The image features a SCR Apparatus, specifically the 55 Vacuum tube receiver. The photograph was taken by Photographer 2618 on March 5, 1918. This apparatus refers to a detector set utilizing vacuum tubes. The image is not intended for publication, and it is associated with laboratory notes referencing its serial number, which is $2618.

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Size: 7982px × 6302px
Photo credit: © piemags/NSC / Alamy / Afripics
License: Licensed
Model Released: No

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