How To Select The Range Scale; How To Adjust The Gain (Sensitivity) - Furuno 1815 Operator's Manual

5. OPERATION
5.8

How to Select the Range Scale

The selected range scale, range ring interval and pulse length are shown at the top
left corner on the screen. When an objective target comes closer, reduce the range
scale so that a target appears in 50-90% of the display radius.
Rotate the RANGE knob to select range, clockwise to increase the range, or counter-
clockwise to decrease the range.
5.9

How to Adjust the Gain (sensitivity)

The gain functions to adjust the sensitivity of the receiver for the best reception. The
gain can be adjusted automatically or manually.
1. Press the RANGE knob to show the [GAIN/SEA/RAIN] window.
2. The cursor is selecting [GAIN]. Press the ENTER key to show [GAIN AUTO] or
[GAIN MAN] as required. For manual adjustment, see the section below.
3. Press the MENU/ESC key to close the window.
Manual adjustment of gain
1. Rotate the RANGE knob (or use  or  on the Cursorpad) to adjust the gain so
that weak noise appears on all of the screen. If the gain is too low, weak echoes
are erased. If the gain is too high, the background noise hides weak targets.
2. Press the MENU/ESC key to close the window.
5-10
AUTO: Automatic, MAN: Manual
GAIN/RAIN/SEA window
GAIN setting bar