Siemens Nixdorf 20 Test Note

Siemens Nixdorf Informationssysteme AG produced test notes like this one for internal calibration of their currency-handling machines — ATMs, sorters, and validators — rather than for any monetary purpose. The notes were engineered to precise mechanical tolerances so that equipment could be tested and certified without cycling real banknotes through thousands of repetitions of wear and sensor checks.

Siemens Nixdorf itself existed only between 1990 and 1996, when Siemens AG acquired the struggling Nixdorf Computer AG and later spun off the merged entity as Wincor Nixdorf. That narrow corporate window dates this piece fairly tightly.