English: A drawing of a corner reflector UHF television antenna from a 1954 advertisement in an electronics magazine. The corner reflector was a common antenna used for analog UHF TV reception. It consists of a "bow tie" dipoledriven element made of a pair of sheet metal triangles suspended between two flat rectangular metal grill reflecting surfaces at an angle of 90°. The corner reflector's advantages were a high gain of 12-15 dBi, a large front-to-back ratio, and a wide bandwidth, much wider than the Yagi antenna.
Alterations to image: Cropped out the rest of the advertisement. Cloned in a little of the reflector screen in upper left corner where it was obscured by other picture elements. Added shading to bow-tie dipole to make its shape clearer.
This image is from an advertisement for Walsco Electronics Corp. without a copyright notice published in a 1954 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.