Search Digital Records

• Subject > Aids to air navigation (remove)
• Subject > Radio in aeronautics (remove)

Limit your search

• Still Image (41)
• Text (5)
• Mixed Materials (4)

• New York (N.Y.) (1)
• New York (State) (1)
• United States (1)

• photographic prints (41)
• composite photographs (4)
• brochures (2)
• patents (2)
• advertisements (1)
• booklets (1)
• mixed materials (1)
• pamphlets (1)
• posters (1)
• press releases (1)
• reports (1)
• speeches (documents) (1)
• technical drawings (1)

• Copyright undetermined (36)
• In copyright (14)

• Aids to air navigation (50)
• Radio in aeronautics (50)
• Learadio (37)
• Lear Developments (27)
• Radio--Transmitters and transmission (20)
• Radio direction finders (6)
• Antennas (Electronics) (5)
• Lear, William P. (William Powell), 1902-1978 (5)
• Airplanes--Cockpits (4)
• Lear Avia Corporation (2)
• Lear, Inc. (2)
• Aviation Writers Association (1)
• Canada. Royal Canadian Air Force (1)
• Inventions (1)
• Lear Avia, Inc. (1)
• MacRobertson International Air Race (1934) (1)
• Nichols, Nichols, Reeder Glen, 1904-1975 (1)
• Ontario. Department of Lands and Forests. Forestry Branch (1)
• Pangborn, Clyde Edward, approximately 1893-1958 (1)
• Ross, Betsy (1)
• Turner, Roscoe, 1895-1970 (1)
• United States. Army. Signal Corps (1)
• Women air pilots (1)
• Women in aviation (1)

50 results

[Lear Developments Type T-120 transmitter] (Item)

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…

[Learadio airport telephone transmitter] (Item)

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."

[Lear radio compass] (Item)

Photograph of a Lear radio compass, circa 1931-1939.

[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…

[Lear Developments special aircraft receiver and remote control unit] (Item)

Photograph of a Lear Developments special aircraft receiver and remote control unit (radio transmitter Type L-35S-1), circa 1931-1939. The verso caption notes that the receiver was developed for the Ontario Forestry Branch and describes the device's components and specifications. Typed caption on verso: "V. The control head for the Ontario Forestry Branch of the Dept. of Lands and Forests of…

[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…

[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."