This program is a very simple tool used to predict when satellites are visible to a certain location. It is based on PLAN13 by James Miller (G3RUH) and is provided as is. It is written in C (my first attempt) and is not optimized for anything. I am sure there are better ways to do some of the things in here but this is pretty bullet proof and does what I want. Currently I am using Borland Turbo C++ 3.0 on my PC to compile it and the GNU gcc-2.4.5 compiler on a SUN workstation. There are a minimum set of data files required for STP to run. 1) myqth.dat ASCII file with the coordinates of the station format: Station name (any string) Latitude (degrees) Longitude (degrees. Negative west of Greenwich) Altitude (meters) table of minimum look angles (input as a function of azimuth) EXAMPLE: (neighbors house in the way between 190-194 degrees azimuth) azimuth minimum angle 0 2 45 5 90 7 135 3 180 0 190 15 191 18 192 35 193 12 194 6 225 6 270 8 315 5 360 2 NOTE #1: If you only input 1 (one) line of values (azimuth and minimum angle) the code will use this for all azimuths. NOTE #2: If you have input a table and want to turn it off temporarily, just change the first minimum angle to be a value less than zero (e.g. -0.10) NOTE #3: Currently put azimuth values in from 0 to 360. Eventually it will work with plus/minus values. Code linearly interpolates between values. Maximum of 360 input values STP will ask for all the data to write to this file the first time it is run or you can use any text editor to create it. 2) nasa.dat or kepler.dat ASCII file with satellite elements. format: nasa.dat Standard NASA 2 Line orbital element file kepler.dat Orbital info in text format NOTE: Currently only 50 (DOS) and 300 (UNIX) satellites and can be loaded at any one time. NOTE: STP currently looks for nasa.dat first. If it is found then the orbital info is taken from it. If you only want to use the kepler type of format only have kepler.dat in the current directory. 3) stp.ini Control flags and information used to compute signal strengths. format: 15.0 FindStep (minutes) initial step size in finding aos/los 1.0 FindAngleError (degrees) if within this angle quit 0.1 FindStepMinimum (minutes) minimum step size 0 plot flag 0-none 1-yes 0 0-360 (0) 1 -180 to 180 1 ground trace 0 - write altitude to plot file 1 write 0.0 145.9 2400.0 Frequency Mode B Mode S (MHz) 2300.0 5000.0 Receiver Bandwidth Mode B Mode S (Hz) 17.0 24.0 Receiver Antenna Gain Mode B Mode S (dBi) 60.0 100.0 Receiver Noise Temperature (Deg Kelvin) 30.0 Average number of users (adjusts downlink power) FindStep is an initial step size used in finding AOS/LOS. If you have a fast computer (>30Mhz 486) or you have alot of patience you can decrease this value to get slightly better answers. FindAngleError and FindStepMinimum determine the "accuracy" to which the AOS/LOS times are determined. plot flag is used to turn on/off the output of a set of data files that can be plotted using a user supplied routine. 360 +-180 flag determines how azimuth values are written out. ground trace flag is used in conjunction with the plot flag to determine if the true altitude of the satellite is included in the plot file or if a zero is written. The next set of lines are used to define the parameters for estimating the downlink signal strength. Optional Data files: 1) mode.dat ASCII file with operating modes of satellites. If no mode.dat file is found or a satellite in nasa/kepler.dat is not defined the mode defaults to "???". format: satellite: satname1 beacon frequency (Mhz) blon blat schedule schedule schedule satellite: satname2 beacon frequency (Mhz) blon blat schedule etc... as few or as many satellites as you want The schedule is entered in terms of Mean Anomaly. Mean Anomaly describes the position of a satellite in its orbit. In tracking programs Mean Anomaly is an angle that goes between 0 and 360 degrees. For scheduling purposes it is useful to specify MA in units of 256 of a circle. Perigee (lowest point on orbit) is at MA 0 degrees and 0/256. Apogee (highest point) is at MA 180 degrees and 128/256. For example ao-13 has the following schedule (March 9,1994) From MA 0 to MA 30 Mode B omni antennas From MA 30 to MA 90 Mode B high gain antennas From MA 90 to MA 120 Mode BS high gain antennas From MA 120 to MA 145 Mode S high gain antennas From MA 145 to MA 150 S beacon only From MA 150 to MA 180 Mode BS high gain antennas from MA 180 to MA 230 Mode B high gain antennas From MA 230 to MA 256 Mode B omni antennas This schedule would be entered as; 000030Bom 030090B.. 090120BS. 120145S.. 145150Sbc 150180BS. 180230B.. 230256Bom Simplier schedules can also be entered. For example for AO-10 000256B.. STP uses the mode names of Bom or BS. or S.. to perform some simple received signal calculations and to modify the squint calculation between the omnidirectional and high gain antennas. The beacon frequency is used to compute the doppler shift. Blat and Blon refer to the pointing angles the antennas on the satellite make with the earth. For example if Blon=180 and Blat=0 then when the satellite is at apogee the antennas are pointing directly at the surface of the earth. These values are only important for high altitude satellites like AO-13, AO-10 or ARSENE (which is dead as of this writing (October 31,1994)). These angles are used to compute the squint angle that the antennas make with your QTH. At high squint angles (30-50 degrees) the signals get weak and due to the spin of the satellite the signals are modulated. See the included mode.dat file as an example. 2) revcor.dat ASCII file containing information relating to the correct revolution data. The elements that are normally used have a relative revolution number that changes at the beginning of each year. Sometimes it is valuable to know what the correct revolution number is. This file allows the user to include a factor that corrects the data in the element file. format: satellite name correction factor 3) qth.dat ASCII file containing information relating to mutual visibility calculations. Sometimes you want to know when a mutual window will exist between your location and some other location (e.g. chasing DX or working a friend on vacation). The file qth.dat contains the latitude,longitude, altitude and name for these other locations. To select a location or locations the user edits the file and places the following command words around the cities of interest. starthere city1 city2 city3 stophere Every city between starthere and stophere will be include in the calculation of mutual visibility. Currently the limit is 90 cities at any one time. Lack of Features: This code will NOT drive any rotors as of yet. It also does not have any fancy graphics as of yet. I work on the code mainly as a learning experience and as a practical means to operating the satellites without a computer controlled rotor system so there is no fixed set of releases or future plans. NOTES on compiling: If you have obtained the source code for STP then you will need to make some minor modifications. If you are operating on a UNIX based platform then insure that the following statement exists in stp.c #define UNIX also make sure that the path statements in stp.unx agree with the location of the datafiles. On a DOS platform: #define MSDOS and set the paths in stp.dos. NOTE that 2 (two) backslashes are required in the pathname. C uses \ as indication of a special character and if you want to use a \ then you must use two \\ (first slash says use next item as a character and not a special character). With Borland Turbo C++ 3.0 I use to following command (on a 486 with 8Mb); tcc -O1 -O2 -ml stp Makefile for GNU C # Makefile CFLAGS = PROGRAM= stp HEADERS= stp.unx SOURCES= stp.c bioskey.c OBJECTS= stp.o bioskey.o MAKEFILE= Makefile LIBS= -lm CC= gcc all: $(PROGRAM) $(PROGRAM): $(OBJECTS) $(CC) $(CFLAGS) -o $(PROGRAM) $(OBJECTS) $(LIBS) Useage: In the following discussion means press the return key. STP is run from the command line. if you just type STP you will get a listing of the currently available commands and some acknowledgements. NOTE: the options are case sensitive (e.g. r and R are different options). a....AOS/LOS times (relative time) A....AOS/LOS times (absolute time) c....Sun/Moon real time display C....Perform Check Sum calculations on 2-line nasa file (can put filename on command line... STP C nasa.dat) d....Dump information about satellites (beacon freq, alat,alon, # of modes) e....View/Edit orbital parameters h....Simple suggestions m....Mutual visibility calculation M....Real Time Mutual visibility. Use the following to add observers g-add based on grid locator l-add based on lat,lon,alt o-add based on names in qth.dat p....Prediction for a single satellite r....Real-time table of currently visible satellites, additional parameter after r is update rate in seconds (default is 1 second) R....Real-time table of all satellites, additional parameter after R is update rate in seconds (default is 1 second) s....Same as option R but uses a selected set of satellites S....Selects satellites for option s The first time you run STP it will ask you for information about your qth, unless you have created myqth.dat prior to execution. After you finish inputting the info the above table will appear. After this first time any time you enter STP the above table will print on the screen. OPTION a: This option loops over all satellites in the data file and determines the RELATIVE time to acquisition of the satellite (elevation > 0.0) and loss of the satellite. If the satellite rise time is greater than 2 days in the future that a message is printed to that affect. The format of the time is days:hours:minutes:seconds You will note that some satellites show no AOS/LOS times. These satellites are judged to be in a geostationary orbit by STP and are either constantly in view or out of view. If the satellite is currently in view then Dt AOS is shown as 00:00:00. The following is an EXAMPLE; Sat AOS LOS AO13sm 00:07:01:44 00:08:16:07 OSCAR10 00:03:18:07 00:10:40:18 UOSAT2 00:02:21:28 00:00:09:39 MIR 00:00:56:19 00:00:10:25 RS-10/11 00:00:46:08 00:00:12:13 AO-13 00:07:01:01 00:08:16:02 UO-14 00:06:52:44 00:00:08:39 UO-15 00:06:52:50 00:00:09:20 DO-17 00:06:42:48 00:00:04:54 WO-18 00:07:45:31 00:00:13:11 LO-19 00:07:04:03 00:00:09:04 FO-20 00:00:21:47 00:00:40:48 AO-21 00:08:35:43 00:00:11:31 RS-12/13 00:00:40:01 00:00:16:03 UO-22 00:06:54:24 00:00:12:56 KO-23 00:06:17:54 00:00:18:12 ARSENE 01:03:02:55 00:18:43:03 AO-27 00:07:08:16 00:00:13:29 ITAMSAT 00:06:02:20 00:00:05:18 KO-25 00:06:01:06 00:00:08:31 1994067B Rise/Set Time > 2 Days from now!! 1994067C Rise/Set Time > 2 Days from now!! OPTION A: Same as above except shows actual times instead of RELATIVE. EXAMPLE: Sat Day AOS Day LOS AO13sm Tuesday 02:41:51 Tuesday 10:57:53 OSCAR10 Monday 22:58:07 Tuesday 09:38:31 UOSAT2 Monday 22:01:32 Monday 22:11:12 MIR Monday 20:36:20 Monday 20:46:44 RS-10/11 Monday 20:26:12 Monday 20:38:25 AO-13 Tuesday 02:41:02 Tuesday 10:57:05 UO-14 Tuesday 02:32:47 Tuesday 02:41:27 UO-15 Tuesday 02:32:54 Tuesday 02:42:15 DO-17 Tuesday 02:22:52 Tuesday 02:27:46 WO-18 Tuesday 03:25:36 Tuesday 03:38:42 LO-19 Tuesday 02:44:07 Tuesday 02:53:11 FO-20 Monday 20:01:50 Monday 20:38:21 AO-21 Tuesday 04:15:46 Tuesday 04:27:17 RS-12/13 Monday 20:20:05 Monday 20:36:08 UO-22 Tuesday 02:34:27 Tuesday 02:47:18 KO-23 Tuesday 01:57:58 Tuesday 02:16:05 ARSENE Tuesday 22:42:53 Wednesday 17:26:02 AO-27 Tuesday 02:48:20 Tuesday 03:01:50 ITAMSAT Tuesday 01:42:21 Tuesday 01:47:40 KO-25 Tuesday 01:41:06 Tuesday 01:49:38 OPTION c: Provides a realtime display of the sun/moon azimuth,elevation and range. Additional parameter on command line is update rate in seconds. Screen capture of option c; 19:42:40 Sun : 218.69 31.83 151535606.370 Moon: 256.33 12.62 366631.759 format is Azimuth (degrees) Elevation (degrees) Range (Km) OPTION C: Perform checksum calculation on nasa 2 line file. useage: stp C Outputs corrected file to newnasa.dat. If the user fails to enter a name on the command line STP will prompt for one. OPTION d: This option dumps out some basic information about the satellites as entered through nasa.dat or kepler.dat and mode.dat. EXAMPLE: # Beacon Alon Alat Apogee Perigee Period Ecc Age Mhz deg deg Km Km min days 8 145.8120 230 0 38016.1 790.6 719.2 0.72194 82.81 AO13sm 1 145.8120 209 -17 35451.1 3994.6 732.6 0.60259 14.50 OSCAR10 1 435.0250 0 0 671.1 655.7 102.7 0.00109 6.44 UOSAT2 1 145.5500 0 0 396.2 393.2 96.8 0.00022 5.19 MIR 1 29.3570 0 0 1000.5 981.9 109.9 0.00126 7.19 RS-10/11 8 145.8120 230 0 38072.2 733.2 719.2 0.72416 4.12 AO-13 1 435.0700 0 0 800.0 784.4 105.5 0.00109 6.75 UO-14 1 435.1200 0 0 801.6 787.3 105.5 0.00100 6.25 UO-15 1 145.8250 0 0 799.7 783.4 105.5 0.00114 6.25 DO-17 1 437.0751 0 0 800.1 783.2 105.5 0.00118 6.25 WO-18 1 437.1530 0 0 800.1 782.5 105.5 0.00123 7.31 LO-19 1 435.7970 0 0 1745.7 911.3 117.5 0.05413 6.69 FO-20 1 145.9870 0 0 1010.5 956.1 109.7 0.00370 4.62 AO-21 1 29.4080 0 0 1007.7 962.5 109.8 0.00307 7.06 RS-12/13 1 435.1200 0 0 773.5 763.7 105.0 0.00069 6.75 UO-22 1 437.1750 0 0 1328.1 1304.5 117.3 0.00153 5.75 KO-23 1 2447.0001 120 0 36748.1 17303.1 1060.7 0.29106 8.25 ARSENE 1 436.8000 0 0 805.6 793.7 105.7 0.00083 5.75 AO-27 0 145.0000 0 0 805.3 791.0 105.6 0.00100 5.81 ITAMSAT 1 436.5000 0 0 805.5 790.9 105.6 0.00102 7.25 KO-25 If any mode data is set in modes.dat then # is how many modes it found. Beacon frequency in Mhz, Alon/Alat are satellite pointing angles (sometimes called Blon and Blat), Apogee is apogee altitude in Km, Perigee is perigee altitude in Km, Period is orbital period in minutes, Ecc is orbit eccentricity (0 is perfect circular), Age is the age of the element set and finally the satellite name. This table is just a quick way to check the input data. OPTION e: Allows the user to edit/view the orbital parmeters for each satellite loaded. Edits which ever type of file STP is started with (nasa 2 line or kepler format). For the kepler format a new file named kepler.tmp is created. For the nasa 2 line format nasa.tmp is created. To utilize the modified database you must rename kepler.tmp to kepler.dat or nasa.tmp to nasa.dat (see discussion of nasa/kepler.dat). OPTION m: This option allows you to determine the mutual visibility between your qth and some other location. The included file qth.dat contains some of the more popular qth locations as well as some major cities. To use this option you must edit the datafile and place the keywords starthere and stophere around the city or cites that you are interested in. You can also just create a datafile with then information you want in it. Once you have done that then you issue the following; 1) STP m satellite name (if you know which satellite you want) or 2) STP then asks you for additional informtion Enter Start Day (month day year): Number of Days for Prediction: Step Size (minutes....input negative value for seconds): FileName to write output to (cr for screen): Suggestions/Formats on inputs: Start Day (format) Months 1-12 Days 1-31 Year 199?-??? Number of Days 1 or more. You can input as big a value as you want but remember that for LEO type satellites (RS-10/11, AO-21,...) the elements change due to drag and predictions longer than a month will start to show errors. Step Size (minutes....input negative value for seconds): 5 is good for AO-13,AO-10 and other high altitude/Molynia type satellites. Use 1 for RS-10/11, AO-21, or other LEO satellites. If the step size is input as negative then STP assumes the time is in seconds and adjusts the output accordingly. FileName If you press at FileName prompt then the run is output to the screen, If you enter a filename the output is written to the filename specified. The following example is looking for mutual visibility between KD4QIO and Stanley, Falkland Islands and Peter I using AO-13. The left half of the table is the local information and the right half is for the other location(s). The information is provided as a function of UTC. Az azimuth of satellite (degrees), home QTH EL elevation of satellite (degrees), home QTH Range range from home QTH to satellite (Km) Sqnt "squint" angle (degrees) as viewed from home QTH Az azimuth of satellite (degrees), mutual site EL elevation of satellite (degrees), mutual site Range range from mutal site to satellite (Km) Sqnt "squint" angle (degrees) as viewed from mutual site Mde mode the satellite is operating in The last column is the site name (only usefull if more than one site selected) ---------------------------------------------------------------------- Prediction Date : Monday October 31 1994 Amsat Day: 6147 Prediction For : 2 Sites Performed on : October 31 1994 13:54:09 Satellite : AO-13 (Set: 988, Rev #: 5966, Age: 4.1 Days) Illumination : 86.4% SAZ/SEL 350.5/-1.3 AP/RAAN 353.6/222.8 Alon/Alat : 230.0/ 0.0 Frequency: 145.8120 MHz ---------------------------------------------------------------------- Local | Dx UTC Az El Range Sqnt | Az El Range Sqnt MA Mde ---------------------------------------------------------------------- 0855 249 31 40803 51 | 316 0 43906 60 122.7 OFF Peter I 0900 250 30 40933 51 | 315 0 43908 59 124.6 OFF Peter I . . 1040 253 7 40969 39 | 294 5 41239 47 161.9 B.. Peter I . . 1105 254 2 40159 35 | 288 6 39706 44 171.2 B.. Peter I 1110 254 0 39953 35 | 287 6 39353 43 173.1 B.. Peter I ---------------------------------------------------------------------- Prediction Date : Tuesday November 01 1994 Amsat Day: 6148 Prediction For : 2 Sites Performed on : October 31 1994 13:54:09 Satellite : AO-13 (Set: 988, Rev #: 5968, Age: 4.1 Days) Illumination : 86.2% SAZ/SEL 350.7/-2.3 AP/RAAN 353.7/222.7 Alon/Alat : 230.0/ 0.0 Frequency: 145.8120 MHz ---------------------------------------------------------------------- Local | Dx UTC Az El Range Sqnt | Az El Range Sqnt MA Mde ---------------------------------------------------------------------- 0540 216 71 32866 68 | 324 0 38374 78 74.9 OFF Stanley 0545 217 70 33294 67 | 323 1 38729 77 76.8 OFF Stanley . . 0700 229 54 38123 56 | 308 4 42534 66 104.8 OFF Stanley 0705 230 53 38347 56 | 307 4 42690 65 106.6 OFF Stanley 0705 230 53 38347 56 | 340 0 43077 65 106.6 OFF Peter I 0710 230 51 38559 55 | 305 4 42834 65 108.5 OFF Stanley 0710 230 51 38559 55 | 339 1 43175 64 108.5 OFF Peter I . . 1035 244 5 36958 30 | 296 13 36131 39 184.9 B.. Peter I 1040 244 4 36634 29 | 295 13 35649 38 186.8 B.. Peter I . . 1050 243 2 35940 27 | 293 14 34631 36 190.5 BS. Peter I 1055 243 0 35566 27 | 292 14 34093 36 192.4 BS. Peter I OPTION M: Realtime display of mutual visibility. Useage: stp M Once this mode is operational additional sites can be added by pressing; g-add based on grid locator (e.g. fn13ed) l-add based on lat,lon,alt (-68.783 -90.583 0) o-add based on names in qth.dat (beijing or om89ew or china) case independent To stop this mode press q. OPTION p: This option generates a table that allows the user to predict when the satellite will be in view of the local QTH. You can start this option in two ways; 1) STP p satellite name (if you know which satellite you want) or 2) STP p (and STP will show you a list of the available satellites) After selecting the satellite STP will want the following information: Enter Start Day (month day year) ( for current date): Number of Days for Prediction: Step Size (minutes....input negative value for seconds): FileName to write output to (cr for screen): Suggestions/Formats on inputs: Start Day format Months 1-12 Days 1-31 Year 199?-??? Number of Days 1 or more. You can input as big a value as you want but remember that for LEO type satellites (RS-10/11, AO-21,...) the elements change due to drag and predictions longer than a month will start to show errors. Step Size (minutes....input negative value for seconds): 5 is good for AO-13, AO-10 and other high altitude/Molynia type satellites. Use 1 for RS-10/11, AO-21, or other LEO satellites. If the step size is input as negative then STP assumes the time is in seconds and adjusts the output accordingly. FileName If you press at FileName prompt then the run is output to the screen, If you enter a filename the output is written to the filename specified. EXAMPLE (prediction for ao-13 ) The header block provides the UTC date for the prediction, the current revolution (REV) counter and the AMSAT day. Also provided are the satellite chosen, the sun illumination and the azimuth and elevation the sun makes with the satellites (SAZ/SEL) solar panels, the starting Argument of Perigee and the R.A.A.N (AP/RAAN). The current pointing angle information (ALAT/ALON) is shown along with the frequency used to compute the doppler shift. The format of the table is: UTC UTC time for prediciton Az Azimuth of satellite (degrees) El Elevation of satellite (degrees) Range Range from QTH to satellite (Km) Sqnt Squint angle as viewed by QTH (degrees) (for ao-13 corrections are made based on if the high gain on omni directional antennas are in use) Dopplr Doppler shift (Hz) (for ao-13 the beacon frequency will shift for Mode S) MA Mean Anomaly (0-256) Mode Operation Mode Sun contains either a -,+,vis or ECL which indicate the following: + shadow side of earth (high probability of being sunlit) - sunny side (definitely sunlit) vis possibily in view of observer (sun below 10 degrees elevation) ECL eclipsed by earth (definitely not sunlit) The data in the last one or two columns is only computed if AO-13 or AO-10 is the chosen satellite. STP performs a relative signal calculation based on the orientation of the satellite, the range from the satellite to the observer and the gain of the satellite transmitter. These values are used only to provide an indication of the received signal strength (your milage may vary). If AO-13 is in mode BS then calculations for both Mode B and Mode S are shown. If only Mode B or Mode S then only calculations for that mode are shown. When AO-13 is operating either the Mode S beacon (Sbc) or Mode S only (S..) the doppler shift is computed assuming a beacon frequency of 2400.375 Mhz. For all other modes for AO-13 the beacon frequency is 145.812 Mhz. Changing the values in mode.dat WILL NOT alter these calculations for AO-13 (must modify the source code). Anytime the revolution number or the date changes or a gap of more than StepSize appears in the table a new header block is written out. ---------------------------------------------------------------------- Prediction Date : Monday October 31 1994 Amsat Day: 6147 Prediction For : kd4qio at home Performed on : October 31 1994 14:02:57 Satellite : AO-13 (Set: 988, Rev #: 5966, Age: 4.1 Days) Illumination : 86.4% SAZ/SEL 350.5/-1.1 AP/RAAN 353.6/222.9 Alon/Alat : 230.0/ 0.0 Frequency: 145.8120 MHz ---------------------------------------------------------------------- UTC Az El Range Sqnt Dopplr MA Mode Sun PRSL ---------------------------------------------------------------------- 0355 319 9 9681 79 -470 10.9 Bom vis 26.65 0400 320 20 10082 68 -811 12.8 Bom vis 26.60 . . 0445 309 67 17428 15 -1409 29.5 Bom vis 22.25 0450 305 68 18290 102 -1385 31.4 OFF vis 0455 301 70 19136 99 -1358 33.3 OFF vis . . 0705 246 55 34917 66 -657 81.7 OFF vis 0710 246 54 35316 65 -635 83.6 OFF ECL 0715 246 53 35700 64 -614 85.5 OFF ECL . . 0830 248 36 39977 54 -316 113.4 OFF ECL 0835 248 35 40166 54 -297 115.3 OFF vis . . 1005 252 15 41531 43 +56 148.8 OFF vis 1010 252 14 41488 42 +76 150.7 B.. vis 24.81 . . 1110 254 0 39953 35 +346 173.1 B.. vis 25.82 ---------------------------------------------------------------------- Prediction Date : Tuesday November 01 1994 Amsat Day: 6148 Prediction For : kd4qio at home Performed on : October 31 1994 14:02:57 Satellite : AO-13 (Set: 988, Rev #: 5968, Age: 4.1 Days) Illumination : 86.2% SAZ/SEL 350.7/-2.1 AP/RAAN 353.7/222.7 Alon/Alat : 230.0/ 0.0 Frequency: 145.8120 MHz ---------------------------------------------------------------------- UTC Az El Range Sqnt Dopplr MA Mode Sun PRSL ---------------------------------------------------------------------- 0245 317 11 8586 80 -305 9.7 Bom vis 27.65 . . 1030 244 6 37264 30 +483 183.1 B.. vis 26.75 1035 244 5 36958 30 +509 184.9 B.. vis 26.87 1040 244 4 36634 29 +536 186.8 B.. vis 26.99 1045 244 3 36295 28 +564 188.7 B.. vis 27.12 1050 243 2 35940 27 +591 190.5 BS. vis 27.25 27.70 1055 243 0 35566 27 +620 192.4 BS. vis 27.38 28.14 OPTION r: This option performs a real-time (limited by you cpu speed) prediction of satellites currently visible from the home QTH. Only satellites that are in view (Elevation > 0.0) are shown. The following is a screen capture of STP r: LOC Sunday November 06 1994 14:47:42 GMT Sunday November 06 1994 20:47:42 Az El Range Squnt Doppler MA Mode Sun 49 9 v 19371 2 -1867 25.6 Bom + AO13sm 122 35 v 28890 60 -736 60.3 B.. - OSCAR10 49 8 v 19558 3 -1860 25.7 Bom + AO-13 248 19 ^ 25098 159 +10406 226.7 xxx - ARSENE If no mode data has been set then ??? is displayed. An additional parameter can be specified on the command line at execution time. This parameter is the update rate in seconds. With no parameter specified the default is 1 second. To specify a rate of 5 seconds you would enter; STP r 5 If you want to see relatively how fast your computer is enter; STP r 0 and watch the seconds block of the LOC entry. If your screen is flashing several times prior to the seconds block updating then you are able to update the information several times a second. If your screen does not flash between updates then the time difference shown in the LOC block is the slowest rate that you should try to run this option at. For example on an 8086 the seconds block updated at about once every 7 seconds. On this machine the following would be used; STP r 10 OPTION R: Identical to OPTION r except that all the satellites are shown. The format of the display is changed to indicate if the satellite is in view or not and the RELATIVE time to AOS/LOS. The following is a screen capture of STP R: LOC Monday October 31 1994 14:06:48 GMT Monday October 31 1994 20:06:48 Az El Range Squnt Doppler MA Mode Sun Status AOS--LOS 47 -40 v 48039 47 -106 117.0 OFF + aos 06:35:01 AO13sm 40 -27 ^ 30562 26 +967 210.9 B.. + aos 02:51:20 OSCAR10 134 -44 ^ 9743 41 +5884 94.6 PKT + aos 01:54:45 UOSAT2 229 -64 ^ 11893 24 +1476 63.1 PKT - aos 00:29:31 MIR 203 -39 ^ 9437 42 +451 215.8 A.. - aos 00:19:26 RS-10/11 47 -40 v 48113 47 -103 117.2 OFF + aos 06:34:17 AO-13 8 -17 ^ 5706 58 +6827 216.3 FSK + aos 06:26:02 UO-14 9 -18 ^ 5804 58 +6759 212.9 TLE + aos 06:26:02 UO-15 302 -3 v 3580 63 -414 247.6 PKT - aos 06:16:05 DO-17 203 -54 v 11307 31 -4876 72.6 PKT - aos 07:18:46 WO-18 34 -38 ^ 9116 44 +6812 186.5 PSK ECL aos 06:37:18 LO-19 16 24 ^ 2509 49 +7522 65.5 JA. - -LOS- 00:17:55 FO-20 296 -2 ^ 3892 60 +359 52.6 DIG - aos 08:08:54 AO-21 172 -31 ^ 8224 48 +516 167.0 K.. - aos 00:13:17 RS-12/13 28 -27 ^ 7341 52 +6554 127.9 PKT ECL aos 06:27:39 UO-22 132 -47 ^ 11024 34 +491 42.8 FSK + aos 05:51:09 KO-23 14 -60 v 44545 20 -5573 80.1 S.. + aos 26:36:02 ARSENE 54 -47 ^ 10368 37 +5581 155.2 FM. ECL aos 06:41:33 AO-27 175 -67 v 12621 20 -613 91.0 --- - aos 05:35:30 ITAMSAT 178 -66 v 12532 21 -1832 101.1 FSK - aos 05:34:21 KO-25 The column after the elevation (El) has either a ^ to indicate the satellite is approaching or a v to indicate going away. The column after Mode contains either a +,-,vis or ECL showing the sun illumination on the satellite. The next column will contain either aos or -LOS- indicating if the time in the AOS--LOS column is time to acquisition of signal (aos) or loss of signal (los). The next column is the RELATIVE time (hours:minutes:seconds) until AOS/LOS. OPTION s: Similar to OPTION R except that only a selected set of satellites are shown. OPTION S: Used to select the satellites for OPTION s. Creates a file called select.dat Plug: I would suggest that you join AMSAT and buy one of their codes if you are interested in automating the tracking process (Instanttrack is sort of a standard). There are other codes available (RealTrack, Sattrack, etc.) each of which do something a little different. Other tools; WISP. SatSked. Plea: If you use the code and find problems, have suggestions for additions or know better/faster ways to perform the same job please let me know. Future efforts: Break the code up to make it more managable. Rewrite the rise/set algorithm using the work of Escobal (same algorithm used in most of the famous programs). Rotor Control. Graphics/Windows Acknowlegdements: I am very grateful to James Miller (G3RUH) for providing me a copy of his PLAN13 paper and answering the stupid questions that I have come up with over time. I would also like to thank Mark Phillips (N2RPZ) for helping me debug this code and provide suggestions. I would also like to thank some of my predicessors; Robert W. Berger (N3EMO) the author of Orbit. The methodology for reading the nasa format database came from N3EMO's code. Manfred Bester (DL5KR) the author of SatTrack. The initial qth.dat file came from the distribution tape of SatTrack. Both of these authors have developed and provided very useful tools. Internet: harper@huntsville.sparta.com or kd4qio@amsat.org Packet: kd4qio@k4bft.#hsv.al.usa.na Work: (205) 837-5282 x1216 Snail Mail: Christie Harper P.O. Box 18786 Huntsville, Al 35804 73's and look forward to talking to you on the satellite.