User manual GARMIN GPSMAP 238 SOUNDER

[. . . ] GPSMAP 188/188C/238 Sounder chartplotting receiver & depth-finder owner's manual and reference guide (GPSMAP 188C Shown) © Copyright 2003 Garmin Ltd. 913/397. 8200 or 800/800. 1020 Fax 913/397. 8282 Garmin (Europe) Ltd. Unit 5, The Quadrangle, Abbey Park Industrial Estate, Romsey SO51 9DL, U. K. Except as expressly provided herein, no part of this manual may be reproduced, copied, transmitted, disseminated, downloaded or stored in any storage medium, for any purpose without prior written consent of Garmin. [. . . ] On the `Save Back Through' window, highlight the desired time, date, or `Entire Log' and press ENTER. Next, the track will begin saving and then display the `Saved Track' window when done. The default name, distance and number of points (500 max) will be displayed. To change the name of the saved track, highlight the name field and press ENTER, make your changes and press ENTER again. To choose a style (monochrome units) or color (color models) that will be used to display the saved track line, highlight the field and press ENTER, choose a Color or Style and press ENTER again. To display the track on the Map and Highway pages, highlight the check box to the left of `Show on Map and Highway' and press ENTER. To view the track on the map, highlight `Review on Map' and press ENTER. Highlight `OK' and press ENTER to save the track. Reference TracBack Navigation Default Track name Total Distance Change color or style of track line Check this box to display track Total number of points To activate a TracBack using the NAV key: 1. Press the NAV key, then highlight the `Follow Track' option and press ENTER. Choose either `Original', which will navigate you from the start to the end of your trip, or `Reverse', which will navigate you from the end to the start of your trip and press ENTER. Once a TracBack has been activated, the GPSMAP 188/188C/238 Sounder will take the track log currently stored in memory and divide it into segments called `legs'. Up to 254 temporary `turns' (BEGIN, TURN 1, TURN 2, TURN 3, . . . . , TURN X, END) will be created to mark the most significant features of the track log in order to duplicate your exact path as closely as possible. To get the most out of the TracBack feature, remember the following tips: · Always clear the track log at the point that you want to go back to (dock, etc. ). · The `Record Mode' option on the track log setup page must be set to `Fill' or `Wrap'. · There must be at least two track log points stored in memory to create a TracBack route. You must first save a track before using the `Follow Track' option. If there are no saved tracks, the message "There are no saved Tracks to follow" appears after you select `Follow Track. ' 55 Reference TracBack Navigation/ MOB: Man OverBoard · If the track log interval is set to the `Time' option, the route may not follow your exact path (keep the interval set to `resolution' for best performance). · If the receiver is turned off or satellite coverage is lost during your trip, the TracBack will draw a straight line between any point where coverage was lost and where it resumed. · If your track log's changes in distance and direction are too complex, 254 waypoints may not mark your path accurately. The receiver then assigns the 254 waypoints to the most significant points of your track, and simplifies segments with fewer changes in direction. Press the NAV key, highlight `Stop Navigation' and press ENTER. The MOB function allows you to quickly activate a course back to a location. For more information on setting up the Track options and saved tracks, see pages 75-76. MOB Key The GPSMAP 188/188C/238 Sounder's Man OverBoard function (MOB) lets you simultaneously mark and set a course to a position for quick response to emergency situations. To activate the MOB function: 1. Press ENTER to confirm and begin navigating to the MOB position. Highlight `Stop Navigation' and press ENTER to stop navigating. Once a MOB has been activated, a `MOB' waypoint with an international MOB symbol is created and the unit is set on an active navigation to that point. The MOB waypoint is stored in the waypoint list and may be deleted like any other waypoint (see page 50). To stop navigation to the MOB position: 1. Press the NAV key, highlight `Stop Navigation' and press ENTER. 56 Creating a Route Reference Creating a Route The last way to navigate to a destination is to create a user-defined route. [. . . ] On both graphs it appears the fish and tree are side by side as shown in Example 1. However, when we look at Example 2, we see that the fish can be several feet from the tree. It is important to remember that the sonar cannot determine where in the coverage area the tree or fish are, only that the returns were received at the indicated depths in the same time frame. Appendix I Understanding the Chart Enlarged Transducer View Branches Enlarged Transducer View Branches Fish Remember that the sonar displays a 2-D picture of the underwater environment. The fish and tree could be located anywhere in the coverage area at that time. Fish 113 Example 1. [. . . ]