| Autor: |
George L. Boyer, Paul Tamarkin, Robert T. Beyer |
| Rok vydání: |
1951 |
| Předmět: |
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| Zdroj: |
The Journal of the Acoustical Society of America. 23:7-11 |
| ISSN: |
0001-4966 |
| DOI: |
10.1121/1.1906733 |
| Popis: |
When acoustic signals are detected by a microphone, an electric signal is also picked up. The latter produces a spatial modulation of the acoustic signal. This effect was used by Labaw to make a point by point determination of a progressive acoustic wave front in water. The effect is analyzed in this paper and an electronic device is described which reduces the time required for measuring the wave fronts to about one third that previously needed. The device employs a phase discriminator which compares the phase of the electric and acoustic signals at a given point. Since the phase of the electric signal is sensibly constant throughout the tank, this signal is used as a reference level. An output current is obtained which is proportional to the phase difference of the two signals. Measurements are then made by locating points with zero current output. Typical experimental measurements are given. |
| Databáze: |
OpenAIRE |
| Externí odkaz: |
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