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Photoelectric ray to determine flying ceiling. Washington, D.C., June 15. To permit a ground observer to determine at what height flying is safe during days of fog and heavy overcast, Miss Elizabeth M. Zandonini, of the Radio Section staff of the Bureau of Standards, is shown with the balloon transmitting equipment. A photoelectric cell measuring light brightness is used to control the pitch of the radio signal transmitted from the balloon as it ascends. A graphical frequency recorder plots the pitch and hence [...] a measure of the light brightness as a function [...] height. The experiments are carried on for the U.S. [...]

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Photoelectric ray to determine flying ceiling. Washington, D.C., June 15. To permit a ground observer to determine at what height flying is safe during days of fog and heavy overcast, Miss Elizabeth M. Zandonini, of the Radio Section staff of the Bureau of Standards, is shown with the balloon transmitting equipment. A photoelectric cell measuring light brightness is used to control the pitch of the radio signal transmitted from the balloon as it ascends. A graphical frequency recorder plots the pitch and hence [...] a measure of the light brightness as a function [...] height. The experiments are carried on for the U.S. [...]

description

Summary

A black and white photo of a woman putting something in a box.

Public domain portrait photograph, free to use, no copyright restrictions image - Picryl description

date_range

Date

01/01/1937
person

Contributors

Harris & Ewing, photographer
place

Location

Washington, District of Columbia, United States38.90719, -77.03687
Google Map of 38.9071923, -77.03687070000001
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Source

Library of Congress
copyright

Copyright info

No known restrictions on publication.

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