Garmin 128 Owner's Manual

Also see for GPS 126: Specifications

Garmin 128 Owner's Manual Manual pdf 52 page image

User Grid OptionThe user grid option lets you create a user-definedposition format by establishing factors such as longitudeof origin, scale, and false Easting or Northing.To define a user grid:1. Select ‘User Grid’, and press F. Enter values forlongitude origin, scale, false Easting and Northing,then press F. Highlight ‘SAVE?’, and press F.Map DatumsThe ‘datum’ field is located just below the ‘position’field and comes with a WGS 84 default setting.Although 106 total map datums are available for use(see Appendix D for map datums), you should onlychange the datum if you are using maps or charts thatspecify a different datum than WGS 84.To select a map datum:1. Highlight the ‘datum’ field, and press F.2. Select the desired setting, and press F.To define a user datum:1. Highlight the ‘datum’ field, and press F.2. Scroll through the map datum options until ‘User’appears, and press F.3. Enter values for ‘DX’, ‘DY’, ‘DZ’, ‘DA’, and ‘DF’ using therocker keypad, and press F.4. Highlight ‘SAVE?’, and press F. The setup menuwill reappear.CDI Scale SettingsThe course deviation indicator (CDI) field lets youselect the +/- range of the CDI bar scale on the HighwayPage. Three scales are available: +/- 0.25 (default), 1.25,and 5.0 miles or kilometers. Note: This CDI value rep-resents the full deflection of scale to either side.To enter a CDI scale setting:1. Highlight the ‘cdi scale’ field, and press F.2. Select the desired setting, and press F.Units of MeasureThe GPS 126/128 lets you select statute (default),nautical, or metric units of measure for all ‘speed’ and‘distance’ fields.Datums, CDISettings, &MeasurementREFERENCE48The default map datumwill cover worldwide nav-igation. However, if youare using a paper map orchart which uses a differ-ent map datum than WGS84, then you may wish toswitch to that datum.The user datum featureallows you to define theearth model used to calcu-late position coordinates.WARNING: Incorrectentries may result in sub-stantial position errors.