Operation Manual

References
209
850-165186 / Rev.B
Sensor filter: The PI54 is designed to quickly update data.
After the sensors have been submerged, the receiver requires
only three consecutive pings from individual sensors to calculate
and display their respective information. However, if you
experience problems with the reception, you may also try this
filter: it will average the data received from the sensors. Light
filtering will average the data received by the last four pings,
while heavy filtering averages the data received by the last eight
pings. We recommend that you only use heavy filtering if there
are large f luctuations in the displayed data, or if the rate of
change is small. Reduced filtering shortens the delay between
updating the changes in sensor location and the corresponding
displayed information. Default setting is L IGHT.
Catch/Bottom Sensor filter: This f ilter is used to smooth out
the information from the Catch and Bottom Contact sensors.
When the filter is switched off any change in sensor status will
immediately be shown on the display. Set to LIGHT the change
in status must last and remain stable for at least two pings before
the display is changed. When HEAVY filtering is applied the
change in status must last and remain stable for at least four
pings before the change is shown on the PI54 display.
AGC (Automatic Gain Control): This function allows the PI54
to automatically control the receiver gain. The units reads and
interprets the received signal strength, and adjusts the gain
accordingly. During normal operation, ON is the recommended
(and default) setting.
Manual gain: If you decide to switch the AGC off you must set
the gain manually. This can be useful when you work at
maximum detection ranges with favourable noise levels. The
default setting is 0 dB, and you can adjust the gain in steps of
20 dB.
Multipath filter (MP filter): When you operate in an areas with
substantial reverberation due to bottom topography, or in
shallow waters, you may experi ence problems when consecutive
operating channels have been configured, but the corresponding
sensors are not in use. False signals and sporadic error values
can also be caused by other types of hydroacoustical equipment
operating on the PI54 frequency range. This filter has been
implemented to remedy for such interference problem. Default
setting is OFF.
Multipath filter level (MP filter level): When the Multipath
filter has been enabled, you can adjust the filter level in small
steps to correct the interference problem. L ower filter values
represent stronger filtering. It is best to experiment with this
parameter by reducing the value in steps of 3 dB until the