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• Subject > Radio--Transmitters and transmission (remove)
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• Still Image (17)

• photographic prints (17)
• composite photographs (3)

• Copyright undetermined (17)

• Radio in aeronautics (17)
• Radio--Transmitters and transmission (17)
• Aids to air navigation (16)
• Learadio (13)
• Lear Developments (10)
• Radio direction finders (2)
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17 results

[Various components for Learadio T30R3 installation] (Item)

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…

[Learadio Type TR-50 transmitter] (Item)

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."

[Learadio aircraft communications system] (Item)

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."

[Learadio remote controller and transmitter remote control] (Item)

Photograph of a Learadio remote controller and transmitter remote control, circa 1936. The caption describes the devices' specifications and utility.Typed caption on verso: "O. (circa 1936) A picture of both the combination remote controller and the transmitter remote control. You will note there were blank spaces on the transmitter selector dial to write in the particular frequencies of the…

[Learadio portable transceiver and travel case] (Item)

Photograph of a Learadio portable transceiver and travel case, circa 1931-1939.Inscription: "Portable transceiver for [illegible] use."

[Learadio equipment installed in front and rear cockpits] (Item)

Photograph of an unidentified aircraft fuselage with its side panel removed, showing the Learadio equipment installed in the front and rear cockpits, circa 1940s-1950s. Several of the components are labeled. Caption: "NA-44 / Learadio equipment installation / Front and rear cockpit -- Right side. 20-1171-27." Labeled components: "Direction indicator panel -- Rear cockpit. Automatic compass and…

[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."