HAM Radio 1/HamRadio.cdr/satel/sat/satellit.doc

Text File | 1992-03-26 | 16KB | 392 lines

                        SATELLITE TRACKING PROGRAMS
                               FOR THE IBM-PC
                                  4/1/85


                      *****  PROPRIETARY NOTICE *****

These programs  are a proprietary product developed and distributed by Roy D.
Welch, 908 Dutch Mill Dr., Manchester, Mo. 63011.

Copyright 1983 by Roy  D. Welch.  All rights  reserved except those expressly
granted  to the user within  this document.  Permission  is granted  for  non-
commercial use providing credit is given to the author and AMSAT.


                          ***** REQUIREMENTS *****

                       IBM-PC or IBM-PCXT
               128k of RAM
            IBM Color Graphics Adapter
            IBM Color Monitor
            Floppy Disk Drive (one)
            DOS 2.0 or later version with BASICA



                             ***** GENERAL *****


This  documentation  covers  the  instructions needed  for  using the  various
associated  programs  on this  diskette  as  described below.  These  programs
permit the user to establish  data records for  up to twenty  earth satellites
and to track  those satellites  for the  purpose of  aiming radio  antennas at
them.  The user can select a particular program from  a menu and  that program
will be loaded and  executed automatically.  As  written, the programs require
the use of an IBM Color Graphics Adapter. However, only one program absolutely
requires  it.  The other programs  can  be run  using a monochrome monitor  by
eliminating the COLOR commands  and modifying the  SCREEN commands  where they
appear in those programs.

The programs are  written to be run on an  IBM-PC.  Most of the  programs will
run on a system with 64k of RAM memory.  The realtime tracking program however
requires 128k  because  map graphics data is stored in  high  memory  where it
is available to be moved to the display buffer.  The  programs are  written in
Microsoft BASIC and run under DOS 2.0 or later.  While the programs may run on
the so called "IBM compatibles", there is no assurance of compatibility.

Before the programs can be run the user must supply some information unique to
his own geographical  location  and  ground station.  This  will be  described
later. He must also have  a source of satellite  orbital elements in  order to
periodically update the "numbers".  This too will be discussed later.

It is strongly suggested that at this point the user make a backup copy of the
program  diskette PRIOR  to  making any  program  modifications.  Later, after
program modifications have been made,  a working  copy diskette can  be copied
with your unique station modifications on it.  See ADDITIONAL COMMENTS.


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                           ***** SATMENU.BAS *****


This program  should be the first one run.  It provides a menu  from which the
user can  select one of  five  other programs for use.  Each of these programs
provide a way to return to the menu when desired.  Of these five programs, one
provides batch output  for a single satellite, listing tracking information in
non-realtime  for a selected  time  period.  A  second  program  provides  the
capability for realtime tracking.  The third is a file management program that
provides the capability for updating  the orbital elements for each satellite.
A fourth program gives instructions for obtaining this documentation.  A final
program  provides a means  for the user to  install parameters  concerning the
particular  ground  station  being used such as  latitude, longitude, altitude
above sea level and station name or call sign.   This program  also allows the
user to select one of four map presentations and its color.  The world map can
be constructed such that the center of the map on the  screen can be at 0, 90,
180, or 270 degrees longitude to suit the user.




                           ***** SATFILE.BAS *****


This  program is  a  file  management routine  that  builds  and  maintains an
orbital elements file used by the tracking programs.  It will  handle elements
for up to twenty satellites.  Only the  first eight will  be used in the real-
time tracking program however.  The file should be arranged with this in mind.
SATFILE.BAS can be accessed from the menu discussed above.  Prompting  is used
extensively to guide the user through adding, changing  and deleting satellite
elements.  The user must also supply a name or designation for each satellite.
This name must not exceed ten characters and must consist of  alphabetical and
numerical  characters only.  Provision  is made to  input a  beacon  frequency
for a  satellite if  Doppler  Shift  calculations  are  desired.  This is  not
required however and is not  used in  the real  time tracking  program.  These
required orbital elements are the classical Keplerian Orbital Elements and are
available from NASA or through a subscription to the  Amateur Satellite Report
(ASR).  If you get them from  NASA you will get a large volume of paper, often
two or three times a week.


            1. Write to  NASA Predictions Bulletin Oprns. Ctr.
               Branch code 512, NASA GSFC
               Greenbelt, MD 20771

            2. State, "I am a Radio Amateur operator and need prediction
               bulletins for these satellites", or something similar.

            3. Furnish a list of desired satellites by catalog number:

                  OSCAR 10 = 14129
                  OSCAR 11 = 14781
                       RS5 = 12999
                       RS6 = 13002
                       RS7 = 13001
                       RS8 = 12998

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            4. Also request the format explanation for these bulletins.

            5. Be prepared to get a lot of mail!!


The Amateur Satellite Report is published and mailed First Class bi-weekly for
the Radio Amateur  Satellite Corporation.  Subscriptions  may  be obtained  by
writing to "Satellite Report",  221 Long Swamp Road,  Wolcott, CT  06716.  The
advantage of obtaining updates from ASR is that the user also gets a fine news
letter in addition to timely element updates.  Also, there is a lot less paper
to be handled that way.

The program SATFILE.BAS stores  the satellite  elements in  a data  file named
ELEMENTS.DAT on the same diskette  containing the programs.  When elements are
updated  the diskette must not have a  file protect tab affixed.  The sequence
of appearance in the file can be changed through the option of inserting a new
satellite in any of the occupied  file  positions.  This insert feature allows
the user to  arrange the  first eight  positions with the  satellites he wants
tracked by the real time program.

The SATFILE.BAS program eliminates the need for using DATA  statements in both
of the tracking  programs.  This saves  duplicative  effort when  updating the
elements. One update serves both programs.

If for some reason it  is desirable  to see fewer  than the maximum  number of
satellites available to the realtime tracking  program, the user  can insert a
dummy satellite named END at the position following the last satellite wanted.
The program  will only  load satellite elements until  it finds the  one named
END.

At the  conclusion of an  update, the user  can select  an exit  option  which
returns control to the main menu program.  The user must always exit from this
program  using the  EXIT (E) option.  If  the  program is  exited by any other
method, files may be subsequently damaged since they will not have been closed
properly.


                           ***** ORBIT2.BAS *****


This program is  a  highly modified  version  of the  W3IWI  North Star  Basic
program covered in ORBIT  Magazine, March/April 1981, page 18.  It  provides a
batch output  of  tracking  coordinates  for selected  periods  of  times  and
intervals. This output is available on the screen or printer and is useful for
compiling a sequence of tracking coordinates  on hard copy for later use.

As mentioned above, this program has been  highly  modified from  the original
W3IWI version. Certain coordinates in the original version were initialized at
the beginning of  the run.  This version  updates them  each time  through the
orbit calculation loop.  This eliminates a small but cumulative error from the
output on long runs covering  several orbits.  The original version  used DATA
statements  to  supply  the   orbital  parameters.   This  version   uses  the
ELEMENTS.DAT file as  discussed  earlier.  The  original  version  permitted a
satellite to be tracked  through  January of the  year following the reference



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year contained  in the elements.  This version permits tracking throughout the
entire year  using elements  from  the  previous  year. The  original  program
provided  paging to a new  page with each new orbit.  This  version pages with
each new day instead.  This  seems to provide  a more user oriented output and
consumes less paper.

Once the output has started, depressing the ESC key will interrupt the program
and return  control to the menu  program.  When the  program  has finished, an
END OF JOB message is displayed.  Depressing the ENTER key at this  point will
return control to the menu program.



                           ***** ORBITS2.BAS *****


This program displays tracking coordinates for  up to eight  satellites on the
screen at one time and  updates them  continuously  in real time.  The program
prompts for input of the  date and time in  Coordinated Universal Time  at the
beginning  of the run.  If the  date and time  displayed  is already  correct,
depressing the enter key will allow the program to proceed.

The program makes the F9 function key  available to key trap  the selection of
either of two displays on the screen.  Initially the screen displays  tracking
coordinates in a tabulated format. Pressing the F9 key switches the display to
a Mercator Projection  map of the world upon which each  satellite position is
displayed  and  moved in  realtime.  The coordinates  for each  satellite  are
displayed  below the  map as  that satellite  is updated.  Depressing the  F10
function key allows the user to select a particular  satellite by  designation
(name) and to display  only that satellite's  coordinates  below the map.  The
shape of the  selected  satellite will be  altered for easy  recognition.  All
satellites will continue to be updated on the map but the selected one will be
the only one whose coordinates are displayed below the map. Depressing the F10
key a second time will allow the user to replace  the selected  satellite with
another  or  to  exit from  the  SELECTED  mode  if  the F10 key  is  followed
by  depressing the RETURN  key.  Depressing  the F9 key  again will switch the
display back to the  tabulated  display.  At any time, the ESC key will permit
the user to return to the main menu.  NOTE: The use of more than one  function
key at a time to "key trap" is not  supported  by some "IBM compatibles".  The
use of the F10 key therefore may be ignored by those machines.

Because of the graphics used in  this program the IBM  Color  Graphics Adapter
is required  in the PC.  At the  time the  program is started, a BLOAD command
loads the map image  data into upper  memory from a file named  MAP.DAT on the
diskette.  When the F9 key is depressed  this map image is moved  very rapidly
to the graphics display buffer by a small efficient machine language routine.











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                          ***** SETPARMS.BAS ******


This  program  permits the user to setup his ground station parameters.  While
the programs can be run as they are, they will  produce  output for the QTH of
W0SL.  The user can run them as they are for  demonstration  purposes if he so
wishes.  However, before the  programs will produce  output for the user's QTH
this program must be selected from the menu  and certain  input provided.  The
program will prompt for input  of latitude  (0 to 90 degrees north or 0 to -90
degrees south), longitude (0 to 360 degrees west)  and height  above sea level
(- if below) of the ground station.  Additionally the user is prompted for the
input of the station name or call sign  (10 alphanumeric  characters maximum).
Please note that the latitude and longitude are to be in  decimal degrees, not
degrees, minutes and  seconds.  Following  this the user is  prompted to input
a preference of how the map should be presented, centered on 0, 90, 180 or 270
degrees.  Finally, a choice of  map outline colors is  requested.  The program
then begins to read file LATLONG.DAT and construct the map.  This will  take a
few minutes so the user can get a cup of  coffee or just  watch at this point.
When the map has been constructed, an end of job message  prompts the user for
action which will return him to the menu.  The ground station  parameters will
have been saved in a file named QTH.DAT and the map image will have been saved
in a file named MAP.DAT.  The ground  station parameters will remain in effect
for all subsequent runs of the tracking programs  until the  user decides that
he wants to  change them.  He can do so at  any time by  selecting that option
from the menu.


                             ****** FILES ******


       SETPARMS.BAS              SATFILE.BAS               SATMENU.BAS
       ORBIT2.BAS                ORBITS2.BAS               SATELLIT.DOC
       PRINTDOC.BAS              LATLONG.DAT            #  MAP.DAT
    #  QTH.DAT               ##  ELEMENTS.DAT

       #   These two files are created by SETPARMS.BAS.
       ##  This file is created by SATFILE.BAS.



                       ***** ADDITIONAL COMMENTS *****

If the user wants the  menu program to automatically  load when the  system is
booted the following procedure can be used:


          1. Format a new diskette using the FORMAT/S option  in DOS 2.0  or
             later version.

          2. Copy BASICA.COM from your DOS diskette onto the new diskette.

          3. If the PC is equipped with a realtime clock  (not the PC system
             clock) then copy onto the diskette the software program that sets
             the PC system clock. This is a nice feature but not an absolute
             requirement.


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          4. Copy all  of the programs and  files from the satellite diskette
             to the new diskette using the COPY *.* option in DOS.


          5. Place the new diskette in the default drive.  From DOS enter:

                  COPY CON: AUTOEXEC.BAT  (followed by ENTER key)

                  (Clock program name if used, followed by ENTER key)

                  BASICA SATMENU (followed by ENTER key)

                  (Press the F6 key followed by the ENTER key)

The SATMENU.BAS routine  will now  run  automatically whenever  the system  is
booted on the new diskette.  Have fun!  Don't forget to support AMSAT!!









































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