[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:

Bob, Wb4APR

> -----Original Message-----
> Did some more thinking for the Appalachian Trail Golden 
> Packet.  Here are some possible refinements for the operations
> 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
> 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
> 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

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