Advanced Navigator Functions

Split Frequency – The transducer can operate in both 50 kHz and 200 kHz frequencies at the same time. If you choose split frequency operation, the scrolling bottom display is split horizontally; the upper half shows the 200 kHz detailed view and the lower half shows the 50 kHz image. You can also choose the split frequency display with the Fishfinder display options: Bottom Lock, A-Scope, or Zoom.

To change the frequency:

1.From the Functionbar’s top-level menu, click Frequency.

2.Click 50 KHz, 200 KHz or Split. The scrolling bottom is displayed in the selected frequency. If you choose split, the scrolling bottom is dis-played in both frequencies with 200 kHz in the upper and 50 kHz in the lower window.

3.If necessary, click Frequency/Auto to toggle between automatic and manual frequency selection.

4.Click ENTER, CLEAR, or BACK to return to the top-level Functionbar menu.

Adjusting Display Gain (Sensitivity)

The Gain, or sensitivity, of the display adjusts background noise by varying echo strength for display. The value of the GAIN control determines the strength above which echoes are displayed: If the Gain is low only the strongest echoes are displayed; as the gain is increased more, but weaker echoes (from, say air bubbles) are displayed.

The display Gain should be set high enough to see fish and bottom detail, but without too much background noise. Generally, a high gain is used in deep/clear water; a low gain in shallow/murky water.

The Fishfinder provides automatic or manual Gain adjustment. Automatic adjustment is based on depth and water conditions. As conditions change the auto-gain adjusts to display fish with a minimum of background noise. You can manually add a bias to the auto-gain setting. If you select manual adjustment, you will need to re-adjust the Gain as conditions change.

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Raymarine Marine GPS System manual Adjusting Display Gain Sensitivity, To change the frequency