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Keywords from Image Description:
Vacuum tubes multilingual.svg Beschreibung own work edit the german version org Vacuumtubes svg Inkscape November UTC De Nobelium org Vacuumtubes svg german Glasrhre evakuiert Glass envelope evacuated Enveloppe de verre evacue Heizspannung Heater voltage Tension du chauffage Kathode negativ Cathode negative Cathode