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Leonids Meteor Shower APRS TEST



The Leonids Meteor Shower in two weeks (17-18 Nov) will be an excellent
opportunity to experiment with MS on 2 meters using very brief Grid Square
packets.  During the Persieds in 1995, APRS stations recorded over 18 DX
packets on 2m of paths between 600 to 1200 miles.  This year we can do
much better for two reasons.  
 
   1)  There are far more APRS stations on the air
   2)  Since all of APRS has QSY'ed to 144.39 in most areas of the
       country, this leaves 145.79 available for a QRM free
       Meteor shower 2m packet frequency!

PACKET FORMATS:  The best packet is one of the APRS formats so that other
statons will instantly plot you on their maps.  All packets should be
transmitted as UI packets.  Here are several APRS formats using my station
and my gridsquare of FM19DX as an example.

 WB4APR>FM19DX:]-[Bob      This is the Grid-In-TO format XMTed by APRSdos
                           in MS mode.  It will be plotted by all other
                           APRS stations and all versions of APRS software

            TNC-ONLY:      This grid-in-to format can be sent by any non-
                           Kantronics TNC by setting the UNPROTO to your
                           gridsquare and setting BText to ]-[xxxx...
                           Then set B E 1... for 10 second XMT rate.

 WB4APR>BEACON:[FM19DX]Bob This format can be placed in Kantronics TNC
                           BText and sent every 1 minute with B E 1.
                           It is longer, and infrequent , but it will be
                           decoded by all stations.  

 WB4APR>FM19DX:            This is the same as Grid-in-to and can be sent
                           by any TNC by setting UNPROTO to your GRIDSQ
                           and then going to CONVERSE and hitting ENTER
                           key as often as you like!  See timing below:
                           It is the shortest possible position packet!

            NOTE:          THis format will NOT AUTOMATICALLY BE RECEIVED
                           by other APRS stations unless they are in the
                           Meteor scatter or GRID-IN-TO mode or have their
                           FILTERS set to receive all packets.

APRSdos alt-S-FORMATS-MSCATTER MODE:  This mode configures your station
to receive GRID-IN-TO packets and to TRANSMIT them for 15 seconds
continuous according to the regional timing plan.  If you have less than
50 watts and dont want to QRM other locals, do not set APRSdos to
MS format but set alt-S-FORMAT to grid-in-to.  This way you can reveive
MS packets.  Both of these automatically set your FILTER to OTHER...

PATHS:  Do not set your UNPROTO to anything.  We dont want to see any
digipeaters here!
                                                        
TIMING:  To organize transmitting an reception periods for this test, the
USA is divided into 4 regions.  Each will transmit for 15 seconds and then
listen for the remaining 45 seconds  Starting with the Northeast at 00
seconds followed by the SEast at 15 seconds and then the SWest at 30
seconds and then the NWest at 45 seconds of each minute.  All of this
timing is built into APRSdos if you are running alt-S-FORMATS-MScatter
mode.

ICONS:  The ]-[ is the HOUSE Icon.  Use ]Y[ if you are using a Yagii, or
]`[ if using a dish, or any of the other hundred APRS icons...

BEAMING:  Point your beam at one of the other 3 quadrants and go for it!

STATION REQUIREMENTS:  Although some MS packets have been seen on OMNI
antennas, these are very rare.  Usually about 10 dB gain from a beam is
required to receive these weak packets.  Transmitting stations should run
as much power as possible.  ANything less than 100 watts will have to be
very lucky.

FREQUENCY:  All stations participating should operate on 145.79 except in
SOuthern California where 145.79 is still the main APRS channel.  So here
are the recommendations:

   ALL USA (not SoCal):  Operate MS on 145.79 for the duration of the
                         event.  You may even hear SoCal regulars...
                       
   Southern California:  1) Try to listen on 145.79 for weak MS packets
                            amidst the local QRM. Dont transmit 15 sec
                            key-down on 145.79 or you will make enemies...
                         2) Transmit high power on 144.39 and hope that
                            someone in the rest of the USA will hear you.
                            (But only accidentally, since the serious
                            MS stations will all be over on 145.79).
                            BUT you will make BIG enemies locally of the
                            ATV people that use 144.39
                         3) Listen on 144.39 for weak DX packets from all
                            the rest of the USA on APRS that are NOT
                            participating in MS on 145.79
                    
If you run APRS, see the METEORS.TXT file included in all the README
files for more details.  TEST beforehand.  The APRSdos MScatter mode has
not been used much in the last 3 years, so I hope it still works!


de WB4APR, Bob



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