TM 55-1510-222-10 any   display   of   59.      9   arc-seconds.      The   value   in computer is as loaded by operator. (6) To insert TACAN coordinates: (a) Insertion of UTM TACAN station data: NOTE Prior to pressing the INSERT/ADVANCE    pushbutton,    any incorrectly loaded data can be corrected by pressing CLEAR pushbutton and loading correct data. 1.  Data selector - UTM WY PT. 2.    Keys  7  and  9  Press  simultaneously. Observe    that    number    of    TACAN station    being    used    for    navigation flashes    on    and    off    in    TO-FROM display    and    data    displays    indicate coordinates    of    station    selected    by thumbwheel. 3.  Thumbwheel Set to number of station to be loaded.  Confirm thumbwheel is in detent. 4.  Station 0 cannot be loaded. Observe   that   if   number   of   station   to   be   loaded   is same as number of the TACAN  station currently being used, number in-TO-FROM display will be set to 0 when TACAN data is loaded. 5.  To load zone and easting Press keys in sequence, starting with E. Example: Zone 16, 425 km East =E16 425. Observe  that  zone  and  easting  in  kilometers  appear in the right display as keys are pressed. 6.        INSERT/ADVANCE    pushbutton    - Press. Observe that pushbutton annunciator is illuminated. 7.        To    load    northing    Press    keys    in sequence,   starting   with   N   or   S   to indicate north or south hemisphere. Example:    4749  km  North  =  N  4749.    Observe  that northing  kilometers  appear  in  left  data  display  as  keys are pressed. 8.        INSERT/ADVANCE    pushbutton    - Press. Observe pushbutton annunciator remains illuminated. 9.        INSERT/ADVANCE    pushbutton    - Press. Observe  that  extra  precision  display  related  to  the resident value of northing and easting, to nearest meter, appears in left and[ right data displays, respectively. NOTE UTM  data may be loaded in any order. Until   final   fourth   entry,   actuation   of INSERT/ADVANCE pushbutton without  a  prior  data  entry  'will  cause normal  and  extra  precision  UTM  data to be alternately displayed. 10.  To load extra precision easting value Press keys in sequence, starting with E. Example:  297 m East = E 297.  Observe that easting meters appear in right data display as keys are pressed. 11.      INSERT/ADVANCE      pushbutton   - Press. Observe pushbutton remains illuminated. 12.      To   load   extra   precision   northing value Press keys in sequence, starting with N or S. Example:    901  m    North  =  N    901.    Observe  that northing meters appear in left data display as keys are pressed.    The  value  is  always  added  to  normal  value regardless   of   which   key   (N/S)   is   pressed   to   initiate entry.  The normal entry establishes hemisphere. 13.        INSERT/ADVANCE    pushbutton    - Press. Observe   that   during   the   next   I   to   3   seconds,   the computer  converts  input  into  latitude  and  longitude  for storage    in    memory.        The    stored    value    is    again converted  back  to  UTM    for  display  to  operator.    The INSERT/ADVANCE pushbutton annunciator extinguishes.  The conversion routines may cause data displays to change by up to 10 m. NOTE · The computer will convert coordinates in overlap area; however,  data  display  values  will reference appropriate zone. · The W key may be used to initiate easting entries; however, the computer will 3-52