Ultrasonic equipment innovator and manufacturer, Precision Acoustics Ltd,
has expanded its pressure measurement range with new 2 mm and 4 mm
diameter needle hydrophones that have been designed to provide much
higher sensitivity at frequencies below 1 MHz.
Although primarily aimed at applications such as underwater acoustics and
characterisation of low frequency transducers, the new probes also suit
frequencies above 1 MHz where very weak signals need to be measured.
The frequency range is sufficiently broad that the new 4mm hydrophone has
been calibrated from 30 kHz to 40 MHz by NPL (London)
The new needle hydrophones are designed to be used with the HP
Submersible preamplifier that provides immediate signal buffering and acts
as a precision 50 Ohm source for Precision Acoustics’ high performance
hydrophone system. The larger active areas of these devices provides much
greater sensitivity (7V/MPa for the 4mm probe, 2.5 V/MPa for the 2mm
As a result these new devices have a lower noise equivalent pressure than
the existing range of plug-in interchangeable probes that have diameters
from 40 microns to 1 mm. These hydrophones can also be used conjunction
with the A20 in-line attenuator to permit the measurement of higher
amplitude signal whilst minimising the risk of preamplifier overload.
Precision Acoustics also manufacture a wide range of membrane and fibre
optic hydrophones as well as ultrasonic transducers, scanning tanks and
other acoustic measurement products that are exported worldwide.