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Hydrophone Handbook

      Frequently Asked Questions

 Can total acoustic power be measured with hydrophone? How
 does it compare with measurements from an RFB?
 Yes, but a scanning system is required in order to perform a
 planar scan and then integrate the intensity over the plane.
 Typical uncertainties measuring total acoustic power with the
 hydrophone are typically more than 25%, whereas with the RFB
 they are typically less than 10% and can be as low as 5% for
 unfocused transducers.
 Making total acoustic power measurements with an RFB offers
 a significant throughput advantage.
 Can Onda hydrophones be used as a source or transmitter?
 Yes, but it has not been established on how hard each
 hydrophone can be driven without damage. Because the
 intended design for Onda’s hydrophones are to “receive”, the
 damage threshold will be highly variable from one device to the
 next.
 What is the difference between calibrations at Onda compared
 with a calibration at a National Laboratory?
 A primary advantage with sending devices to Onda for
 calibration is that they can be inspected against manufacturing
 QC criteria. For all re-calibrations, Onda includes a free
 evaluation of any Onda hydrophone before commencing with
 the calibration. If a hydrophone issue is discovered, Onda will
 inform our customers and present the option to forego the
 costly calibration.
 Over what frequency range do you calibrate your
 hydrophones?
 Onda has the capability to support acoustic calibrations from 30
 kHz up to 60 MHz. Please refer to the Ordering Details section
 for a list of calibration options.

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