User manual LOWRANCE LMS-525C DF

[. . . ] 988-0151-461 LMS-520C & LMS-525C DF Fish-finding Sonar & Mapping GPS Installation and Operation Instructions Copyright © 2006 Lowrance Electronics, Inc. All rights reserved. No part of this manual may be copied, reproduced, republished, transmitted or distributed for any purpose, without prior written consent of Lowrance. Any unauthorized commercial distribution of this manual is strictly prohibited. Fishing Hot Spots® is a registered trademark of Fishing Hot Spots Inc. [. . . ] This can cause the unit to eliminate weaker signals such as fish or even structure from the display. 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 continuously. 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. 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 or erratic digital reading or weak bottom echo while boat is moving 1. It must be mounted in a smooth flow of water in order for the sonar to work at all boat speeds. Air bubbles in the water disrupt the sonar signals, interfering with its ability to find the bottom or other targets. Electrical noise from the boat's 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 structure from the display. Try using resistor spark plugs or routing the sonar unit's power and transducer cables away from other electrical wiring on the boat. In order for the unit to display a fish arch, it has to be able to receive the fish's echo from the time it enters the cone until it leaves. If the sensitivity is not high enough, the unit shows the fish only when it is in the center of the cone. It is much easier to display fish arches when zoomed in on a small range of water than a large one. For example, you will have much better luck seeing fish arches with a 30 to 60 foot range than a 0 to 60 foot range. This enlarges the targets, allowing the display to show much more detail. If the boat is motionless, fish stay in the cone, showing on the screen as straight horizontal lines. This usually appears on the sonar's display as random patterns of dots or lines. 102 In severe cases, it can completely cover the screen with black dots, or cause the unit to operate erratically, or not at all. To eliminate or minimize the effects of electrical noise, first try to determine the cause. [. . . ] If you're in the United States and you have technical, return or repair questions, please contact the Factory Customer Service Department. Before any product can be returned, you must call customer service to determine if a return is necessary. Many times, customer service can resolve your problem over the phone without sending your product to the factory. Central Standard Time, M-F 800-324-1356 Lowrance Electronics may find it necessary to change or end our shipping policies, regulations, and special offers at any time. [. . . ]