Kongsberg Simrad ST90, Reference Manual

Page: 66 / 690

64
442704/A
b Place the cursor on the button. Press and hold the left mouse button. Move the
cursor horizontally over the button. Release the mouse button when requested
value is shown.
c Select the middle of the button to open it. If you have a keyboard connected to the
ST90 system, type the requested value.
d Select the middle of the button to open it. Select a value from the options provided.
6 Open the button and select
Apply to all
if you wish to use the chosen setting in all the
views in the current presentation mode.
Related topics
Getting started, page 34
Starting normal operation, page 52
Range function, page 420
Adjusting the echo sensitivity
Some echoes are weak while others are stronger. To compensate for this it is often necessary
to adjust the sensitivity of the ST90 system. This adjustment is commonly referred to as
gain .
Context
You can compare this gain setting with the volume control on your car radio. When the gain
is increased, the echoes will appear stronger. Weak echoes will be easier to see. However,
since you also increase the acoustic noise in the reception, the echo presentations will also
show this noise. Too much gain may therefore "distort" the presentation.
Comparing the gain function with the volume control on your car radio is not very accurate.
In fact, the gain in the ST90 system is constant. The
Gain
function is used to adjust the
sensitivity. This is done by controlling the minimum level of detection. When you increase
the gain level (more positive number), you reduce the minimum level of detection, and
thus
increase the echo sensitivity.
Simrad ST90 Reference Manual