[aprssig] WIDEn-N 'Decay Sequence'

[Mark Earle]

At 10:48 AM 6/19/2006 -0400, you wrote:
 >At 10:05 AM 6/19/2006, Mark Earle wrote:
 >>As Bob will tell you, APRS is a local tactical system. Emphasis on LOCAL.
 >
 >Yes. My interest lies in exactly that area. When I first
 >hooked up my D700 and it told me it was getting packets
 >from 178 miles away, I was like, "Huh?"

Many digi operators are trying to change that :-). If mobiles use:
WIDE1-1,WIDE2-1   (trackers, D700, whatever) then you will see (usually) 
only local packets.

Many digis now "trap" what are deemed (by the LOCAL digi owners) excessive 
paths -- if a stubborn user puts in WIDE7-7, it doesn't go anywhere, or, 
perhaps gets ONE hop. We hope the user will notice this and change to a 
more reasonable setting.


 >Got it. Now, what is the purpose of the 'little n'?
 >(that is, the 2 that doesn't change in the above
 >example)

Basically, it is the "how many hops do I (the user) desire". However, many 
digis now trap larger values.

 >that the set up for the digipeaters is a string like
 >"RELAY,WIDE,WIDE1-1" (note that I'm not saying that this
 >is a _recommended_ setup string *grin*) So does the
 >digipeater just parse the packet, and if it contains
 >one of those strings, rebroadcast it?

Yes. Most digis also dis-allow "excessive" paths, such as WIDE7-7. HOWEVER, 
they also support a "state" alias. Usually, those WILL allow wider than 
normal digipeating, on the theory that if you (the smart user) change your 
path to WA7-7 (say for Washington State), then you have some need for your 
packet to get out widely to all of the state. However, adjacent state digis 
ignore this, since they are set up for their own state.

 >>So, the idea is, no matter what - the mobile user sets up WIDE1-1, WIDE2-2
 >and does not have to reconfigure. Useful for other than D700 users,
 >trackers, etc.

Oops, I meant:   WIDE1-1,WIDE2-1

 >
 >And a D700 user should use what? And why would they be

WIDE1-1,WIDE2-1     Unless you are using the state alias. Or, if you NEED 
to go 3 hops, you may want: WIDE3-3    or    WIDE1-1,WIDE3-2   BUT, those 
should not be used normally - your packet may go a LOT further than 
necessary. Those would be "boonies" settings :-)

 >different than any other mobile user? (I have a D700 and
 >understand that *my* capabilities are significantly
 >different than other mobile APRS users, but don't
 >understand why I would want a different path setting
 >for packets I transmit.)

Nope - use the WIDE1-1,WIDE2-1. I suggest a setting of a new posit every 2 
minutes for most daily use. IF you leave your radio/ gps on while 
stationery, you may want to set it to 30 minutes. (You can store two "PM", 
one with 2 minutes, and one with 30).

This new paradigm stuff is great for trackers that require a PC to change 
paramaters. One setting fits all, for most uses.

 >
 >I tried http://www.google.com/search?q=fix14439.txt but got
 >no hits... typo?

Hmm. Try this link, it just worked for me:

http://eng.usna.navy.mil/~bruninga/APRS-docs/DIGIS.TXT



 >
 >Thanks for the info Mark. :)
 >
 >Cheers,
 >Anders



       ) )    de WA2MCT Mark
      ( (     Echolink 99190      Grid Square EL17HQ
       ) )    You will be assimilated... oooh, coffee!!
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