Furuno GP-1870F, Руководство оператора

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7. FISH FINDER OPERATIONS
7-13
7.11 How to Measure Depth, Time Between Locations
You can measure the depth to an object with the VRM. Also, you can measure the time
from the right edge to a location. For example, you can measure how many minutes
ago the echo appeared.
To measure the depth, press the up and down arrow pads on the CursorPad to put
the VRM on the object to measure the depth. To measure time, press the right and left
arrow pads on the
CursorPad .
The VRM cannot be operated when the Gain adjustment window is active.
7.12 How to Balance Echo Strength
A school of fish at a depth deeper than a school of equal strength in shallow water ap-
pears in weaker colors. This condition is caused by the attenuation of the ultrasonic
wave. To display the schools of fish in the same colors, use the TVG. The TVG auto-
matically adjusts the gain with depth so that echoes of the same strength and different
depths are shown in the same colors.
Do the following to balance echo strength:
1. Open the [FISH FINDER] menu then select [FISH FINDER SETUP].
2. Select [50 kHz TVG] or [200 kHz TVG].
3. Enter TVG value. Lower the TVG setting to decrease the gain for near distance.
4. Press the
ESC/MENU key to close the menu.
VRM depth
0 0
10 10 10
20 20 20
30 30 30
0’07”
14.2
Time elapsed
Unwanted echoes
from surface Unwanted echoes
are erased.
Echoes of the same size
are displayed in different
sizes and colors
depending on depth. Echoes of the same size
are displayed in same
sizes and colors.
0 ft
300 ft
300 ft
0 ft