[aprssig] Appalachian Trial Golden Packet!
Robert Bruninga
bruninga at usna.edu
Mon Mar 16 17:45:26 EDT 2009
We now have a target date for the Appalachian Trail Golden
Packet Event:
To coincide with the AT annual conference this year on the
18th/19th weekend in July. Can anyone thinnk of any conflicts?
Also, some sites can use Field Day the month before to check out
paths. We also now have a web page:
http://www.aprs.org/at-golden-packet.html
Bob, Wb4APR
> -----Original Message-----
>
> Did some more thinking for the Appalachian Trail Golden
> Packet. Here are some possible refinements for the operations
plan:
>
> STATION ABREVIATIONS: We need very condensed station
> tactical nomenclature. Ideally we could use a single byte
> using A-Z and 0-9 for 36 hops. But this would be impossible
> to coordinate, since any change would affect ALL participants
> over the entire 2000 miles. So I propose two bytes. We
> break the trail into 6 regions where each region should be
> able to make the links with 5 or 6 peaks each. Then we can
> refer to the region by first letter and a digit to represent
> the peak in that region.
>
> M# for Maine
> E# for New England
> N# for Ny/Nj
> P# for PA
> V# for Virginia
> S# for the southern states
>
> STATION CALLS: We could use ATX-# where X is the byte above
> and # is the SSID. (Most APRS software expects at least 3
> letter callsigns).
>
> STATION TEXT: Each station begins with simply his FCC call
> as his only position text. But as he begins to see other
> stations, he can "qsl" them by inculding their X# in his
> text. Example: WB4APR,V1,P6 which means WB4APR can see
> other stations as far south as V1 and as far north as P6 and
> all stations in between.
>
> FREQUENCY: This will be hard, but we have got to find an
> underused packet frequency that is pretty clear along the
> entire east coast. But we can all easily monitor from our
> shacks in preparation to find any hot spots.
>
> UIFLOOD PATHS: We only need to trace the message paths, not
> the station postions paths. This will drastically reduce the
> length of each packet. So we set all portable digipeaters
> with UIFLOOD set to HOP and NOID. This will support HOP7-7
> paths for position reports. As we watch APRS we can see the
> trail stations appear + and - 7 hops in both directions from
> each site.
>
> UITRACE PATHS: The special messages (Golden Packets) will
> use the Traceable TEMP7-7 paths for accountability.
>
> MESSAGES: We will use ONLY BULLETINS (BLNx) say NORTHbound
> and only ANNOUNCEMENTS (BLN#) southbound. This eliminates
> ACKS and QRM.
>
> RE-TRANSMISSION: This is the key to concise operations, and
> I am not sure I have a final suggestion here. But once a
> packet has gone 5 or 6 hops or so through a region, the very
> long traceable path has to be stripped off and re-launched
> with a new TEMP7-7 path. My thinking is that this
> re-initiation would occur at each of the "region" boundaries.
> This makes it easy to abbreviate passage along the 5 or 6
> hops in that region by simply inserting the LETTER for that
region.
>
> So a north bound Golden Bulletin would begin at Springer
> Mountain as a BLNA, but once it gets through all the Southern
> region peaks to VA, the bulletin would be started over as a
> BLNAS (showing it passed through all the "S" southern peaks
> successfully). When it gets to PA, then it would be
> regenerated as BLNASV and so forth. On arrival at Mount
> Katadin in Maine it would arrive as BLNASVPNE and would also
> have the last 7 actual HOPS in its header.
>
> Since the originators call will be lost at a retransmission
> station, then the first 3 bytes of the re-transmitted
> bulletin will be the originators abbreviation (and a colon).
> Eample: "BLNASVP ... S1:What hath APRS wrought?" would be a
> message originated at station S1 that has made it through all
> the SOUTH, VA and PA peaks...
>
> So to pull this off, we only need to have 7 full function
> APRS packet stations at these key regional boundaries for
> easy re-entry and typing of the message and all the rest of
> the stations can simply be a D700 mobile (or portable KPC-3
> TNC digi) parked at the right place!
>
> Oh, we also of course need a UHF voice coordination channel.
>
> SWITCHING PATHS: To be able to switch between the HOP7-7 and
> TEMP7-7 paths for our positions and for our messages, I
suggest:
>
> 1) use the high power portable digi itself to send the
> MESSAGES via TEMP7-7. And disable its own position packets.
>
> 2) Use an HT or other APRS station to send the local station
> position via HOP7-7. It will get picked up by the co-located
> higher power digi and propogated efficiently (without the
> cumbersome traceable TEMP7-7 overhead).
>
> Bob, WB4APR
>
More information about the aprssig
mailing list