TM  1-1520-240-10            3-3-17 CONTROLS/ INDICATOR FUNCTION MGRS Selects Military Grid-Ref- ence System (MGRS) navi- gational mode of operation. LAT/LONG Selects latitude/longitude navigational mode of opera- tion. GPS LDG Places navigation set in GPS landing mode of opera- tion. This mode provides real-time, tactical precision landing guidance informa- tion to the HSI indicator. DISPLAY switch Selects navigation data for display. WIND-UTC DATA Used for wind speed and di- rection, UTC time, sea cur- rent, surface wind, GPS sta- tus and data load functions. XTK/TKE KEY Displays steering (cross track distance and track angle error) information and GPS variable key status. Selection of fly to destination by direct entry of two digit destination number. GS/TK NAV M Displays ground speed, track angle and selection of GPS and navigation mode. PP Displays present position, al- titude and magnetic varia- tion. DIST BRG TIME Displays distance, bearing and time information to the destination or course selec- ted. Selection of fly to des- tination can be accom- plished by direct entry of two digit destination number. WP TGT Accesses waypoint or target data (landing data, variation, motion). Selection of des- tination for display/entry by direct entry of two digit des- tination number. DATUM ROUTE Accesses datum and steer- ing/route functions. MAL Indicator Lamp Lights when navigation set malfunction is detected by the built-in test circuitry. In the event of an intermittent malfunction, the system may operate correctly but must be cycled to OFF position then to on, to extinguish the MAL light. CONTROLS/ INDICATOR FUNCTION BRT and DIM Keys Used to brighten or dim the light intensity of the LCD dis- play. Four Line Alpha- Numeric Display Displays alphanumeric char- acters, as determined by the setting of the DISPLAY switch, the MODE switch and operation keyboard. The keys activate function upon release and are to be released immediately after being depressed. TGT STR Key Stores present position data in the indicated target store/ memory location (90-99) when depressed and re- leased. KYBD Key Used in conjunction with the keyboard to allow data dis- play and entry into comput- er. Keyboard and LTR Keys Used to set up data for entry into memory. When DIS- PLAY switch is set to a posi- tion in which new data is re- quired and KYBD key is pressed, data may be dis- played on the appropriate in- put field of display. To dis- play a number, press the corresponding key or keys (6 through 9). To display a letter, first depress the LTR key corresponding to the position of the desired letter on a key. Then depress the key which contains the de- sired letter. Example: To en- ter an L, first depress the LTR RIGHT key then de- press the 4 key. INC and DEC Keys Used to increment or decre- ment the displaced WAY- point/Target number when the DIPLAY switch is set to WP/TGT. To access P, de- press the LTR LEFT key fol- lowed by the 6 key, display waypoint 99 then depress the inc key, or display way- point 99 then depress the INC key, or display waypoint 00 key then depress the DEC key. Also used to incre- ment or decrement the Fly- To-Destination number when the DISPLAY switch is