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[Lear radio compass]
Photograph of a Lear radio compass, circa 1931-1939.
[Lear Developments telephone transmitter]
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]
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]
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]
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]
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]
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."
[Chassis of Model L Lear-o-Scope]
Photograph of the chassis of a Model L Lear-o-Scope, circa 1931-1939. The verso inscription, which was written by William P. Lear, describes the development of the device.Inscription on verso: "Here is chassis of Model L Lear-o-Scope. The layout was done by WPL -- Wilbur Webb - now deceased who left me and went to Bendix - and Fred [Coombs?] who could layout and draw up such a unit in a maximum of…
[Model L Lear-o-Scope and loop antenna]
Photograph of a Model L Lear-o-Scope and loop antenna, circa 1936-1939. The verso inscription, which was written by William P. Lear, describes the device and its development.Inscription on verso: "Note left crank changed bands and moved mash on dial -- Right crank for tuning -- moved freq. dial 200 to 410 KC -- 530 to 1530 KC. Also first time tuning meter used. High Z loop with short tuning coil…
[Learadio Model R-3 aircraft receiver, antenna, and peripheral components]
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…