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21 results
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.
Items from Box 27, Folder 23 of the William P. and Moya Olsen Lear Papers, July 24, 1941. Contains a press release and eight captioned photographs related to William P. Lear's evaluation of German radio equipment taken from a captured Messerschmitt Bf 109 aircraft. The photographs depict Lear and Lear Avia engineers carrying out tests on the radio equipment, as well as close-up shots of the…
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]."
[Learadio T-40 transmitter]
(Item)
Photograph of a Learadio T-40 transmitter, circa 1935-1939. Inscription: "T40 6 freq. transmitter designed for D.O.C. (FAA). 1935."
Composite photograph of a Lear Developments telephone transmitter, showing views of the internal components and the external case, circa 1931-1939. The verso inscription, which was written by William P. Lear, states that this was the first 3105-3120 kc 35-watt telephone transmitter made for private pilots.Inscription on verso: "The first 3105-3120 KC 35 watt telephone transmitter ever made for…