Raymarine RL70C, Owner'S Handbook Manual

Page: 72 / 218

58 HSB Series LCD Display
2. Press GAIN or MULTI . The slider soft keys are displayed. The last-used
slider is highlighted (displayed in inverse video) to show that it is selected.
3. Press the required soft key so that the slider box is highlighted.
The
TUNE
and
GAIN
soft keys toggle the control between Auto and Manual
mode. The SEA soft key toggles the control between Auto-Harbour, Auto-
Offshore and Manual mode. If you select Manual mode the last auto setting
is retained. You can only move the slider if the control is set to Manual.
4. Use the trackpad to move the slider up or down. You can press and hold the
control to move the slider quickly rather than in single steps.
The image on the screen changes as you move the slider, so that you can see
the effect of your adjustment.
The tuning slider displayed in Manual mode shows the current received
signal strength, in 8 steps. Adjust the slider to obtain the maximum reading
on the indicator.
Note: Because the changes to the settings are made immediately, you cannot
revert to the previous setting by pressing
CLEAR
.
5. When you have set all the controls to the levels you require, press ENTER ,
or
CLEAR
to clear the slider display. The status bar is updated to indicate
which controls are switched to Auto or On.
Gain Control and Sea Control
The
GAIN
control can be set to either Auto or Manual. In Auto mode, the
Pathfinder radar optimises the setting. The SEA control can be set to Auto-
Harbour (default), Auto-Offshore or Manual mode. In Auto-Offshore mode, the
Pathfinder Radar optimises its settings to account for the effects of sea clutter.
In harbours or close proximity to land different auto settings may be
necessary to cater for the effects of land clutter. To avoid losing small
targets it is therefore advisable to set the Sea control to Auto-Harbour
mode. Alternatively, set both Sea and Gain to Manual mode then adjust
the settings to ensure that all close small targets are visible.
The GAIN control adjusts the level of the display of signals received from the
scanner; it is equivalent to a volume control on a radio.
Because the
SEA
control affects the gain, you may need to manually readjust it if
you manually change the Gain setting.
Gain Control
When the Gain control is set to Manual, you should check it every time you
change the range scale.
On long range settings, the gain should be set to give a slight speckle in the
background of the radar picture. Do not set the gain too low, or you may miss
small or weak targets.
Adjusting Gain,
Sea Clutter and
Rain Clutter
MANUAL
GAIN
50%