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• Still Image (5)

• composite photographs (5)
• photographic prints (5)

• Copyright undetermined (5)

• Radio in aeronautics (5)
• Aids to air navigation (4)
• Lear Developments (4)
• Learadio (3)
• Radio--Transmitters and transmission (3)
• Antennas (Electronics) (1)
• Radio direction finders (1)
• United States. Department of Commerce (1)

5 results

[Lear Developments telephone transmitter] (Item)

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…

[Learadio combination motor generator and transmitter] (Item)

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…

[Lear Developments radio receiver] (Item)

Composite photograph of a Lear Developments radio receiver, showing views of the internal components and the external case, circa 1931-1939. The caption notes that this device was developed for the U.S. Department of Commerce.Typed caption on verso: "U. This is, I believe, a Dept. of Commerce aircraft receiver designed for loud speaker operations and headphones, which covered the bands of 200-400…

[Learadio loop antenna] (Item)

Composite photograph of a Learadio loop antenna, showing two views of the internal components, circa 1931-1939. The caption describes the antenna's development and specifications.Typed caption on verso: "H. Shows an early attempt to tune the loop antenna at the antenna, itself, to eliminate the losses attendant to a long loop line. Also you will note that there were two loops in the fore and aft…

[Learadio panel assembly] (Item)

Composite photograph of Learadio panel assembly, showing side and front views, circa 1940s-1950s. Individual components include a fixed antenna tuning unit, trasmitter, automatic direction finder, and control unit.Caption: "Front view / NA-44 / Learadio panel assembly. 201171/25."