Furuno CH-270 Operator's Manual page 67

4. Press ◄ or ► to adjust TVG distance, considering sea conditions. The larger the figure
the greater the distance at which the TVG works.
TVG
Distance 0
Setting
Meters 3
Feet 10
Passi/braza 2
Fathoms
２
5. Press ▲ or ▼ to close the dialog box and return to the VERT menu.
6. To suppress reflections from the sea surface or plankton, choose TVG LEVEL and then
press ►.
7. Press ◄ or ► to adjust TVG LEVEL, considering sea conditions. The larger the figure
the less the gain over distance.
8. Press the [MENU] key to register your selection and close the menu.
Wrong
0.5 1.0 1.5 2.0
8 20 40 60
30 70 130 210
5 10 20 40
5 10 20 40
Correct
Examples of proper and improper TVG
3. VERTICAL SCAN MODE
2.5 3.0 3.5 4.0
100 130 160 200
330 410 520 660
60 80 100 120
60 80 100 110
Level too high
4.5 5.0 . . . . 10.0
250 320 . . . . 1000
820 1040 3280
150 180 600
140 170 550
Distance too high
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