Lowrance electronic HDS-7, HDS-5 manual 116

Troubleshooting

bubbles. (See the Installation Section for how to install the transducer.)

3.When attaching a transducer to the inside of a hull, ONLY use epoxy available from LEI (see inside back cover for or- der information).

4.Do NOT use RTV silicone rubber adhesive or any other type of epoxy. The LEI epoxy is specially formulated so that it will cure properly for shoot-through applications.

5.Clean the face of the transducer. Oil, dirt and fuel can cause a film to form on the transducer, reducing its effectiveness.

6.Electrical noise from the boat’s motor or trolling motor can interfere with the sonar. This causes the sonar to automati- cally increase its discrimination or noise rejection feature. This can cause the unit to eliminate weaker signals such as fish and can display lines across the screen.

7.The water may be deeper than the sonar’s ability to find the bottom. If the sonar can’t find the bottom signal while it’s in the automatic mode, the digital sonar display will flash con- tinuously. It may change the range to limits far greater than the water you are in. If this happens, place the unit in the manual mode, then change the range to a realistic one, (for example, 0-100 feet) and increase the sensitivity. As you move into shallower water, a bottom signal should appear.

8.Check the battery voltage. If the voltage drops, the unit’s transmitter power also drops, reducing its ability to find the bottom or targets.

Bottom echo disappears at high speeds, erratic reading or weak bottom echo while boat is moving

1.This is likely due to cavitation (turbulence) in the water sur- rounding the transducer. You may need to move the trans- ducer lower in the water or to another location. The trans- ducer cannot send or receive signals through air bubbles.

2.Electrical noise from the boat’s motor or trolling motor can interfere with the sonar. This causes the sonar to automatically increase its discrimination or noise rejection feature. This can cause the unit to eliminate weaker signals such as fish or even structures from the display. Try using resistor spark plugs or routing the sonar unit’s power and

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