Research Inc Model 73221 Micro Data Trak I O Programming Interface 12401

  For sale is a Research, Inc. Model 73221 Micro Data-Trak Serial
  ASCII I/O Programming Interface.  This unit has indicator lamps
  for: A1 Span / Zero / A2 Span / Zero.  These lamps are behind the
  hinged aluminum bar on the unit's face, and are not pictured here.
  Condition appears very good.

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