Lowrance lms-522c igps 操作ガイド

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The Keel Offset feature eliminates the need for the navigator to men-

tally calculate how much water is under his keel. 
Keel Offset lets you calibrate the digital depth, chart depth scale, chart 

cursor depth and fish symbol depth displayed on the screen. To calibrate 

the depth indicators, first measure the distance from the face of the 

transducer to the lowest part of the boat. In this example, we will use 3.5 
feet. This will entered as a negative 3.5 feet, which makes the depth indi-

cators perform as if the transducer's lower in the water than it really is. 
1. Press 

|

|

↓ to Sonar Setup 

. Use 

↓ to select 

|

. 

2. The Keel Offset dialog box appears. Press 

↓ to change the plus (+) 

sign to a minus (–) sign. 
3. Press 

→ to the first number, then press ↑ to  change the number to 3 

4. Press 

→ to the second number, then press ↑ to change the number to  

5, then press 

. The depth indicators now accurately show the depth 

of water beneath the keel. 
NOTE: 

If knowing the exact depth of water beneath the keel is less impor-

tant, you can calibrate the depth indicators so that they show the ac-

tual water depth from surface to bottom. To do this, first measure the 

distance from the face of the transducer up to the surface (the water 

line on the boat). In this example, we will use 1.5 feet. This will be en-
tered as a positive 1.5 feet, which makes the depth indicators perform 

as if the transducer's higher in the water than it really is. 

1. Press 

|

|

↓ to Sonar Setup 

. Use 

↓ to select 

|

. 

2. The Keel Offset dialog box appears with a plus (+) sign at the 

front of the box. 
3. Press 

→ to the first number, then press ↑ to  change the number 

to 1. 
4. Press 

→ to the second number, them press ↑ to change the num-

ber to 5, then press 

. The depth indicators now accurately show 

the water depth from surface to bottom. 

The sensitivity controls the ability of the unit to pick up echoes. Sensi-

tivity can be adjusted, because water conditions vary greatly. A low 

sensitivity level (from zero to 50 percent) excludes much of the bottom 

information, fish signals, and other target information.