Installation manual

Introduction
In addition to the Omni picture, the vertical slice is especially
useful for visualizing the vertical distribution of a school of
fish. In that way, i t is not necessary to go over the target to see
the distribution on the echo sounder, which often results in a
spreading of the school.
Stabilization system
When the beam stabilizer is activated, both horizontal and
vertical beams will be stabilized electronically for roll and pitch
movements up to ±20 degrees. The beam direction will then
change continuously according to the vessel’s movements, and
secure an optimal contact with the targets even in rough seas.
Figure 5 Stabilization system
Reception
A great effort has been made to reduce unwanted noise to get a
clean and stable echo presentation. To achieve this goal the sonar
receiver has the following filtering possibilities:
• FM Correlation filter
• Frequency selection (Option)
• RCG (Reverberation Controlled Gain)
• PP Filter
• TVG (Time Variable Gain)
FM Correlation filter
In addition to the traditional single frequency transmitting
method, the Simrad SH80 Fish finding sonar is equipped with
an FM correlation mode.
In FM mode each transmission pulse contains up to four different
frequencies, and the receiver makes a spectrum analysis and
compares the received echoes with the transmitted frequency
code. This provides a filtering effect, which efficiently reduces
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