Wesmar SS395 Installation & Operation Manual page 7

convenience sonar range is repeated.
PULSE
Pulse refers to the transmit pulse or the time the
transmitter is on pushing sound energy into the
water. A long pulse, 100% is best for long-range
detection. Selecting shorter pulse lengths will
increase range resolution separating two targets
close together. As the pulse length is shortened,
near and far gains will need to be increased.
SECTOR
Same sector adjustment found in the last selection
screen, Wesmar 395. For convenience sector is
repeated.
TVG
Time Variable Gain offsets propagation loss as
sound energy moves through the water. A target
at long range will have a small echo than close
to the vessel. In order for this target to mark the
same color at different ranges the receive gain must
increase proportionally with range. Propagation
losses of sound energy will change with frequency,
salinity, and the amount of plankton and algae in
the water. Adjust TVG according to the frequency
of the sonar.
Adjustment:
160kHz set TVG to 400,
span 200 to 600
110kHz set TVG to 600,
span 400 to 800
60kHz set TVG to 800,
span 600 to 1000
Each 100 units will equal 250 ft or 75 meters of
range. A setting of 400 will then equal 1000 ft or
300 meters. When using the blue background a
gray ring will display on the screen equal to the
TVG setting. Targets on the inside of the ring will
be compensated for propagation losses where
targets outside the ring will become stronger as
the vessel approaches until the target cross over
the gray ring.
SPEED
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