Furuno CH-270 - Manual (Page 67)

3. VERTICAL SCAN MODE
3-13
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
Setting
0 0.5 1.0 1.5 2.0 2.5 3.0 3.5 4.0 4.5 5.0 . . . . 10.0
Meters 3 8 20 40 60 100 130 160 200 250 320 . . . . 1000
Feet 10 30 70 130 210 330 410 520 660 820 1040 3280
Passi/braza 2 5 10 20 40 60 80 100 120 150 180 600
Fathoms 5 10 20 40 60 80 100 110 140 170 550
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 Correct Level too high Distance too high
Examples of proper and improper TVG