GPSMAP 188/188C/238 Sounder chartplotting receiver & depth-finder (GPSMAP 188C Shown) 188Ccover.
© Copyright 2003 Garmin Ltd. or its subsidiaries Garmin International, Inc. 1200 East 151st Street, Olathe, KS 66062, U.S.A. Tel. 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. Tel. 44/1794.519944 Fax 44/1794.519222 Garmin Corporation No. 68, Jangshu 2nd Road, Shijr, Taipei County, Taiwan Tel. 886/2.2642.9199 Fax 886/2.2642.9099 All Rights Reserved.
Preface Introduction Congratulations on choosing one of the most advanced marine navigation systems available! The Garmin GPSMAP® 188/188C/238 Sounders utilize the proven performance of Garmin GPS and full featured mapping to create an unsurpassed marine navigation chartplotters. Preface and Registration This manual covers instructions for the GPSMAP 188, GPSMAP 188C (color), and GPSMAP 232. Unit operation and specifications will be the same on all three models, unless otherwise specified.
Introduction FCC Compliance FCC Compliance The GPSMAP 188/188C/238 Sounder complies with Part 15 of the FCC interference limits for Class B digital devices FOR HOME OR OFFICE USE. These limits are designed to provide more reasonable protection against harmful interference in a residential installation, and are more stringent than “outdoor” requirements.
The GPS system is operated by the United States government, which is solely responsible for its accuracy and maintenance. The system is subject to changes which could affect the accuracy and performance of all GPS equipment. Although the Garmin GPSMAP 188/188C/238 is a precision electronic NAVigation AID (NAVAID), any NAVAID can be misused or misinterpreted and, therefore, become unsafe.
Introduction Warranty and Serial Number Serial Number Use this area to record the serial number (8-digit number located on the back of the unit) in case it is lost, stolen, or needs service. Be sure to keep your original sales receipt in a safe place or attach a photocopy inside the manual. Serial Number: * * , The GPSMAP 188/188C/238 Sounder is fastened shut with screws.
Software License Agreement BY USING THE GPSMAP 188/188C/238, YOU AGREE TO BE BOUND BY THE TERMS AND CONDITIONS OF THE FOLLOWING SOFTWARE LICENSE AGREEMENT. PLEASE READ THIS AGREEMENT CAREFULLY. Introduction Software License Agreement Garmin grants you a limited license to use the software embedded in this device (the “Software”) in binary executable form in the normal operation of the product. Title, ownership rights and intellectual property rights in and to the Software remain in Garmin.
Introduction Packing List , GPSMAP 188/188C/238 Sounder Standard and Optional Transducers Unit part numbers 010-00268-01, 010-00239-02, 01000239-03, and 010-00250-11 include a 200/50kHz, 10/40 degree, plastic, depth and temp, transom mount transducer. For a complete list of optional transducers, see page 96. For the most recent list of available accessories for your GPS unit, current user manuals and software updates, visit our web site at www.garmin.com.
Designed for detailed electronic charting capability, the Garmin GPSMAP 188/188C/238 Sounder is a powerful navigation device that can give you the information you need: Introduction Precision Performance • 188C: High-contrast, 16-color LCD screen with backlighting; 188/238: High-contrast, ten-level gray, LCD screen with backlighting • 12-channel parallel receiver tracks and uses up to 12 satellites for fast, accurate positioning • WAAS Capable — receive signals from the additional set of WAAS (Wide Area A
Introduction Active Route Page . . . . . . . . . . . . . . . . . . . . . .19 Main Menu Page . . . . . . . . . . . . . . . . . . . . . . .20 Table of Contents Section Two: Reference . . . . . . . . . . . . . . . . 22-77 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . i-viii Preface and Registration . . . . . . . . . . . . . . . . . . i FCC Compliance . . . . . . . . . . . . . . . . . . . . . . .ii Warnings and Cautions . . . . . . . . . . . . . . . . . iii Warranty . . . . . . . . . . .
Using the Keypad ZOOM IN Key— adjusts the map scale to display a smaller area with more detail (Zooms in). ZOOM OUT Key— adjusts the map scale to display a larger area with less detail (Zooms out). NAV Key— displays the Go To and Follow navigation menu. PAGE Key— selects the main pages in sequence and returns display from a submenu page. QUIT Key— returns the display to the previous page and, when entering data, it restores the previous value (cancels data entry).
Getting Started Initializing the Receiver/ Power On The GPSMAP 188/188C/238 Sounder’s advanced keypad system is designed to allow for fast, convenient selection of navigation options and data entry. The Getting Started Tour will introduce you to the keypad and provide a ‘hands-on’ lesson in using the GPSMAP 188/188C/238 Sounder. We strongly encourage you to follow the Getting Started tour before using your unit for actual navigation.
To graphically initialize the GPSMAP 188/188C/238 Sounder: 1. Press the MENU key twice for the Main Menu. Press Up or Down on the ARROW KEYPAD until the ‘GPS’ tab is highlighted, then press the MENU key once. Getting Started Initializing the Receiver 2. Using the ARROW KEYPAD, highlight ‘Initialize Position’ and press ENTER to initialize the receiver from the map. The Initialize Position Page appears, prompting you to select your approximate location with the map cursor. 3.
Getting Started Selecting Options Selecting Options and Entering Data Before moving ahead into the features of the GPSMAP 188/188C/238 Sounder, you will need to learn basic operations. You can select and activate options and enter data to customize the GPSMAP 188/188C/238 Sounder to fit your requirements. You can use the ENTER/MARK key and ARROW KEYPAD to select options, enter names and numbers in data fields, and activate your selections.
Naming a waypoint or placing any sort of data that has not been predefined requires the use of both the ARROW KEYPAD and the ENTER/MARK key. Getting Started Entering Data To enter a name or number in a data field: 1. Once you have accessed a page with programmable data fields (i.e. ‘ Waypoint Edit’) you can use the ARROW KEYPAD to move the cursor (Highlight) to fields on the page. Use the UP/DOWN arrows to move up or down and the LEFT/RIGHT arrows to move sideways. 2.
Getting Started Tour/Backlighting GPSMAP 188/188C/238 Sounder Getting Started Tour The Garmin GPSMAP 188/188C/238 Sounder is a powerful electronic navigation system that provides detailed map coverage and convenient control of many advanced features right from the screen display. This tour is designed to take you through the basic pages and functions of the system using the simulator mode.
You may also adjust the screen contrast (GPSMAP 188/238 monochrome only). To adjust the screen contrast: 1. Press POWER and the Light and Contrast window appears. Getting Started Simulator Mode 2. To decrease or increase the screen contrast, press left or right on the ARROW KEYPAD. 3. Press the ENTER/MARK key to finish. Each page of the GPSMAP 188/188C/238 Sounder’s system also features an options page, which gives you access to other functions and features that relate to the specific page you are viewing.
Main Pages Getting Started Main Pages/ Map Page The Map Page is one of six main pages used in the GPSMAP 188/188C/238 Sounder’s system. The six main pages are the Map Page, Sonar Page, Compass Page, Numbers Page, Highway Page, and Active Route Page. All six pages are linked together in a simple chain, which allows you to scroll through the pages in either direction using the PAGE and QUIT keys.
Using the Map Cursor Working from the Map Page is a simple process that centers around the use of the cursor. Controlled by the ARROW KEYPAD, the cursor is an important tool that can be used to pan to other map locations, mark and edit waypoints and routes, and review position data of on-screen map items and waypoints. Getting Started Map Cursor To get a feel for using the Map Page and using the cursor, try the following exercise: 1. Use the IN/OUT keys to set the map scale to the 50 nm setting.
Getting Started Marking Waypoints To mark your present position: 1. Hold down the ENTER/MARK key until the ‘New Waypoint’ window appears then release the key. The window will show a default three-digit waypoint name/number (001), symbol (dot), and position. You can leave the name as the auto-assigned number, but for this exercise, lets change the name to ‘DOCK’. 2. Use the ARROW KEYPAD to highlight the waypoint name field (001) and press ENTER/MARK. You will see that just the first ‘0’ is now highlighted. 3.
Going to a Destination GPS is all about marking positions as waypoints and navigating to them using the receiver’s steering guidance and map displays. We’ve already seen how to use the ENTER/MARK key to store your present position, so it’s time to move on to the fun part—going to a destination. Getting Started Using the NAV Key The NAV key, located on the keypad above the QUIT key, is the primary tool used to select a destination waypoint, TracBack, or a route to navigate.
Getting Started Simulated Tour To activate the practice route stored in memory for navigation: 1. Press NAV. A list of options appear. 2. Use the ARROW KEYPAD to highlight ‘Follow Route’ and press ENTER. 3. The Select Route page appears, with the ‘GPSMAP TOUR’ route highlighted. 4. Press ENTER, highlight ‘Activate’, and press ENTER again to activate the route. To zoom in to a closer map scale: 1. Repeatedly press the ZOOM IN key until you select the 3 nm scale.
You’ll now have a clearer picture of the route you are navigating. Keep in mind that when you exceed the usable range of the built-in database or the optional MapSource or BlueChart data in use, the range field displays ‘overzoom’ to indicate that you should exercise extreme caution using the map data. Press the ZOOM IN key to zoom into the 2 nm scale. Now that you’ve zoomed in a little closer to your route, you can pan ahead of your vessel with the cursor to review map items and create on-screen waypoints.
Getting Started Sonar Page Sonar Page Data Fields Adjustment Menu Simulated Fish Arch Depth Scale Bottom Whiteline Thermocline Sonar Page Outer edge beam returns Center beam return Frequency mode 14 Flasher The Sonar Page is where your GPSMAP 188/188C/238 Sounder becomes a powerful fishfinder/ flasher. The top left of the screen contains data fields, while the Adjustment Bar above the data fields allows direct access to the settings most commonly changed while using the Sonar Page.
Using the Adjustment Menu The Adjustment Menu allows direct access to the settings and features most commonly used on the Sonar Page. There are 10 main adjustment options available: Range, Zoom, View/Span, Gain, Target Level, Whiteline, Frequency, Depth Line, Noise Reject, and Scroll. The currently selected option appears in the upper left of the display with up and down arrows on either side of the option name. Getting Started Sonar Page To select an adjustment option from the Sonar Page: 1.
Getting Started Now that we’re navigating to an actual destination, let’s move on to the GPSMAP 188/188C/238 Sounder’s navigation pages by pressing the PAGE key. Compass Page/ Numbers Page Compass Page Current Destination Compass Ring Data Fields Pointer Arrow Compass Page The Compass Page provides graphic steering guidance to a destination waypoint, with an emphasis on the bearing to your destination and current direction of travel.
Getting Started To split the data fields: 1. Press MENU, then press ENTER. Highlight the ‘SPEED’ data field and press MENU. Numbers Page/ Highway Page 2. Highlight ‘Split Numbers’, then press ENTER. You will now see four new data fields. Press QUIT when done. 3. To return to the original configuration, repeat the above steps, but instead of ‘Split Number’, select either ‘Merge Numbers’ or ‘Defaults’. Press QUIT when done. Let’s move on to the Highway Page by pressing the PAGE key.
Getting Started Highway Page Whenever the GPSMAP 188/188C/238 Sounder is in simulator mode, you can also adjust your speed and course from the Highway Page using the ARROW KEYPAD. As you head toward each waypoint in the tour route, try adjusting your boat speed and course to get a feel for how the highway works. To adjust the simulated boat speed/heading from the Highway Page: 1. Press the UP arrow of the ARROW KEYPAD to increase the speed in 10 knot/kph/mph increments.
Changing Data Fields The data fields on the main pages may also be configured to display several different information categories (see pages 26-27 for the complete list). On the Highway Page, let’s change the ‘TIME TO NEXT’ field to ‘TIME OF DAY’. Getting Started Changing Data Fields/ Active Route Page To change a data field: 1. Press the MENU key to display the Highway Page options. 2. With ‘Change Numbers’ highlighted, press ENTER. 3. Use the ARROW KEYPAD to highlight ‘TIME TO NEXT’, then press ENTER.
Getting Started Main Menu Page As you’ve seen, the primary pages provide map and navigation information. The tour’s last page is the Main Menu page, which allows access to the GPSMAP 188/188C/238 Sounder’s waypoint, route, and planning functions, as well as various operational and navigation setup features, and celestial and tide data. Main Menu Page/ Deleting Waypoints The Main Menu is available from any page, and is accessed through the MENU key.
Congratulations! You’ve now gone through the basic operation of the Garmin GPSMAP 188/188C/ 238 Sounder. Your new digital chartplotter is a powerful tool with many advanced features not covered in the Getting Started tour. For detailed instructions on using these features or performing a specific task, please refer to the Quick Reference Guide or the appropriate reference section of this manual.
Map Page Reference The GPSMAP 188/188C/238 Sounder’s Map Page provides a comprehensive display of electronic cartography, plotting and navigational data. When using the unit with the optional BlueChart data or MapSource software, the map display shows your boat on a digital chart, complete with geographic names, map items, navaids, and a host of other chart features. It also plots your track and displays any routes and waypoints you create.
To activate and move the cursor: Reference 1. Press the ARROW KEYPAD in an UP, DOWN, LEFT or RIGHT direction. As you move the cursor, the distance and bearing from your present position to the cursor aredisplayed in the data window, along with the cursor’s position coordinates. When you zoom in cursor mode, the cursor is centered on the screen.
Reference The cursor may also be used to create new waypoints directly from the map. To create a waypoint with the cursor on an open map location: Map Page: Cursor and Zooming 1. Use the ARROW KEYPAD to move the cursor to the desired map position. 2. Press and quickly release the ENTER key to capture the cursor location (pressing and holding the ENTER key captures the current location, not the cursor location). 3. The ‘New Map Waypoint’ window appears.
The GPSMAP 188/188C/238 Sounder’s system has a built-in worldwide database to 20 mi, with more detailed coverage available through the use of the optional BlueChart or MapSource data. The GPSMAP 188/188C/238 Sounder displays cartography as long as there is chart information available for the range you’ve selected.
Reference • Full Screen Map/Show Data — toggles between a full screen map or a map with sonar information and/or data fields on the top half of the display. This allows for quick viewing of a full screen map. Map Page Options • Change Numbers — allows you to specify the type of data displayed in each data field used on the map display. This option is available from any of the main pages. To change a data field: 1. From the menu, use the ARROW KEYPAD to highlight the ‘Change Numbers’ option and press ENTER.
• POINTER – Arrow points to your destination • POSITION – Current position coordinates • SONAR – Compressed view of sonar data • SPEED – Speed over ground • TIME OF DAY – Current time • TIME TO DESTINATION – Time to final waypoint • TIME TO NEXT – Time to next waypoint • TO COURSE – Bearing to desired track • TOTAL AVERAGE SPEED – Total average speed • TOTAL TRIP TIME – Total travel time of trip, stopped and moving • TRACK – Current compass direction of travel • TRIP ODOMETER – Trip Odometer • TURN – Directi
Reference Map Page Options You may also choose to ‘merge’ the four medium, default data fields to a single, large field for better readability, or ‘split’ any or all of the default data fields to show 4 small data fields. This option is available from any of the main pages with the exception of the Numbers Page. One the Numbers Page, you may split each of the 3 large data fields into 4 medium fields, for a total of 12 data fields. To split or merge the Numbers fields: Single, large data field 1.
• Size Split — enables height adjustment of the Map Page sonar split screen. You may adjust the size of the map/sonar split window anywhere from 1/3 to 2/3 height from the top of the screen. You must be showing sonar information to use this option. Reference Map Page Options To resize the Map Page sonar split screen: 1. From the Map Page split screen, press MENU. 2. Highlight ‘Size Split’ and press ENTER. 3.
Reference Map Page Options General Tab General Tab Detail— Most, More, Normal, Less, Least: controls how much map detail you will see. This setting only applies to any map feature set to “Auto”. Those features which have a specified scale or turned “Off” are unaffected by this setting.
Waypoints Tab— Waypoints/Active Route Text— None, Small, Medium, and Large: controls the screen size of the name. Zoom— Auto, Off, 20 ft.–800 ft., 0.2 nm–800 nm: sets the maximum scale at which the feature appears on the screen. Some types of data will only show up to certain zoom scales. Points Tab— Spot Soundings/Tide Stations/Services/Navaids Text— None (except Spot Sound), Small, Medium, and Large: controls the screen size of the name. Zoom— Auto, On (Spot Soundings only), Off, 20 ft.–800 ft., 0.
Reference Map Page Options Track Tab— Saved Tracks/Track Log Zoom— Auto, Off, 20 ft.–800 ft, 0.2 nm–800 nm.: sets the maximum scale at which the feature appears on the screen. Some types of data will only show up to certain zoom scales. Other Tab Accuracy Circle— On/Off: toggles the circle “On” and “Off”. The circle represents the approximate accuracy of the unit based on EPE, DOP, and basemap quality. You position will be within the circle.
Sonar Page The Sonar Page is where your GPSMAP 188/188C/238 Sounder becomes a powerful fishfinder/ flasher. Fish are displayed as colored arches or as fish icons in three different sizes. Thermoclines are shown as shades of blue. The area of strongest sonar return (or whiteline) is displayed as solid white. Typically, the bottom will be the primary whiteline. A thin whiteline indicates a soft bottom while a thick whiteline will follow the contour of the bottom and show any objects of reasonable size.
Reference To change a setting back to ‘Normal’ or ‘Auto’: 1. On the adjustment window for the desired option, press MENU. Sonar Page: Adjustment Menu Zoom Adjustment Range Adjustment 4X Split Zoom Display (Dual Frequency Mode) 2. Select the desired setting and press ENTER. Adjustment Menu Options Range— sets the display depth range used for viewing. The unit can be set to automatically track the bottom or set to a user-specified depth range.
Once activated, the zoomed picture becomes the Sonar Page display. You may also cycle through the sonar zoom display levels by pressing the IN or OUT keys. The Zoom function can be deactivated by pressing the OUT key until the ‘No Zoom’ setting appears. View/Span— available when a Zoom scale other than ‘No Zoom’ is selected. The ‘View’ or ‘Span’ setting is used to change the viewing range of a zoomed display.
Depth Line— adds a horizontal depth line across the display which is used to measure the depth of underwater objects. The depth of the line appears in a box on the right side of the line. Press UP or DOWN on the ARROW KEYPAD to control the position of the line on the graph. The depth is displayed in a window on the right side of the line. To turn the Depth Line Off, press the ARROW KEYPAD UP until the setting bar is all the way at the top of the range and reads “Off”.
• Show/Hide Pointer — allows you to reference sonar items and mark underwater waypoints. This makes it easier to find and use an object such as a stump for a future fishing location. When using this feature, the Sonar Page pauses. The pointer does not move off the paused display and cannot show an area that has scrolled off the screen. The depth is updated while the display is paused, but the unit will not show any new sonar data until the standard Sonar Page is resumed.
Reference Sonar Page Options • Size Split — enables width adjustment of the Sonar Page split screen. This option is only available when a split screen zoom scale is selected. You may adjust the size of the split window anywhere from 1/4 to 3/4 width of the right half of the Sonar Page. To resize the Sonar Page split screen: Double-Arrow ‘Size Split’ Menu Options Resizing the Split Sonar Display Fish Symbols Off— All available information will be displayed. Suspended targets displays as fish symbols.
Water Type — since sound waves travel through ‘Fresh’ and ‘Salt’ water at different rates it is necessary to select the ‘Water Type’ to ensure accurate readings on the unit. Depth Number — controls the efficiency of the digital depth update rate.’Fast Update’ will update more quickly and is recommended for low-noise, deeper water (>50 ft.). ‘Auto’ is best for shallow water or high noise areas, will have a slower screen update and is best used if you travel a wide variety of depths.
Reference Sonar Page Options Keel Offset: Transducer at Surface Enter (+) positive number to show depth from bottom of keel Keel Offset: Transducer at Bottom of Keel Enter (-) negative number to show depth from surface Calibrate Water Speed — this is only available if you are using a speed-capable transducer/sensor. Calibration is required to ensure that the Water Speed displayed on your unit will be accurate.
Compass Page The GPSMAP 188/188C/238 Sounder features two different navigation pages: Compass and Highway. Whenever a NAV, Follow Track (TracBack), or Follow Route have been activated, the GPSMAP 188/188C/238 Sounder’s Compass Page will guide you to your destination with digital readouts and a graphic compass display, which includes a bearing pointer.
Reference Numbers Page/ Highway Page Numbers Page The Numbers Page provides a quick reference for the important data you want to display. The default page displays three large, user-selectable data fields showing a compass ribbon, speed and current position coordinates. You may also choose to show the three data fields in large lettering for better readability or you may ‘split’ any or all of the data fields to show 4 smaller data fields.
The Highway Page options menu provides access to functions and features relating to the Highway Page and the layout options. The data window, located at the top of the page, provides a user-selectable layout of various types of useful data. Each data field may be configured to display several data options. The data window layout may also be changed to display additional data fields and change the actual size of the data displayed. To display the Highway Page options: 1. Press MENU.
Reference Creating Waypoints Highlight ‘OK’ and press ENTER to use the default name and symbol. Creating and Using Waypoints The Garmin GPSMAP 188/188C/238 Sounder stores up to 3000 alphanumeric waypoints with a user-defined icon, comments and depth available for each waypoint.
6. To manually enter a set of coordinates, highlight the coordinates and press ENTER, then use the ARROW KEYPAD to enter the new coordinates and press ENTER when done. 7. When done, use the ARROW KEYPAD to highlight the ‘OK’ prompt and press ENTER to save the waypoint into memory. Creating Waypoints Graphically Waypoints may also be quickly created with the Map Page cursor, which allows you to ‘point and shoot’ at any map position or map feature to create a new waypoint.
Reference Creating Waypoints Additional Options For Creating Waypoints Waypoints may also be created by manually entering position coordinates through the Points tab of the Main Menu. This method can be useful for creating a waypoint at a specific latitude/longitude position from a chart. To create a new waypoint by entering location coordinates: Highlight the position field and use the ARROW KEYPAD to enter the desired position coordinates. 1. Press MENU twice to display the Main Menu.
3. To select another location from which to project a waypoint, highlight the field next to ‘From’ and press ENTER. The ‘Find’ screen appears. Highlight the desired type of location (waypoints, cities, etc.) and press ENTER. Use the submenus to narrow down your search (for more information see ‘Find’ on pages 38-39). Highlight the desired location and press ENTER. With ‘OK’ highlighted, press ENTER again. Reference Creating Waypoints 4.
Reference Reviewing/Editing Waypoints Reviewing and Editing Waypoints Once you have created and stored a waypoint, it may be modified, reviewed, renamed, moved, or deleted at any time through the Waypoint Review and Waypoint Edit pages. To access the Waypoint Review page: 1. Use the ARROW KEYPAD to highlight the desired waypoint on the Map Page. Waypoint Review Page— Highlight ‘OK’ and press ENTER to exit/save changes and return to the Map Page. 2. Press ENTER to display the Waypoint Review page.
Reference To change the comment/position coordinates/depth: 1. Highlight the desired field and press ENTER. Editing Waypoints 2. Use the ARROW KEYPAD to edit/enter the data. To drop to the next line, press to the right on the ARROW KEYPAD. Press ENTER when done. On the Waypoint Review and Waypoint Edit pages, you may also delete the selected waypoint, view the waypoint on the map, and move the waypoint on the map. To delete a waypoint: 1.
Waypoint Lists Reference Waypoint Lists The GPSMAP 188/188C/238 Sounder’s Main Menu Page features two waypoint submenu tabs, ‘User’ and ‘Proximity’, that let you manage a large number of waypoints quickly and efficiently. The submenu tabs also provide a continuously updated proximity waypoint alarm function that can be used to define an alarm circle around submerged hazards, shallow waters, etc. To access the waypoint submenus of the Main Menu: Submenu Tabs 1.
) Once a waypoint is deleted from the list, it cannot be recovered from the unit. It is advisable to backup important waypoints to a computer using an optional PC cable and interface software, save them to a data card, or write them down by hand. Reference Waypoint Lists To delete an individual waypoint from the ‘User’ list: 1. Use the ARROW KEYPAD to highlight the waypoint to be deleted. 2. Press MENU, highlight ‘Delete Waypoint’ and press ENTER. OR, press ENTER, highlight ‘Delete’ and press ENTER. 3.
Reference Waypoint Lists To add a proximity waypoint: 1. Use the ARROW KEYPAD to highlight an empty space on the Proximity list and press ENTER. The ‘Find’ screen appears. Highlight ‘Waypoints’ and press ENTER. 2. Use the ARROW KEYPAD to highlight the desired waypoint from the ‘By Name’ or ‘Nearest’ tab lists. The Waypoint Review page appears for the selected waypoint. 3. With ‘OK’ highlighted, press ENTER to confirm. The distance field is now highlighted. 4.
Going to a Destination Using the NAV key, the GPSMAP 188/188C/238 Sounder provides three ways to navigate to a destination: Go To Point, Follow Route, and Follow Track (TracBack). Once you are actively navigating, you will see a straight line that always runs from your current location to the destination on the Map Page. The easiest method for selecting a destination is the ‘Go To’ function, which lets you select a destination point, then quickly sets a direct course from your present position.
Reference To activate an existing waypoint or map item as a ‘Go To’ from the map display: 1. Use the ARROW KEYPAD to highlight the waypoint or map item on the screen and press NAV. Going to a Destination/ TracBack Navigation 2. With ‘Go To ’, press ENTER. To activate a new map point (non-map item) as a ‘Go To’ from the map display: 1. Use the ARROW KEYPAD to move the arrow cursor to the desired position and press NAV. 2. With ‘Go To MAP Point’ highlighted, press ENTER.
2. Use the ARROW KEYPAD to select ‘Save’ and press ENTER. 3. On the ‘Save Back Through’ window, highlight the desired time, date, or ‘Entire Log’ and press ENTER. 4. 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. Reference TracBack Navigation To change the name of the saved track, highlight the name field and press ENTER, make your changes and press ENTER again.
Reference • 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). TracBack Navigation/ MOB: Man OverBoard • 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.
Creating a Route The last way to navigate to a destination is to create a user-defined route. The Garmin GPSMAP 188/188C/238 Sounder lets you create and store up to 50 reversible routes (numbered 1-50), with up to 254 waypoints each. Routes can be created in two ways. The first way is by selecting points from the Map Page, allowing you to see each route graphically on-screen as you create the route.
Reference Creating a Route/ Following a Route To create a route using text: 1. Press the MENU key twice to display the Main Menu page. Use the ARROW KEYPAD to highlight the ‘Route’ tab. 2. Press the MENU key to display the route options page. Select the ‘New Route’ option and press ENTER. Or, highlight the first available blank route slot and press ENTER. 3. Press MENU, select ‘Edit as text’ and press ENTER. Choose the type of point you want to add to the route. 4.
2. Highlight the route you wish to navigate and press ENTER. 3. Choose ‘Activate’ or ‘Invert and Activate’ and press ENTER. (‘Activate’ will use the route as is, ‘Invert and Activate’ will reverse the route then activate it.) To deactivate (stop navigation) of a route: Reference Route List Page 1. Press the NAV key, highlight ‘Stop Navigation’ and press ENTER.
Reference Route Review Page Once you have created a route, the Route Review page allows you to edit a selected route. Route Review Page To access the Route Review page: 1. Press MENU twice and highlight the ‘Route’ tab. Route Name Data Fields 2. Highlight the name of the route you wish to review and press ENTER. The Route Review page also allows you to enter a 15-character name for any listed route. By default the name includes the first and last waypoints in the route.
• Edit on Map — review and modify the route displayed for each point (waypoint or map item) on a map page. You may also use the cursor to insert a new route point on a route leg, review the waypoint or map item. To edit a route on the map: Reference Editing Routes 1. From the Route Review page, press MENU, highlight ‘Edit on Map’ and press ENTER. To review a route point: 1. Highlight the point and press ENTER. The Review page appears.
Reference Editing Routes The GPSMAP 188/188C/238 Sounder’s route edit mode also allows you to insert a new route point in any route leg using the map cursor. To insert a new point between two existing route waypoints: 1. Use the ARROW KEYPAD to select the leg in which you want to insert the new waypoint (the route line will highlight and change to a dotted line when the leg is selected) and press ENTER. Highlight the route leg on which you wish to insert a waypoint and press ENTER. 2.
• Trip Planning — The Route Review and Active Route pages also display trip-planning information for each leg or the entire route. Available information includes Course, ETA, Fuel (to point), Leg Distance, Leg Fuel, Leg Time, Sunrise and Sunset (at point location) and Time To (point). Reference Editing Routes To use the trip planning feature: 1. Highlight the desired route from the Route List and press ENTER to display the Route Review page. 2.
Reference Active Route Page Active Route Page Whenever you have activated a route in the GPSMAP 188/188C/238 Sounder, the Active Route page shows each point (waypoint or map item) of the active route, with the point name, distance and choice of Course, ETA, Fuel to point, Leg Distance, Leg Fuel, Leg Time, Sunrise and Sunset at point location, or Time To point for each point from your present position. The current destination point, the ‘active’ point, is marked with an arrow icon.
Find Key The FIND key allows you to search the units for user waypoints, map items, and any optional BlueChart or MapSource information loaded on a data card. Press the FIND key to search for items from your current location by default. You may also search from other locations. When you press FIND, a list of available items to search from appears. The default items are Waypoints, Cities, Tide Stations, and Transportation.
To view details about an item: Reference 1. With the desired item highlighted in the search results list, press ENTER. Find Options Additional Information Tabs Distance, Bearing, Coordinates of item Additional Option Buttons 2. An Information page appears with details about the item organized in a tabbed format.
Main Menu Page Reference The GPSMAP 188/188C/238 Sounder’s Main Menu Page provides access to various waypoint, system, navigation and interface management, and setup menus in an easy to use “tab” format. The Main Menu page is available from any page in the GPSMAP 188/188C/238 Sounder’s system, and is accessed through the MENU key. See pages 2-3 for additional instructions changing settings and entering data. Main Menu Page To access the Main Menu Page: Submenu Tabs 1. Press MENU twice.
Reference Main Menu: GPS Tab Receiver Status Accuracy DOP Sky View Differential Status Signal Strength Bars Main Menu— GPS Tab 90° Center dot - 90° above the horizon Inner ring- 45° above the horizon Outer ring the horizon 45° 68 188188C238 Manual Part 2.indd 68 • • • • • • • • • Pages – enables main pages to be shut off, turned on, or ‘jumped to’. Map – sets up Map Page features, zooms, and text size. See pages 29-32. Temp – sets up and shows the water temperature log.
WAAS Capability The GPSMAP 188/188C/238 Sounder is capable of receiving WAAS (Wide Area Augmentation System) satellite signals. WAAS is an FAA (Federal Aviation Administration) funded project to improve the overall accuracy and integrity of the GPS signal for aviation use, but land/sea based users may also benefit from this system. At this time, the system is still in the development stage and is not fully operational. There are currently two WAAS satellites that can be received in the U.S.A.
Reference Main Menu: GPS Tab When the GPSMAP 188/188C/238 Sounder is using a differential correction signal (either WAAS or DGPS), a “D” is displayed at the bottom of the signal strength indicator bars for the satellites that are corrected. 70 188188C238 Manual Part 2.indd 70 The status field will show one of the following conditions: • Looking For Satellites – the receiver is looking for any satellites. • AutoLocate – the receiver is looking for any satellite whose almanac has been collected.
The Differential SNR (Signal to Noise Ratio) indicates, on a scale to 0-30db with 30db being the best, the strength of the DGPS signal being received. If no optional DGPS receiver is used with the GPSMAP 188/188C/238 Sounder, the ‘DGPS Rcvr’ field displays ‘Off. The SNR will depend upon the mounting of your DGPS receiver and the distance from the DGPS transmitting station. The GPS Info tab features an options menu that provides access to functions and features relating to the GPS Info display.
Reference Main Menu: Tide Tab Station Name Date Tide Chart Tide Tab— shows a graphical chart that displays tide station information in a 24-hour span starting at midnight station time. You can choose from different dates and over 3000 tide stations around the USA coastline, Alaska, Hawaii, western Canada and several of the Caribbean islands. The top of the page displays the tide station being referenced, below that the date.
To view the chart for a tide station nearest to your current location: Reference 1. From the Tide tab, highlight the ‘At’ field and press ENTER. 2. Press MENU, select ‘Nearest to Boat’ and press ENTER. Main Menu: Tide Tab 3. Select the desired station from the list and press ENTER. 4. Highlight ‘Show Chart’ or ‘OK’ and press ENTER. If you are not within this range, you will see a message “None Found”. Use the ‘Nearest To Other’ Find option and select a location closer to a tide station.
Trip Tab— displays Trip Odometer, Moving Average Speed, Total Average Speed, Maximum Speed, Stopped Time, Moving Time, Total Time, and Odometer. Reference To reset the trip data: Main Menu: Trip Tab/ Celestial Tab 1. Highlight ‘Reset Trip’, ‘Reset Max Speed’, ‘Reset Odometer’ or ‘Reset All’ and press ENTER. Main Menu— Trip Tab Celes (Celestial) Tab— displays celestial data for sun and moon rise/set, moon phase, and approximate skyview location of the sun and moon.
Points Tab— contains the ‘User’ and ‘Proximity’ waypoint lists. See pages 50-52. Reference Route Tab— contains a list of available routes. See pages 57-63. Track Tab— lets you specify whether or not to record a track log (an electronic ‘breadcrumb trail’ recording of your path), define how it is recorded, or save track log data for future use. The Track Tab also provides an indicator of the memory used for the active track log and options to clear the track memory or start a TracBack route.
Reference • Value— defines the distance or time used to record the track log. • Save— allows you to save the current active track log. Main Menu: Track Tab • Erase— allows you to clear the active track log currently stored in memory. Saved Tab The ‘Saved’ tab displays and manages a list of any saved track logs, allows TracBack activation, map display of saved logs. The active log stores up to approximately 2500 track log points, based upon the criteria specified in the Track settings.
DSC Tab— allows to control and set up DSC (Digital Selective Calling) features on the unit. What is Digital selective calling (DSC)? Digital Selective Calling (DSC) uses marine VHF radio and Global Positioning System (GPS) technologies to transmit and receive location information. DSC is used by mariners to assist them in two major areas: Distress Calls and Position Reporting.
Reference Main Menu: DSC Tab 78 188188C238 Manual Part 2.indd 78 HOW ARE MMSI ASSIGNMENTS OBTAINED? Non-commercial users (e.g. recreational users who remain in domestic waters and only carry VHF, EPIRB (Emergency Position Indicating Radio Beacons), and Radar) are not required to have a FCC ship station license. The FCC and Coast Guard have authorized some second and third party vendors to assign MMSI numbers. This service is limited to registering recreational vessels only.
MMSI number attached to the call (if you have DSC support). Any DSC-equipped mariner (on sea or land) within range can receive the call. When the Garmin GPSMAP 188/188C/238 is connected to a VHF with DSC support, the GPS unit displays a Call List, Log, and a Directory available to store incoming information received from another user’s DSC capable VHF/GPS combination. Basic wiring is required for the Garmin unit and VHF radio to send and receive NMEA data from each other (pg.87).
Reference Main Menu: DSC Tab DSC Entry Review DSC Call List The DSC Call List displays the current calls received. The GPS can manage up to 50 calls. When ‘calls’ are received, they are updated constantly to give the most current information, even if the unit is left unattended. Any entry from the Call List can be selected to show an Entry Review. DSC Log When DSC calls are received, they are automatically stored in the Log, with the latest call at the top. The unit may store up to 100 logs.
There are two ways to add a new entry into the directory. Reference To add a new Directory entry: 1. Press Menu, then highlight ‘New Item’ and press ENTER/MARK. Main Menu: DSC Tab 2. Or, with the Directory Tab highlighted press the Arrow Keypad DOWN, highlight an empty field and press ENTER/MARK to access the New Directory Item window. The New Directory Item window allows you to input information of a known contact. To add the MMSI number, Name, or Comment: 1.
Reference Main Menu: DSC/Card Tabs A user also has the ability to simulate a Distress Call or a Position Report on this page. This is helpful for practice before connecting to the real system. The Distress Call simulator also helps to check if alarms are working properly. To run a simulation: 1. Place the chartplotter into simulation (see pg. 7). 2. From the Main Menu, select the DSC tab, then highlight the Setup tab. 3. Highlight which simulation you wish to run and press ENTER/MARK.
Time Tab— displays the current time and date, allows you to adjust the 12 or 24-hour time format, enter a time zone, and adjust for daylight savings to show correct local time. The following options are available: • Time Format – choose from 12 or 24-hour (military) time format. • Time Zone – choose your correct time zone to show correct local time or enter a UTC Offset. The UTC (also called Greenwich Time) offset is how many hours you are ahead or behind the time line.
Reference Map Tab— contains setup options for the Map Page. See pages 29-32. Hiway Tab— contains setup options for the Highway Page. See pages 42-43. Main Menu: Temp Tab/ System Tab Temp (Temperature) Tab— displays the water temperature log (if equipped with a temperature transducer/sensor). The chart reads from right to left, so that the most recent temperature measured is displayed on the far right side of the chart.
Track* – lets you enter a heading. Speed* – lets you enter a speed. Transducer* – lets you simulate using a Depth Only, Temp Only, or Temp/Speed transducer. * These fields will only appear when the unit is in Simulator Mode. • System Information – displays the unit’s software, basemap version, and electronic serial number. Reference Main Menu: System Tab/ Units Tab Press MENU for the following options: • Defaults – restores settings on Systm page to default values.
Reference Main Menu: Units Tab , The Units tab settings will affect how navigation information is displayed on the GPSMAP 188/188C/238 Sounder. When in doubt, seek assistance. If you are using a map or chart in conjunction with your GPS, make sure the settings under the ‘Units’ tab of the GPSMAP 188/188C/238 Sounder match that of the map or chart. This information should be displayed somewhere on the map or chart.
Comm (Communications) Tab— lets you control the input/output format used when connecting your GPSMAP 188/188C/238 Sounder to external NMEA devices, a DGPS beacon receiver, a personal computer, another Garmin GPSMAP 188/188C/238 Sounder, etc. If a DGPS receiver is used, WAAS capability will automatically be turned to ‘Off’. The unit supports two input/output ports. See page 95 for more information on wiring and NMEA information.
Reference To select a transfer mode: 1. Use the ARROW KEYPAD to select ‘Garmin Data Transfer’ in the ‘Serial Data Format’ field. Main Menu: Comm tab 2. Highlight the ‘Transfer Mode’ field and press ENTER. 3. Use the ARROW KEYPAD to select the desired setting and press ENTER. You may also adjust the NMEA output to enable/disable certain sentences and adjust the number of Lat/Lon output precision digits. You must have one of the ports set to NMEA In/NMEA Out to use this option.
The “Status” field will show one of the following: • • • • Tuning – unit is attempting to tune to the specified frequency and bit rate. Scanning – unit is automatically scanning through the frequencies and bit rates. Receiving – unit is receiving DGPS signal and ready for operation. Check Wiring – unit is not making connection with DGPS receiver. Reference Main Menu: Comm Tab When the unit is receiving a DGPS signal, the “SNR” (Signal to Noise Ratio) and “Distance” fields will show data.
Reference Main Menu: Comm Tab/ Alarm Tab Advanced NMEA Setup Page Advanced NMEA Output Setup The GPSMAP 188/188C/238 Sounder NMEA data transmission can be customized to change the precision of the Lat/Lon minutes, set up the waypoint IDs, and keep the output rate at two seconds. If the unit is set up to output all of the available NMEA sentences, the output rate may exceed two seconds. The ‘Advanced NMEA Output Setup’ page allows you to turn on/off the GPS status (GSA.
Battery – sets an alarm to sound when the battery is reaching a critical state of discharge. DGPS – sets an alarm to sound when the unit loses a differential fix. Accuracy – sets an alarm to sound when the GPS position accuracy falls outside the user-set value. Nav Tab Anchor Drag – sets an alarm to sound when you’ve exceeded a specified drift distance. Enter a value in the distance field and use the control field to turn the alarm on and off.
Appendix A Antenna Installation Installing the GPSMAP 188/188C/238 Sounder The GPSMAP 188/188C/238 Sounder must be properly installed according to the following instructions to get the best possible performance. To complete the installation, you’ll need the appropriate fasteners and a 1” x 14-thread marine antenna mount available at most marine dealers. (If you have a GPSMAP 188 with an internal antenna, skip to the next page.) When in doubt, seek professional assistance.
Mounting the GPSMAP 188/188C/238 Sounder Unit The GPSMAP 188/188C/238 Sounder’s compact, waterproof case is suitable for mounting in exposed locations or at the nav station. The unit comes with a gimbal bracket that can be used for surface or overhead mounting.
Appendix A Unit Installation The GPSMAP 188/188C/238 Sounder can be flush mounted on a flat panel. When flush mounting the GPSMAP 188/188C/238 Sounder, be sure to choose an appropriately sized location for the unit and leave 1.25” (32mm) clearance below the data card slot for inserting/removing data cards. For flush mounting the GPSMAP 188C unit, refer to the instructions on the Flush Mount Template (190-00264-00).
Connecting the Power/Data Cable The power/data cable connects the GPSMAP 188/238 Sounder to a 8-35 (GPSMAP 188C 10-35) volt DC system and provides interface capabilities for connecting external devices. The color code in the diagram below indicates the appropriate harness connections. Appendix A Wiring and Interfacing (TX COM 2) You can download a copy of Garmin's proprietary communication protocol from the Help and Support section of our web site at www.garmin.com.
Appendix A Selecting a Transducer Transducers The transducer acts as the eyes and ears of your new sonar. Proper transducer selection and installation are critical to the operation of your unit. The transducer transmits sound waves toward the bottom in a cone shape. The larger the cone angle, the larger the coverage area at a given depth. A wide cone angle transducer works best in shallow water. The wide cone angle provides a large coverage area, but at a decreased bottom resolution.
Proper transducer installation is key to getting the best performance from your new unit. If the transducer lead is too short, extension cables are available from your Garmin dealer. DO NOT cut the transducer lead or any part of the transducer cable, as this will void your warranty. The cable cannot be spliced and connected to any existing (Garmin or non-Garmin) transducer cables. Appendix A Mounting the Transducer Following are some tips and basic installation instructions for some popular transducers.
Appendix A Mounting the Transducer To avoid drilling a hole to mount a thru-hull transducer, a transom mount transducer may be used with epoxy inside a boat (“shoot-thru-hull” installation). For a transducer to be mounted inside the hull (shoot-thru, not thru-hull), the boat must be fiberglass, no core (contact your boat manufacturer if you are unsure).
Testing the Installation While it is possible to perform some checks with the boat trailered, the boat should be in the water to properly test the sonar portion of the installation. Appendix A Testing the Installation Press the POWER button and the GPSMAP 188/188C/238 Sounder should power on. If the unit fails to power on, verify that the wiring adapter is seated properly in the back of the unit, the Red and Black wires are connected to the correct polarity, and that the fuse is installed and not blown.
Appendix B Installing and Removing Data Cards Installing and Removing Data Cards The GPSMAP 188/188C/238 Sounder uses optional Garmin marine BlueChart and MapSource data cards to display digital charts and maps on-screen. You may also transfer user data to data cards (pg 82) Data cards are installed in the card slot located at the bottom right of the unit. Data cards may be installed or removed at any time, whether the unit is on or off. To install a data card: 1.
Cleaning Appendix C The GPSMAP 188/188C/238 Sounder is constructed of high quality materials and does not require user maintenance other than cleaning. Clean the unit using a cloth dampened with a mild detergent solution and then wipe dry. Avoid chemical cleaners and solvents that may damage plastic components. Maintenance , WARNING: The GPSMAP 188C Sounder lens is coated with a special anti-reflective coating which is very sensitive to skin oils, waxes, and abrasive cleaners.
Appendix D Loran TD Loran TD System LORAN C is a radio navigation aid operated and maintained in the United States by the United States Coast Guard. The name LORAN is an acronym for “LOng RAnge Navigation”. The LORAN system covers the entire United States and the U.S. Coastal Confluence Zone. From the perspective of a mariner, the system is used for ocean and coastal navigation.
To select the Loran TD position format: 1. On the Units tab of the Main Menu, press MENU, highlight ‘Loran TD On’ and press ENTER. OR: Appendix D Loran TD 1. On the Units tab of the Main Menu, highlight the Position Format field and press ENTER. 2. Highlight ‘Loran TD’ and press ENTER. The ‘LORAN TD Setup’ window contains the fields to select the Loran GRI-Chain Number, Primary and Secondary Stations, and TD Offsets. To setup Loran TD from the Main Menu: 1.
Appendix E Map Datum ) The GPSMAP’s built-in world-wide database includes coverage down to 20 n.m. (30 km). Note that the GPSMAP 188/188C/238 Sounder basemap is valid to 75º north and 60º south of latitude. ) The ‘User’ datum is based on a WGS-84 Local datum and is an advanced feature for unlisted or custom datums. To learn more, check your local library or on the world wide web for educational materials on datums and coordinate systems. 104 188188C238 Manual Part 2.
Kandawala Kandawala- Sri Lanka NAD27 Mexico N. American 1927- Mexico Kerguelen Islnd Kerguelen Island NAD27 San Sal Kertau 1948 West Malaysia, Singapore North American 1927- San Salvador Island L. C. 5 Astro Cayman Brac Island NAD83 Liberia 1964 Liberia 1964- Liberia North American 1983- Alaska, Canada, Central America, CONUS, Mexico Luzon Mindanao Luzon- Mindanao Island Nhrwn Masirah Nahrwn- Masirah Island (Oman) Luzon Philippine Luzon- Philippines (excluding Mindanao Isl.
Appendix F Messages The GPSMAP 188/188C/238 Sounder uses an on-screen pop-up message system to alert you to unit operating characteristics. Press the ENTER key to acknowledge and return to the page you were viewing. Alarm Clock— The alarm clock has sounded. Alarm Voltage Set Too High— Voltage range must be between 8.0 and 35.0 volts for the GPSMAP 188/238 (GPSMAP 188C 10.0 to 35.0 volts). Alarm Voltage Set Too Low — Voltage range must be between 8.0 and 35.0 volts for the GPSMAP 188/238 (GPSMAP 188C 10.
Proximity Alarm List is Full— You have used all ten proximity waypoints. Proximity Alarm Waypoint— You have entered the alarm radius for the proximity waypoint indicated. Proximity Overlaps Another Proximity Waypoint—The alarm radius specified overlaps the area specified for another proximity waypoint. Adjust the distance. Route Already Exists: — You have entered a route name that already exists in memory. Modify the route name or delete the previous route name.
Appendix G Navigation Terms 108 188188C238 Manual Part 2.indd 108 Avg Speed— The average of all second-by-second speed readings since last reset. Bearing (BRG)— The compass direction from your present position to a destination waypoint. Course— The desired course between the active ‘from’ and ‘to’ waypoints. Distance (Dist)— The ‘great circle’ distance from present position to a destination waypoint.
Appendix G Navigation Terms DIS NORTH NORTH TAN CE TO DES TINA TIO N DESTINATIO WAYPOINT BRG TRK F SP EE D SE UR CO DES IR TRA ED CK OF position readings. Off Course— The distance you are off a desired course in either direction, left or right. Also referred to as ‘cross-track error’ or ‘course error’. Speed— The current velocity at which you are travelling, relative to a ground position. Also referred to as ‘ground speed’.
Appendix H The chart below gives an approximate UTC (Universal Time Coordinate) time offset for the various longitudinal zones. Check with local charts for more detailed information. If you are in daylight savings time, add one hour to the offset. Longitudinal Zone Offset Longitudinal Zone Offset Time Offsets W180.0º to W172.5º -12 E007.5º to E022.5º +1 W172.5º to W157.5º -11 E022.5º to E037.5º +2 W157.5º to W142.5º -10 E037.5º to E052.5º +3 W142.5º to W127.5º -9 E052.5º to E067.
Understanding Sonar If you are unfamiliar with basic sonar, or need help determining what is displayed on the graph, this section may be for you. This section is intended to help the novice user gain some understanding of how the GPSMAP 188/188C/238 Sounder operates and how it can help improve their fishing productivity. To understand what the unit is displaying, it is important to have a general knowledge of how the unit works and how it determines what to display.
Appendix I Transducer Coverage Transducer Coverage The area covered by the transmitted sound waves is determined by the cone angle of the transducer and the water depth. Cone angles may vary between different types of transducers. For example, a 50kHz frequency may provide a “wide” 40° cone angle, with a coverage width that is approximately 2/3 of the water depth. As shown in the sidebar, the 40° cone angle (50kHz frequency) approximately covers the area of a 20 foot diameter circle at a 30 foot depth.
Understanding the Graph It is important to understand that the unit does not display a 3-D representation of the underwater environment. The unit can display multiple things at the same time, but cannot determine where the return originated – only when it was received. Examples 1 and 2 provide a look at the underwater world from a top view, and illustrate how these views would be displayed on the graph. On both graphs it appears the fish and tree are side by side as shown in Example 1.
Appendix I Understanding the Chart ) Whiteline can also help you to determine the type of bottom structure that is displayed on the chart. By determining the hardness of the structure, you can make a better informed decision on the type of structure. Structure is hard— probably a rock or stump 114 188188C238 Manual Part 2.indd 114 Structure is soft— probably a mud pile Whiteline The GPSMAP 188/188C/238 can help you to determine if the bottom is hard or soft.
Thermoclines One of the unique features offered by Garmin is See-Thru technology. See-Thru technology allows the GPSMAP 188/188C/238 to “see” through thermoclines and helps locate fish where they live; and fish love thermoclines! A rough definition of a thermocline is a break in water where the water temperature changes faster than the water above it. Thermoclines are shown as the weakest colors (see pg. 14) Appendix I Understanding the Chart Thermocline 115 188188C238 Manual Part 2.
Appendix J Physical Specifications Size: 188: 6.2" H x 6.3" W x 2.6" D (15.8cm x 16.0cm x 6.6cm) 188C: 6.2" H x 6.3" W x 3.7" D (15.8 cm x 16.0 cm x 9.4 cm) 238: 7.5" H x 7.7" W x 2.6" D (19.1 x 19.6 x 6.6 cm) Weight: 188: 1.7 lbs. (.77Kg); 188C: 2.6 lbs. (1.18 kg); 238: 2 lbs. (.91Kg) Display: 188: 5.5" diagonal (14.0cm) 238: 7.1" diagonal (18.00cm) high-contrast, 10-level grayscale FSTN LCD with adjustable backlighting (360 x 240 pixels 188C: 5.0" diagonal (12.
DGPS (WAAS) Accuracy Position: 3 meters (10 feet), 95% typical* Velocity: 0.05 meters/sec steady state Dynamics: 6g's Appendix J Specifications * Warm = all data known; Cold = position, time and almanac known; AutoLocate = almanac known, position and time unknown; Skysearch = no data known. ** Subject to accuracy degradation to 100m 2DRMS under the U.S. DOD-imposed Selective Availability Program. Power Source: GPSMAP 188/238: 8-35v DC GPSMAP 188C: 10-35v DC Usage: 188/238: 8 watts max. at 13.
Appendix K Index A Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . vi Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69 Accuracy Alarm . . . . . . . . . . . . . . . . . . . . . . . . . . . 91 Accuracy Circle . . . . . . . . . . . . . . . . . . . . . . . . . . . 32 Active Route Page. . . . . . . . . . . . . . . . . . . . 19, 43, 64 Adjustment Menu. . . . . . . . . . . . . . . . . . . . 15, 33-36 Alarms . . . . . . . . . . . . . . . . . . . . . . . . . . .
GPS Status . . . . . . . . . . . . . . . . . . . . . . . . . . 3, 68-70 ‘Go To’ a Point . . . . . . . . . . . . . . . . . . . . . . . . . 53-54 Going to a Destination . . . . . . . . . . . . . . 11-12, 53-54 H Heading . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 86 Heading Line . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31 Highway Page. . . . . . . . . . . . . . . . . . . . . 17-19, 42-43 I IN Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Registration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . i Restore Unit Defaults . . . . . . . . . . . . . . . . . . . . . . . 85 Reviewing Waypoints . . . . . . . . . . . . . . . . . . . . . . . 48 Route List Page. . . . . . . . . . . . . . . . . . . . . . . . . . . . 59 Route Review Page . . . . . . . . . . . . . . . . . . . . . . . . . 60 Routes Activating/Following . . . . . . . . . . . . 12, 58-59 Copying . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59 Creating . . . . .
Warnings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iii Warranty . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . iv Water Immersion . . . . . . . . . . . . . . . . . . . . . . . . . 101 Water Speed, Calibrating . . . . . . . . . . . . . . . . . . . . 40 Water Temp Alarm . . . . . . . . . . . . . . . . . . . . . . . . . 91 Water Type . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39 Waypoint Lists . . . . . . . . . . . . . . . . . . . . . . . . .
188Ccover.
For the latest free software updates (excluding map data) throughout the life of your Garmin products, visit the Garmin web site at www.garmin.com. © Copyright 2003 Garmin Ltd. or its subsidiaries Garmin International, Inc. 1200 East 151st Street, Olathe, Kansas 66062, U.S.A. Garmin (Europe) Ltd. Unit 5, The Quadrangle, Abbey Park Industrial Estate, Romsey, SO51 9DL, U.K. Garmin Corporation No. 68, Jangshu 2nd Road, Shijr, Taipei County, Taiwan www.garmin.com Part Number 190-00216-10 Rev. A 188Ccover.
