Chart Speed. Lowrance electronic LMS-525C DF, LMS-520C

A good way to gauge your speed sensor's performance is to compare its reading with the ground speed measured by your unit's GPS functions.

When you make a run to compare GPS ground speed to speed sensor speed, perform your test in relatively calm water free of current, if possible. (Unless, of course, you are taking the speed of current into consideration when making your calculation.) After you have a correction figure, here's how to enter it:

1. Press MENU | MENU | ↓ to S

ONAR

S

ETUP

| ENT | ↓ to C

ALIBRATE

W

ATER

S

PEED

| ENT .

2. Enter the number you calculated earlier: press ↑ or ↓ to change the first character (+ or –), then press → to move the cursor to the next number and repeat until the percentage is correct, then press EXIT .

Chart Speed

The rate that echoes scroll across the screen is called the chart speed.

The default is maximum; we recommend that you leave the speed set there for virtually all fishing conditions.

You, however, might consider experimenting with chart speed when you are stationary or drifting very slowly. You may sometimes achieve better images as you slow down the chart speed to match how fast you are moving across the bottom.

If you are at anchor, ice fishing or fishing from a dock, experiment with a chart speed around 50 percent. If you are drifting slowly, try a chart speed around 75 percent. When you are stationary and a fish swims through the sonar signal cone, the image appears on the screen as a long line instead of a fish arch. Reducing the chart speed may result in a shorter line that more closely resembles a regular fish return.

Sonar Page menu with Chart Speed command selected (left).

Chart Speed Control Bar (right).

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If you do experiment with chart speed, remember to reset it to maximum when you resume trolling or moving across the water at higher speed.

To change chart speed:

1. From the Sonar Page, press MENU | ↓ to C HART S PEED

| ENT .

2. The Chart Speed Control Bar appears. Press ↓ to decrease chart speed; press ↑ to increase chart speed.

3. When it's set at the desired level, press EXIT .

Colorline ™

Colorline lets you distinguish between strong and weak echoes. It

"paints" a brighter color on targets that are stronger than a preset value. This allows you to tell the difference between a hard and soft bottom. For example, a soft, muddy or weedy bottom returns a weaker signal which is shown with a narrow, colored line (dark blue tinged with red or a little yellow.) Since fish are among the weakest echoes, they show up mostly as blue arches. A hard bottom or other relatively hard target returns a strong signal which causes a wider brightly colored line (reddish yellow to bright yellow.)

If you have two signals of equal size, one with red to yellow color and the other without, then the target with brighter color (yellow) is the stronger signal. This helps distinguish weeds from trees on the bottom, or fish from structure.

Colorline is adjustable. Experiment with your unit to find the Color-

Line setting that's best for you.

Sonar Page menu with ColorLine command selected (left).

The Colorline control bar (right).

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