scription and photograph of an SCR apparatus, specifically the SCR 72 low frequency amplifier. This image is from March 5, 1918 and is not meant for publication.

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

Keywords: 5, 1918, activities, american, amplifier, apparatus, frequency, labo, march, military, photograph, photographer, reco, scr, war, world