A quartz crystal which controls an oscillator is placed in a chamber which may be evacuated. The output of the oscillator increases as the air pressure is reduced.
Proceedings of the Iowa Academy of Science
© Copyright 1931 by the Iowa Academy of Science, Inc.
Thompson, George E.
"Effect of Air Pressure on the Vibration of Quartz Crystals,"
Proceedings of the Iowa Academy of Science, 38(1), 215-215.
Available at: https://scholarworks.uni.edu/pias/vol38/iss1/60