IEC 62127-2:2007/COR1:2008

IEC 62127-2
(First edition – 2007)
Ultrasonics – Hydrophones –
Part 2: Calibration for ultrasonic fields up to 40 MHz

CORRIGENDUM 1
Page 15
5 Overview of calibration procedures
5.1 Principles
On page 16, instead of:
NOTE 2 “Absolute” hydrophone calibration is understood here in the sense of “without reference to another
hydrophone”. This is sometimes also referred to as “primary” or “substitution” procedure, which means a
sensitivity comparison with a calibrated reference hydrophone. The reference hydrophone itself may have been
calibrated in “absolute” terms or against another reference hydrophone, and so on. Obviously, there are two
different, fundamental procedures: to perform an absolute hydrophone calibration and to compare the sensitivity
of two hydrophones. Clauses 9, 10, 11, Annexes D, F and H deal with the former procedure. The latter procedure
is dealt with in detail in Clause 12. It should be noted that a substitution calibration usually involves both steps and
that the interested user should refer to both Clause 12 and other clauses dealing with absolute calibration (and that
uncertainties from both fundamental steps contribute to the final calibration uncertainty in the case of a
substitution calibration).
read:
NOTE 2 “Absolute” hydrophone calibration is understood here in the sense of “without reference to another
hydrophone”. This is sometimes also referred to as “primary” calibration. On the other hand, hydrophones are
often calibrated in practice following a “secondary” or “substitution” procedure, which means a sensitivity
comparison with a calibrated reference hydrophone. The reference hydrophone itself may have been calibrated in
“absolute” terms or against another reference hydrophone, and so on. Obviously, there are two different
fundamental procedures: to perform an absolute hydrophone calibration and to compare the sensitivity of two
hydrophones. Clauses 9, 10, 11, and Annexes D, F and H deal with the former procedure. The latter procedure is
dealt with in detail in Clause 12. It should be noted that a substitution calibration usually involves both steps and
that the interested user should refer to both Clause 12 and the other clauses dealing with absolute calibration (and
that uncertainties from both fundamental steps contribute to the final calibration uncertainty in the case of a
substitution calibration).
Page 20
6.3 Hydrophone size
In the second sentence, instead of:
“.the effective radius of the hydrophone small be small compared with.”
read:
“the effective radius of the hydrophone shall be small compared with.”
August 2008
Page 25
10 Free field calibration by planar scanning
On page 26, for Equation (6), instead of:
P( (l) = I(x,y,l,t) cos Θ dy dz 6)
∫∫
read:
P(l) = I(x, y,l,t) cos Θ dy dx (6)
∫∫
Page 38
Annex D Absolute calibration of hydrophones using the planar scanning
technique
D.2 Hydrophone scanning methodology
For Equation (D.2), instead of
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