TM 1-1510-218-10 3-12 90B  hasn't  been  used  for  the  previous  6  months  or longer.      Collecting   new   almanac   data   takes   place automatically  if  the  data  is  more  than  6   months old.   This  will  usually  take  about  6  minutes  but  no  more than 12 minutes. (2)   The  aircraft  must  be  located  so  the  GPS antenna has an unobstructed view of the sky. (3)   It is very helpful for the KLN 90B to have the correct date, time, and position.  This information is stored in the battery-backed  memory  of  the  KLN  90B so it is not normally required to update it.  If acquisition time is not important, then it is not necessary to update the   date,   time,   and   position.      Refer   to   Paragraph 3-7e(6) for setting the  date and time, if necessary.  To update the position: 1.   Select    the    Setup    1    page    by    first turning  the  left  outer  knob  to   SETUP displaying a SET page annunciated in the  lower  left  segment  of  the  display.   Turn the left inner knob until the SET 1 page is selected. 2.   Press  the  left   CRSR  button  to  bring the cursor on the page over the  WPT  field. 3.   Use    the    left    inner    knob    to    enter characters  and  the  left  outer  knob  to move the cursor until the identifier for the location is entered. 4.   Press   the    ENT   button   to   view   the waypoint page on the right side. 5.   Press     the     ENT button again to approve the entry. NOTE As an alternative, the latitude and longitude  of  the  present  position  can  be entered    directly    instead    of    entering    a waypoint identifier. 6.   Use the left outer knob to position the cursor over CONFIRM? 7.   Press the ENT button. NOTE The   groundspeed   and   heading   fields   are not used for initialization in the aircraft.  If the   KLN   90B   is   in   the   take-home   mode, entering a groundspeed will allow the KLN 90B  to  fly  along  the  active  flight   plan  (or direct   to   a   waypoint)   starting   from   the initialization  waypoint.    A  heading  may  be entered in the initial heading field while in the  take-home  mode  if  the  one  offered  is not   desired.      If   the   take-home   mode   is used,  the  KLN  90B  must  be  initialized   to the    aircraft's    location    when    it    is    re- installed. 8.   Use the left knobs to select the NAV 2 page.    When  the  KLN  90B  reaches the  NAV  ready  status  and  is  able  to navigate,  the  NAV  2  page  will  display the     present     position.          Verify     the latitude   and   longitude   or   the   VOR radial     and     distance     displays     are correct. j. Selecting Waypoints.   There are five types of   waypoints:   airports,   VOR's,   NDB's,   intersections, and    supplemental.        Waypoints    in    the    published database fall into one of the first four types.  Up to 250 user defined waypoints may be created and defined as any  of  the  five  types.    There  are  three  methods  to select   a   specific   waypoint   for   viewing:   enter   the waypoint's identifier directly, scan through the waypoint identifiers in alphabetical order, or enter the waypoint's name.  If the waypoint is an airport, it may also be selected by entering the city where the airport is located. (1)   Selecting  Waypoints  By  Identifier.    The most  direct  way  of  selecting  a  specific  waypoint  is  to simply  enter  the  identifier  directly   on  the  appropriate waypoint page. 1.   Rotate  the  right  outer  knob  to  select the  appropriate  waypoint  type  page.   For  the  airport  type  waypoints,  rotate the right inner knob to select the APT 1 page if it is not already in view.  The airport   identifier   can   be   entered   on any  of  the  eight  airport  pages  but  the APT 1 page displays the airport name. 2.   Press  the  right  CRSR  button  to  bring the cursor on the screen over the first character of the identifier.  Check the right inner knob in the in position. 3.   Turn the right  inner knob to select the first character of the identifier.