APRStk.TXT        APRStk Sumary
==========================================================================
Document version: K10
Document dated:   31 Mar (Last update was 17 Mar 00)
Author(s):        Bob Bruninga, WB4APR <bruninga@nadn.navy.mil>
ABSTRACT
APRStk.TXT        Differnces between APRStk and APRSdos
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
K10 Will not uplink AO27 at night and fixes D700 return to 144.39 1200 bd
    Separated SV35 from SO35 due differetn freqs for Voice and Digital
K09 Won't send DX spot if no sats due in 80 mins.
    Resolves Uplnk/Tune cnflct by using + for uplinks and T for track/tune
    Gets rid of the BLUE time line when Sat Sked is not on screen
K08 Transmits the next 80 minutes of SAT Skeds locally to DX-LIST in APRS
K07 Kills uplinked satellites after LOS
K06 Fixes too-frequent radio QSY with doppler.  Adds Xmit timing on P-List
    Now you can select a satellite for either "T" or "X" to track.  If
    "X" then it will also reset your transmit timing to frequent..
K05 adds ANALYZE command to plot # of pkts and EL angle during a pass.

APRStk is a copy of APRSdos with additional features for casually
monitoring the amateur satellites.  Major functions are: 

  * Displays sats on all screens
  * Will auto tune the D7 and D700 radios between sats and for Doppler
  * Can uplink these sats locally as objects for others to see
  * Can exchange Keplarian elements over the air

This file is a quick summary of  these added capabilities and assumes
you have a basic familiarity with all the power of APRS.  For more indepth
discussion of my overall  APRS/SATELLITE concept,  see ASTARS.TXT or
better go to my WEB page
       http://web.usna.navy.mil/~bruninga/astars.html
to see the latest.  Here is what APRStk can do for you:

OVERALL:  Just let APRStk run on a PC in the corner.  Connect to your
THD7 or TMD700 kenwood, set squelch  and adequate volume and you wont
miss anything on the birds that can be received with an FM radio.  The
best antenna is just a 20.25 inch vertical whip antenna over a 3 foot
or more ground plane.  It is 1/4 wave on 2m and 3/4 on UHF with good
gain overhead.  Short coax (typical of a mobile) is a must, or you
will need a preamp.  (Don't transmit through your Preamp!)

DISPLAYS:
* Predicts satellite pases over the next 2 hours and displays the times
  and peak elevations graphically. (Use NEXT command to choose other
  displays or FILE-FAST to see where they are going)

* Displays the names, Freqs and Modes of all amateur satellites.
  Hit the LIST-FREQS command.  Also LISTS-USERS on the PACSATS and
  LISTS-TELEMETRY too.  Bulletins show which satellites have DIGI ON.

* Displays the basic Keplarian Elements for easy comparison with new
  or old elements.  Hit the LIST-KEPS command.

* Displays locations of satellites on the map as objects. 

* Displays the NAVSPASUR 80 Mw Radar fence on the USA map.  When
  satellites cross that fence, you should detect a ping on 216.98 MHz
  +/- doppler.  The beam is only 0.2 deg wide, so it is Brief!

OPERATIONS:

* Shows the azimuth and elevation to any satellite selected.  Select
  either on the MAP or P-LIST.  To auto-track a satellite, then
  mark it for TRACK or XMIT on the P-List.

* Shows a set of elevation rings showing the range to satellites
  above 0, 5, 20 and 40 degrees from your location.  Note that this
  is dependent on satellite altitude and defaults to 800 km.  To
  change this use INPUT-EL-RINGS.

* Wont let you miss a pass.  If you are zoomed in below a range to see
  current satellites in view, it will paint the map the color of the
  current maximum elevation of any pass in progress.

* If connected to a Kenwood THD7 or TMD700 radio, it will auto tune
  the radio to the satellite frequency when any satellite (selected 
  for TRACK or XMIT on the P-LIST) gets above the minimum angle set
  in the SYSTEM\SATFREQS.SYS file

* Will QSY between satellite passes to 144.39 local APRS frequency if
  the "pseudo APRS" satellite is selected.  THis is a fake Geostationary
  satellite planted over the USA to serve as a default for 144.39. 

* Can uplink these satellite objects to your local APRS LAN to inform
  others.  To do this select them with UPLINK command on the P-List.
  APRStk will transmit them once per minute when in view, and then kills
  them once below -2 deg.  Every 10 minutes when the SCHEDULE is drawn
  automaticaly due to no-operator present, then APRStk will also send
  out a DX SPOT containing all passes in the next 80 minutes.  If there
  is an operator present, you can do this at any time with the NEXT-SKED
  command.


CONFLICTS!   APRStk can do two things with satellites: 
  1) UPLINK them as  OBJECTS on 144.39 or
  2) QSY the kenwood THD7/D700 radios to Hear them.

Obviously, these cannot work at the same time.  SO do not mark the same
satellites on the P-LIST for both TRACK and UPLINK at the same time.
This way it will not try to tune the radio to the satellite frequency
when it should be staying on 144.39 to transmit them as objects...

MULTIPLE-MODES:  If a satellite has multiple modes and frequencies it
has to be entered as multiple satelites with multiple elements in the
LEO.ORB file.  FOr SO35, for example, there are digital modes and voice.
I created a fake satellite called SV35 for the voice mode.  Whenever
you INPUT-KEPS-UPDATE, only the first one will take.  You will have to
manually edit the LEO.ORB file to update the SV35 satellite.

PACSATS DATA:

* LIST-LOG lists all UI packets received from the PACSATS
* LIST-USERS will show all the PBlist packets showing who is logged in
* LIST-PACSATS-TELEMETRY will show the telemetry packets (as decoded to
  hex by APRStk.
* BULLETINS will show which satelites have DIGI enabled.

OTHER DIFFERENCES:

* NOTE!  All packets to "TLM" are converted to HEX and logged that way
  to avoid scrolling or messing up the screens in APRStk
* Defaults to 9600 baud serial port speed to match the THD7 radios
* Defaults to CONTROLS-FILTERS-OTHER so that all packets are captured
  not just APRS formatted packets
* Defaults to CONTROLS-FILTERS-LIMIT to a path length of only 12 so that
  the lists do not overflow with distant 144.39 traffic.
* Does not auto-sort after 4 hours of user inactivity
* Uses APRS Compressed mode for shortest packets. (Not properly received
  by WinAPRS yet)

Note, you may not want to have the radio QSY back to the 144.39 frequency
if you live in a busy area, or it will overwrite your satellite contacts.
This is OK, if you have LOG on to autosave everything to disk, or you can
set CFL to 10 so that it will ignore all stations more than one digipeater
away, yet still sit on 144.39 for incoming message traffic.

ANALYZE:
To help you analyze your station's downlink effeciency, APRStk has the
ANALYZE command that plots the number of packets heard every 5 seconds
against the elevation angle..  With the THD7, you will see large spikes
every 20 seconds which is the TNC re-setting after each 5 KHz QSY.

BULLETINS:  The Bulletins page now generates a pseudo Bulletin based on the
telemetry value of the DIGI bit.  If DIGI is enabled on a satellite, it will
show on the BULLETINS page.

de WB4APR

