User manual HUMMINBIRD 250DX

[. . . ] Operations Manual THANK YOU Thank you for choosing Humminbird, America's #1 name in fishfinders. Humminbird has built its reputation by designing and manufacturing top-quality, thoroughly reliable marine equipment. Your Humminbird is designed for trouble-free use in even the harshest marine environment. In the unlikely event that your Humminbird does require repairs, we offer an exclusive Service Guarantee - free of charge during the first year after purchase, and available at a reasonable rate after the one-year period. [. . . ] If the 20m (60') or 40m (120' ) range is in Upper Zoom Limit use, the Zoom range is 5m (15'), if a 60150m (180'-480') depth range is in use, the Zoom range is 10m (30'), and if the 185m (600') range is in use, the Zoom range is 20m (60'). The Zoom range is shown on the left side of the screen and full range information is shown on the right side of the display. Zoom can either operate automatically, in which the Zoom range is constantly adjusted to show the bottom, or manually, in which the user controls the location of the Zoom range. 16 Lower Zoom Limit USING THE 250DX MENU FUNCTIONS Automatic Zoom is especially helpful when looking for structure or bottom detail. The Automatic Zoom keeps the bottom in view even in quickly changing terrain, but is most useful in flatter areas without considerable depth variation. Manual Zoom provides detailed information of any area from the surface to the bottom. In manual Zoom, the Zoom range does not move as the terrain changes. When the range is shown in the menu, the upper number represents the top of the current Zoom range. The lower number represents the bottom of the Zoom range. Use the UP and DOWN ARROW buttons to move this range. The upper number can never be less than 0 (the surface of the water), and the lower number can never be greater than the active depth range. The difference between the two numbers (the Zoom range) is preset and determined by the active depth range. Once manual Zoom is selected, the display appears the same as in Auto Zoom, but the zoom range does not change automatically. To disable Zoom, press the MENU button until the Zoom menu is on-screen. Use the UP ARROW to highlight Off, and let the menu time out. When the unit is powered off, the Zoom menu returns to Zoom Off. The 250DX contains an audible alarm to warn you of shallow water depths. The alarm is adjustable to depths of 1m (3') to 30m (99'). When the alarm is enabled, an audible alarm sounds if the water beneath the boat is equal to or less than the selected alarm depth. The alarm sounds continuously for about five seconds, and then intermittently to remind you that you are still in shallow water. 17 USING THE 250DX MENU FUNCTIONS Fish Alarm. The Fish Alarm alerts you to the presence of fish, or other targets not connected to the bottom. The Fish Alarm has three different settings that correspond to the three different size fish symbols shown on-screen. The default setting is "OFF. " With the "Large fish only" setting, the 250DX alarms on only those targets that are represented by the large fish symbols. [. . . ] It may take several tries to optimize high speed operation. This can also be a result of air or turbulence in the transducer location caused by rivets, ribs, etc. 28 MAINTENANCE TROUBLESHOOTING 7. Your 250DX has over-voltage protection that turns the unit off when input voltage exceeds 20 VDC. Some outboard motors do not effectively regulate the power output of the engine's alternator and can produce voltage in excess of 20 volts when running at high RPMs. [. . . ]