Installation manual

Final tests and measurements
157
851-164510 / Rev.E
8 Enter the measured hydrophone voltage U(p-p) into the
Measurement and calculation results table, and calculate
the U Hydr voltage in the same table.
→ Refer to table 6.
Measurements/calculations Value Unit Example
Noise level dB --25.2
Hydrophone voltage U(p--p) volt 0.8
U(RMS) = U(p--p)/2√2 volt 0.28
U Hydr = 20 log U(RMS) dB//1V --10.9
Table 6 Measurement and calculation results
9 Make the requisite calculations in the Measurement and
calculation results table, and enter the result into the
Receiving voltage response (VR) table.
→ The Receiving voltage re sponse (VR) table is shown as
table 7.
10 Retrieve the Hydrophone sensitivity as transmitter S
from the Test hydrophone data table.
→ The Test hydrophone data table is shown as table 3 on
page 151 (Source level measurements).
11 Enter the data into the Receiving voltage response (VR)
table.
12 Retrieve the 20 log r value from the Measurements
results table.
→ The Measurements results table is shown as table 4 on
page 154 (Source level measurements).
13 Enter the data into the Receiving voltage response (VR)
table.
VR = ÷(S + U Hydr ÷ 20 log r)
Data Value Unit Example
S = S Hydrophone
dB//µPa/V
119.2
U Hydrophone dB//1V --10.9
20 log r dB 17.5
VR (Voltage Response)
dB//1V/µPa
--90.8
Table 7 Receiving voltage response (VR)
14 Calculate the voltage response with the formula given in
Receiving voltage response (VR) table.
Expected receiving voltage response is approximately:
• VR = -90 ±3 dB//1V/µPa