Garmin CR 1522, Owner'S Manual

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CHAPTER 2 GETTING STARTED 32
2.3.2 Adjusting the Range and Zoom
The range of the radar signal indicates the length of the pulsed signal transmitted and
received by the radar. As the range increases, the radar transmits longer pulses in order
to reach distant targets. Closer targets, especially rain and waves, also reflect the longer
pulses, which can add noise to the radar screen. You can also zoom in and out to adjust
the visible range on the radar screen.
1 Before pressing any other buttons, press [SELECT] to switch the main knob control
between Range and Zoom .
TIP: Press [BACK] to cancel a selection.
2 Rotate the main knob to adjust the range or the zoom. The range determines the
intervals between the range rings, which are concentric circles on the radar display.
The range and the range ring interval are shown at the top-left corner of the radar
display. The range is marked by the bearing ring (the range ring with markings).
TIP: Adjust to a shorter range to navigate through crowded water, and increase the range
when you move out to open water to prevent possible collisions.
2.3.3 Hiding the Heading Line
The heading line may obscure a target ahead of your boat. To temporarily hide the
heading line, press and hold [HL OFF] .
The heading line and optionally the range rings and target symbols will be hidden while
the button is held. Press [MENU] > Preferences > HL Off Mode to change this.
2.4 Optimizing the Radar Display
2.4.1 Adjusting Gain
Gain controls the level of detail and noise shown on the radar display. A higher gain
amplifies the signals received and reveals smaller targets but increases noise and clutter
shown on the radar display. A gain too low will miss smaller targets while a gain too high
will obscure even larger targets.
• Rotate the [GAIN] knob to adjust the gain and reduce background noise on the screen.
• Press the [GAIN] knob to open the Gain menu. Rotate and press the knob to make a
selection.
• You can also adjust gain by pressing [MENU] > Echo Tuning > Gain .
TIP: From a high level of gain, gradually reduce gain until the noises are barely showing
on the radar display.
2.4.2 Adjusting Sea Clutter Reduction
Sea Clutter are echoes reflected off sea waves, shown on the central area of the
radar screen with random echo signals. The sea clutter reduction setting affects the
appearance of nearby signals more than it affects distant echoes. A higher sea clutter
reduction setting reduces the appearance of clutter caused by nearby waves, but it can
also reduce or eliminate the appearance of nearby targets.
• Rotate the [SEA] knob to adjust the sea clutter reduction and reduce echoes caused
by choppy sea conditions.
• Press the [SEA] knob to open the Sea Clutter menu. Rotate and press the knob to
make a selection.
• You can also adjust sea clutter by pressing [MENU] > Echo Tuning > Sea Clutter .