Image / Erla Balloon Circloid coupler 200-550M

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Title: Erla Balloon Circloid coupler 200-550M
Creator: Electrical Research Laboratories Inc. (Chicago, Ill.)
Date Created and/or Issued: 1925-1930
Contributing Institution: History San Jose Research Library
Collection: History San Jose Online Catalog
Rights Information: Please contact the contributing institution for more information regarding the copyright status of this object.
Description: Typical "doughnut" coil of the late 1920s for amateur radio construction. Used as an inductor for tuned RF circuits. This construction confined the field within the coil, thus eliminating the need for shielding to prevent feedback between stages. Usually used in sets of three.
Type: Image
Identifier: 592FDD7D-3E2C-4FF8-A72A-743443851474
2003-1-671
Subject: Amateur radio stations (LCSH)
Radio--Equipment and supplies (LCSH)
Radio--Receivers and reception (LCSH)
Nineteen twenties (LCSH)

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