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Wireless Temperature Measurement of a Sample in Vacuum

  • G. Richard Blair
Conference paper

Abstract

The temperature of a sample suspended from a microbalance is difficult to measure without interfering with the weighing process. A device is described in which the sample temperature causes a change in frequency of the infrared emitted from a gallium arsenide photodiode. The oscillator unit is mounted in a small hermetically sealed box which in turn is moiunted on the microbalance as part of the sample weight. A thermistor is buried in the sample, attached by fine wires at any convenient distance from the box to minimize circuit thermal sensitivity. Power to operate the oscillator is derived from a silicon solar cell, activated by a light exterior to the chamber. The gallium arsenide cell output can be detected at distances ranging from a few inches to several hundred feet by a suitable photocell. The detected signal is fed into a frequency meter.

Experimental data for frequency change vs. temperature are shown. A range of 400 C is easily attained. The accuracy of temperature measurement is ±0.15%.

Keywords

Solar Cell Sample Temperature Gallium Arsenide Silicon Solar Cell Furnace Wall 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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References

  1. 1.
    A. W. Czanderna, Ultramicrobalance review, in: S. P. Wolsky and E. J. Zdanuk (eds.), Ultra Micro Weight Determination in Controlled Environment, Inter science. New York (1969), p. 37.Google Scholar
  2. 2.
    D. Hilleicke and P. Schmider, in: C. Massen and H. Van Bechum (eds.). Vacuum Microbalance Techniques, Vol. 7, Plenum Press, New York (1970) (in press).Google Scholar
  3. 3.
    Alan J. Adler, Wireless temperature measurement with radio telemetry, Sixth Conference and Exhibit, Temperature Measurement Society, April 21, 22, 1969, Hawthorne, California.Google Scholar
  4. 4.
    General Electric Engineering Data Sheet 6200, “Manmade diamond thermistors.”Google Scholar
  5. 5.
    Ernest G. Wolff, Oxide thermistor for use to 2500 K, Rev. Sci. Instr., 40, 544 (1969).CrossRefGoogle Scholar

Copyright information

© Plenum Press, New York 1971

Authors and Affiliations

  • G. Richard Blair
    • 1
  1. 1.Hughes Aircraft Company Electron Dynamics DivisionTorranceUSA

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