Furuno FSV25S, Operator'S Manual, Page: 28 / 163

1. OPERATIONAL OVERVIEW
1-14
1.8 How to Adjust the Gain
The GAIN control adjusts receiver gain (sensitivity) for the horizontal and vertical
modes. Adjust it so fish echoes are clearly displayed with minimal noise on the screen.
Too high a gain setting not only displays excess noise and makes it difficult to discrim-
inate wanted echoes but also causes bottom echoes to be painted in strong colors,
resulting in echoes being masked by bottom reflections. Normally, set the control
somewhere between positions 3 and 7.
1. If the horizontal and vertical modes are active, press the H/V/S key to show the
range and gain indications of the mode you wish to adjust. Pressing the H/V/S key
changes the color of the range and gain indications to orange.
• H1/H2: Horizontal1 or horizontal2
• V1/V2: H or V display
2. Adjust the GAIN control.
New gain setting is momentarily displayed in large characters at the top of each dis-
play. The setting value is always displayed next to “G“. (For the vertical display, the
gain indication is shown at the bottom of the display.)
Note 1: The gain can also be adjusted from the gain indication. Put the cursor on the
gain indication to highlight it in yellow then roll the scrollwheel.
Note 2: The default function of the F10 key is [Gain Knob Setting], which adjusts the
gain. See page 6-4.
Gain too low
Gain proper
Gain too high
17° T
H-UP
P 8
40
50
H R 400m
G 1. 0
Put the cursor on the gain setting,
which is then highlighted in
yellow. Spin the scrollwheel to
change the setting.