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25 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 4, Folder 30 of the William P. and Moya Olsen Lear Papers, circa 1931-1939. Contains two reports related to the Learadio Lear-O-Scope Model LC 100 Radio Compass Direction Finder.
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.
Composite photograph of a Learadio combination motor generator and transmitter, showing views of the internal components and the external case, circa 1935-1937. The verso caption states that this was one of the first transmitting devices for private pilots.
Typed caption on verso: "E. This is a combined motor generator and transmitter to operate on 3015 and 3120 KC. It was produced in quantities…
Photograph of various components for a Learadio T30R3 installation, circa 1931-1939. The verso caption describes the problems and capabilities of the trailing antenna.Typed caption on verso: "G. Shows a complete set of equipment for a T30R3 installation. You will note that the antenna consisting of a trailing rope that was always hanging out of the airplane without a weight on it, and the big…
Photograph of a Learadio Type TR-50 transmitter, showing views of the internal components and the external case, circa 1931-1939.Typed caption on verso: "T. Shows the original effort to make a more powerful transmitter by using tubed in parallel. This was a two-frequency transmitter and operated on 3105 and 3120 KCs."
Photograph of a Learadio aircraft communications system, circa 1931-1939. Specific devices pictured include the Model MOPA transmitter (emitator acord unit) and Model R2BB receiver (receptive accord unit).Caption: "Typical aircraft communication system."
Photograph of a Learadio Model R-3 aircraft receiver, shielded loop antenna, and peripheral components, circa 1931-1939. The caption describes the device's development.Typed caption on verso: "P. This loop was metallized in an attempt to shield it, but it was found that the metallizing reduced the 'Q' of the loop so much that it was completely impractical. It was also used in conjunction with an…
Photograph of a Learadio Model R1 receiver and headphones, circa 1931-1939. The device is on scale to demonstrate its light weight. The caption describes the device's development and specifications.Typed caption on verso: "C. A Model R-1 battery-operated receiver, which had very good sensitivity. As you can see, it weighs a little less than 16 1/2 lbs, complete with batteries and headphones. It is…
Photograph of a Learadio T-30 R3 radio system and assorted components, circa 1935-1939. The inscription notes that this equipment was developed especially for pilots operating in Alaska.Inscription: "Learadio T-30 R3. Saved many lives and much money for bush pilots in Alaska and northern Canada. Designed in 1935 especially for Alaska flyers. / Trans. 2-freq. -- 3105 6210 and others. Plug-in…