC0501 / 0524 /0595 / 2xTMC0599, 2xTMC0561/0562
Manual: with permission www.datamath.org
  basic library
      
   

Info: classic second GENERATION