Browse Items (1093 total)

Photograph of a swept antenna on the underside of a Fairchild 24 aircraft, circa 1939. A person, mostly out of frame, points to the antenna from the image's left side.Inscription: "First swept antenna on Fairchild 24. 1939."

Brochure for the Learadio Model UT-6 radio transmitter, circa 1939.

Brochure for the Learadio Model T30-R3AB aircraft transmitter-receiver, circa 1939.

Radio receiver constructed out of a metal case covered in brown and tan tweed leatherette fabric with 5 brown stripes. Circular speaker opening covered with brown mesh. Leather handle at top is detached. Black metal face with red and green Broadcast…

Report about the Lear Developments automatic landing field orientation device, June 1939. Contains technical details about the device. Three typed pages on Learadio letterhead.

Letter to Mr. J. K. Whanger, Lawrence Scudder and Company, from Richard A. Marsen, Lear Developments, June 19, 1939. Provides a "general outline of the patent situation at Lear Developments." Seven typed pages and original folder labeled "L-r2 /…

Letter to William P. Lear from Richard A. Marsen, June 20, 1939. Recommends that the company take a more general tone when announcing and publicizing products in order to protect Lear Developments' patents. References an Associated Press release…

Items from Box 4, Folder 27 of the William P. and Moya Olsen Lear Papers, August 1939. Includes eight pages of handwritten notes and sketches related to "Blind approach by voice," an airplane landing system.

Items from Box 34, Folder 1 of the William P. and Moya Olsen Lear Papers, December 1939. Contains handwritten notes and sketches about the Lear low approach system. All or most of the notes appear to have been written by William P. Lear. Five total…

Items from Box 4, Folder 23; Box 200, Folder 1; and Box 209, Folder 1 of the William P. and Moya Olsen Lear Papers, February 1939 to March 1940. Contains notes and diagrams related to ADF-6 and ADF-7 automatic direction finders. 11 total items.