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variable inductor
variable inductor

variable inductor

Date1890-1920
Inventory Number0295
ClassificationInductance
Subject
    Maker Hartmann & Braun AG 1879 - 1999
    Supplier James G. Biddle Company fl. 1890 - 1950
    Cultural Region
      Place of Origin
        Dimensions24.5 x 35 x 25 cm (9 5/8 x 13 3/4 x 9 13/16 in.)
        Material
          DescriptionFrom Instrument Card: "Moveable coil pivoted to turn inside a fixed coil. Hemisphere above and at right angles to the two coils with a scale of 0-160. Step switch with assorted readings to select various turns of the fixed coil. All mounted on veneered rectangular base with molded edge."
          Signedon dial: HARTMANN & BRAUN A.G. / FRANKFURT A.M. / No. 428
          Inscribedbase marked: James G. Biddle / Philadelphia; twice marked: PROPERTY OF / HARVARD ENGINEERING SCHOOL; HARVARD UNIVERSITY 1179
          FunctionFor experimentation and demonstration of the high voltages induced in a secondary winding when the current in the primary windings is abruptly disrupted.
          ProvenanceHarvard University Engineering School, removed to the collection November 1956.
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          Hartmann & Braun AG
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          Accessories: plugs (8)
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