Leonids Meteor Shower APRS protocol
To clarify exactly what a high power TX station needs to send is say 30 copies of the APRS grid format in a single burst IE send this to the TNC every minute:
GG##gg<CR> GG##gg<CR> GG##gg<CR> GG##gg<CR>
...
GG##gg<CR> GG##gg<CR>
The TNC will concatenate probably seven to ten of these at a timel into dense packets with only a single TX delay, not 30 delays.
The TNC has UNPROTO set to simply "APRS" no path! And set to CONVErSE..
Adjust the number (30?) till the TX burst lasts 15 seconds each minute. The result is a complete grid in only 200 milliseconds each. Hopefully short enough so that occasionally one will get bounced somewhere by the extremely short meteor path bursts at VHF.
Point beam to a high ham population density at least 600 miles away. Vertical or Horizontal will work.
This will take special software for the 15 TX stations. (METEOR-1 through METEOR-15)
RX stations need nothing special. Any APRS software should capture and decode and plot a grid report if received overnight. All of this on the national channel 144.39 from midniight to 6 AM local time
Here is the report form 1998 event http://aprs.org/APRS-docs/LEONIDS.TXT
Bob WB4APR
On Thu, Nov 12, 2020 at 5:06 PM GEO Badger w3ab@yahoo.com wrote:
Actually, I can program my spare TNC, KPC 3+, to TX every X seconds for X time.
Ciao baby, catch you on the flip side 73 de W3AB/GEO
WA2LSI, KE6RJW, AAR9AG
You can say "over", you can say "out", you just can't say "over and out".
On Thursday, November 12, 2020, 01:39:04 PM PST, Robert Bruninga < bruninga@usna.edu> wrote:
AMEN! Your location? Beam should point to high APRS population density about 600 miles away.
Do you have APRS familiarity? Though it is not required, bu will neet a PC program to send the 40 packets in 15 secs every minute,' Hopefully someone will write it quickly.
bOB
On Thu, Nov 12, 2020 at 3:39 PM GEO Badger w3ab@yahoo.com wrote:
I have 100W & 7 el beam. Will that meet the requirements?
Ciao baby, catch you on the flip side 73 de W3AB/GEO
WA2LSI, KE6RJW, AAR9AG
You can say "over", you can say "out", you just can't say "over and out".
On Thursday, November 12, 2020, 12:28:49 PM PST, Robert Bruninga via AMSAT-BB amsat-bb@amsat.org wrote:
We are seeking Amsat operators with beams and high power on VHF to participate in this coming Monday night's Leonids Meteor Shower APRS test.
So far, no one on the APRS list seems to have any power and beams to be a transmitting station. If you have high power and a beam, you can help. Here is the pitch:
With the Leonids Meteor shower coming up after Midnight next Monday (Tues AM), maybe its time to have some fun with APRS again!
Last time we did this was 1998 and over 48 MS packets were seen over 500 to 600 miles on the APRS channel.. Here is the report: http://aprs.org/APRS-docs/LEONIDS.TXT
THis year I propose not a free-for-all but just a few HIGH power stations transmitting and everyone else in the country checks the next morning to see what they copied.. Best TX stations are those with several hundred watts and a beam. Even one such station would be a great test, because on 144.39 we would have maybe 10,000 full time normal APRS stations as receivers. In retirement, i dont have the power nor the beam
But it would go something like this. Up to 15 TX stations around the country would TX a continuous keydown string of short packets for 15 seconds every minute. Xmission is on the 144.39 national APRS channel to maximize the number of people that might copy one. Transmissions begin at midnight local time and runs to 6 AM only to minimize any interference to other operators. We all wake up the next morning to see what we got. Yes, this will burn the local channel within about 20 miles of the TX station. but since the packets have no path, they can only be heard in simplex range of a transmitter and everyone is sleeping anyway.
But if a meteor happens, someone within about 400 to 600 miles is likely capture it. Remember, the APRS channel load in most areas is only a packet every 3 or 4 seconds and that gives everyone a receive window of 75% of the total slots available. And even if the TX stations are not even synchronized it doesnt matter because a given meteor path only exists for a fraction of a second and only between two fixed 100 mile or so areas for that instant.
The original APRSdos had Meteor Mode built in and did the timing and transmissions. WIth a very short packet and short TXD a single key down could transmit about 30 packets during each 15 second period.
Any high power TX volunteeers?
Oh, here is the original page: http://aprs.org/meteors.html Look about 75% down the page for the map of that 2m experiment.
IGNORE the majority of that page. It was showing how an emergency response station for example could go to an area of total devastation with all APRS wiped out, and with enough power and persistence could likely get out an emergency email message. This one time, test is completely different.
Bob, WB4APR _______________________________________________ Sent via AMSAT-BB@amsat.org. AMSAT-NA makes this open forum available to all interested persons worldwide without requiring membership. Opinions expressed are solely those of the author, and do not reflect the official views of AMSAT-NA. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: https://www.amsat.org/mailman/listinfo/amsat-bb
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Robert Bruninga