Furuno CH-250 SONAR User Manual


 
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2.11 Adjusting the Picture
2.11.1 Suppressing bottom and surface reflections
In shallow fishing grounds, excessive sea surface and bottom reflections often interfere with
wanted fish echoes and they cannot be eliminated sufficiently with the TVG controls. In such
cases, try to reduce the output power, without turning down the gain. The picture becomes
clearer when output power is reduced rather than when the gain is decreased.
1. Press the [MENU] key to open the menu.
2. Press
to select MENU and then press to select the COM1 menu.
TX POWER MAX
PULSELENGTH LONG
TX RATE 10
INT REJECT OFF
AGC OFF
: SELECT
: CHANGE MENU: END
MENU
COM1 HORZ VERT ES PRESET SYSCOM2
AUDIO LEVEL 0
Figure 2-13 COM1 menu
3. Press
or to select TX POWER and press . The following dialog box appears.
TX POWER
MAX MIN
4. Press
to select MIN. (For long range detection be sure to return the setting to MAX.)
5. Press the [MENU] key to register your selection and close the menu.