Inside Out Library · ExploreThe principles underlying radio communication (1922)United States. National Bureau of Standards, Ould, Richard Sheldon, 1889-, United States. Army. Signal Corps · Washington, Govt. Print. Off. · leaf 388FiQ.20fl rtelix^ round wir« … FiO.20<7 SceC^ionAl view of-fUtsljnakWoynd <jf mat»t ripborvTelegraph, Wireless · RadioInternet Archive · Public Domain Mark 1.0. Free to use for anything.More pictures from The principles underlying radio communicationMore like this
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