Order Tray | Contact Us | Home | SIG Lists

[aprssig] Fixing older KPC-3 Duping Digis! (rev 1)

Cap Pennell cap at cruzio.com
Wed Aug 31 22:14:46 UTC 2011


Bob wrote:
<snip>
> Tom has made an excellent point, that the multiplication of dupes makes
this
> 8.2 fix an exponential dupe problem in areas where many 8.2 KPC3's can
hear
> the mobile.  I wonder if other areas have noticed this?

Yes, but it's not a actual significant problem.  I am probably one of only a
very few hams whom has ever noticed this effect on VHF in California (where
many of our digipeaters also are atop tall mountains), yet our VHF network
survives somehow.  We do set UIDWait OFF in these TNCs.  Remember too, "the
far side of the hill" is a different direction (and possibly additional
coverage area) for each digi that transmits a user's packet.  And individual
digipeaters sometimes quit working, so _a little bit_ of redundancy in the
VHF network is not always a bad thing.

> Anyway, the result of this revelation is to cause me to go back and REVISE
> the above recomemendation to INCLUDE the  "use only WIDE2-2" (or WIDE3-3)
in
> this area, (meaning WIDE1-1 is not supported).
> 
> RECOMMENDATION TO NEW MEXICO?
<snip>

I suggest you're over-working this a bit.  These days it seems VHF network
capacity is more significantly decremented by users' too-frequent
transmission interval settings than by their digipath settings.  In my view,
your suggesting that the "North American default routine mobile digipath" of
WIDE1-1,WIDE2-1 will no longer be recommended in Arizona is a very large
practical disadvantage to your newest plan.  And WIDE1-1,WIDE2-1 even works
in Southern California today too.  <grin>  Of course, fixed non-moving VHF
stations can use a less broad digipath routinely, like only WIDE2-1 or only
WIDE1-1 or only a single high digipeater's callsign (or only WIDE2-2 or only
"SSn-N").
73, Cap KE6AFE






More information about the aprssig mailing list