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Summary
DescriptionAntenna of WOR-AM.jpg
English: Antenna of AM radio station WOR in Newark, New Jersey, from an advertisement in a 1935 magazine. It is a T antenna consisting of a horizontal wire suspended by insulators between two towers, with a vertical wire hanging down from the center. The power from the transmitter is applied between the bottom of the vertical element and a ground connection.
Alterations to image: cloned in center portions of antenna wire and sky obscured by advertising copy.
This image is from an advertisement by Isolantite, Inc. without a copyright notice published in a 1935 magazine. In the United States, advertisements published in collective works (magazines and newspapers) are not covered by the copyright notice for the entire collective work. (See U.S. Copyright Office Circular 3, "Copyright Notice", page 3, "Contributions to Collective Works".) Since the advertisement was published before 1978 without a copyright notice, it falls into the public domain.
Note that it may still be copyrighted in jurisdictions that do not apply the rule of the shorter term for US works (depending on the date of the author's death), such as Canada (50 p.m.a.), Mainland China (50 p.m.a., not Hong Kong or Macao), Germany (70 p.m.a.), Mexico (100 p.m.a.), Switzerland (70 p.m.a.), and other countries with individual treaties.