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24 results
Items from Box 4, Folder 6 of the William P. and Moya Olsen Lear Papers, September to October 1939. Folder contains assorted items related to the Learadio Airport Localizer (L-P-2), including summaries, correspondence, diagrams, sketches, a clipping, and a Library of Congress certificate of copyright. 14 total documents and original folder labeled "L-p2 / 'Learadio Airport Localizer.'"
Items from Box 1, Folder 15 and Box 209, Folder 1 of the William P. and Moya Olsen Lear Papers, June 1935 to November 1944. Contains drafts, notes, and technical drawings for the radio guidance system and blind approach system (WPL/30-1) patent. Twenty total items.
Items from Box 4, Folder 3 of the William P. and Moya Olsen Lear Papers, circa 1937-1938. Contains an advertisement for the Learadio Compass, an advertisement for the Learadio AMRL-1 Marine Radio Direction Finder, and a brochure for Learadio products.
Items from Box 18, Folder 1 of the William P. and Moya Olsen Lear Papers, circa 1940-1943. Contains a patent application and other documents related to the Radio Automatic Guidance System (Case 31-3) and Loop Antenna System (Can. 8-1), as well as a manual titled "The Lear-Matic: The ultimate instrument for aircraft navigation." 15 total documents.
Photograph of Learadio radio and navigation equipment, consisting of a transmitter, receiver, and direction finder, circa 1936-1939. The verso caption notes that this equipment was developed by "myself" (William P. Lear) and Reeder Nichols for the London to Melbourne Air Race.Caption on verso: "S. This is the equipment that was built up in the 60 days in our organization at 123 W. 17th St. NYC, by…
Photograph of a Lear Developments aircraft transmitter, circa 1931-1939. The verso caption notes that this transmitter was developed for the Flight International Corporation and describes the device's components and specifications.Typed caption on verso: "K. This is an aircraft transmitter designed for International Flight Corporation and was the first transmitter, I believe, that was ever…
Photograph of a Lear Developments BC-190-T5 radio transmitter, circa 1940. The verso inscription notes that this transmitter was developed for the U.S. Army Signal Corps and describes the device's components and specifications.Inscription on verso: "45 kc to 13 mc 50 watt trans. 4 [illegible] and master osc [oscillator]. Designed about 1940 in Vandalia for first AC operated aircraft of Signal…
Photograph of a Lear Developments Type T-120 transmitter, circa 1936-1939. The caption on verso notes that transmitter was developed for the Royal Canadian Air Force and describes the device's components and specifications. Caption on verso: "J. This transmitter/receiver combination was designed for the Canadian RAF and called the Type T-120, built around 1936-37 and was essentially an R3 receiver…
Photograph of a Learadio airport telephone transmitter, circa 1931-1939. Inscription: "This 15-watt power transmitter was habitually able to work aircraft 250 miles away. Freq. 278 kc."
[Learadio R3AB receiver]
(Item)
Photograph of a Learadio R3AB receiver, circa 1937-1939. Inscription: "Ground station designed for foreign use 1937-193[cut off]."