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GR type 722-D precision variable capacitor
GR type 722-D precision variable capacitor

GR type 722-D precision variable capacitor

Datecirca 1955
Inventory NumberRS0225
ClassificationCapacitor
Subject
    Maker General Radio Company 1915-present
    User Cruft Laboratory, Harvard University founded 1914
    Cultural Region
      Place of Origin
        Dimensions30 x 29 x 28 cm (11 13/16 x 11 7/16 x 11 in.)
        Material
          Accessories2 small rusted keys.
          DescriptionA General Radio Co. type 722D, serial number 845, precision variable capacitor, encased in a wooden box.
          In Collection(s)
          Signedetched and white filled on front of instrument, top right: PRECISION / CONDENSER / 100 & 1100 (greek letter mu) (greek letter mu) f / TYPE 722-D SERIAL NO. 845 / GENERAL RADIO CO. / CAMBRIDGE MASS. U.S.A.
          Inscribedstamped on carrying crate: CRUFT INSTRUCTION
          FunctionPossible function: a stable and precise variable air capacitor intended for use as a standard of capacitance.

          http://cgi.ebay.com/General-Radio-GenRad-722-ME-Precision-Capacitor_W0QQitemZ110271451671QQihZ001QQcategoryZ25399QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
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