Doc. P/N:
WSP-009-004
Version:
V1.3
Issue Date: August 2013
Page 25 of 62
Operator Manual
4.8.6 Power Tab
The
Power
tab reveals three Power Options:
4.8.6.1 Manual Power
This setting allows the user to choose any system power level using the Power Level on the
Menu Task Bar (See “4.5 Power Level” on page 15).
4.8.6.2 Auto Power by Depth
Auto Power by Depth displays 14 power levels, seven in the low range and seven in the high
range, that can have each level individually set from fourteen drop down boxes. A
Defaults
button sets all fourteen power levels to a default setting. When setting power level depth
settings individually, click the green
Tick
button when you have completed the settings.
Figure 20. Ship Setup Options – Power Tab
Note: Automatic Power will
only work when the Power
Indicator is Green or Blue!
Note: There are
TWO
different Automatic Power
modes. Automatic Power
by Signal
and
Automatic
Power by Depth. Automatic
Power by Signal is better for
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Absorption Loss
If a power level is set out of sequence, for example level 5 is set to 14 m, level 6 is 50 m and
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level is invalid (level 6 in our example). Level 6 can then be set individually to a level below that
of level 7 and above level 5.
Click the tick and reset Power Level 6 to a level between Power
Levels 5 and 7.
If no other power levels have been changed, clicking “Defaults” will
reset the power level.
4.8.6.3 Auto Power by Signal
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received level is set to prevent saturation of the receiver. This should provide the best overall
system performance.
4.8.6.4 Absorption Loss
As sound travels through water, some of the energy contained is absorbed by the water,
resulting in attenuation of the signal. The chosen value of absorption loss is used when
calculating backscatter. For a 160kHz WASSP system, a default value of 40dB/km is used. This
is set at time of installation and should not be changed without a clear understanding of the
absorption properties of the water in the area you are working in.
