[aprssig] New User Question(s)

[Curt, WE7U]

On Mon, 5 Jun 2006, Mark Miller wrote:

> I have a basic question about the WIDEn-N parameters.
>
> I think I understand that the first number indicates the desired number of
> hops, and the second number indicates the number of hops remaining.  I
> understand the concept of WIDE1-1, but cannot understand WIDE2-1.  If 2
> hops are desired, then why set the second parameter to allow only 1 hop?

A very good question.  You are correct that WIDE1-1 and WIDE2-1 (and
WIDE7-1 for that matter) specify one hop.

The difference is this:  We use WIDE1-1 for the fill-in digi's,
which are at a lot of low-level locations like people's homes.  If
you use WIDE1-1 as the _first_ item in your path, then you get the
advantage of triggering the home fill-in digi's OR the mountaintop
WIDEn-N digi's.

Now, if you do a path like this:

    WIDE2-2,WIDE1-1

You end up triggering the mountaintop digi's for two hops, then
mountaintop digi's _AND_ the fill-in digi's on that third hop.  Not
good.  It causes quite a racket.

Stick to WIDE1-1 as the _first_ element in the path, then if you
need just one more hop, add WIDE2-1 as the 2nd element.  WIDE2-1
doesn't trigger the fill-in digi's, but gives you only one hop on
the mountaintops.  If you want three hops, then you go with
WIDE1-1,WIDE2-2.

The paths above are mostly for mobile stations.  Home stations
should generally use WIDE1-1 or WIDE2-2, unless they also need help
from a fill-in station to get to the mountaintops.

Hopefully that makes sense.  We had to abscond with WIDE1-1 for the
fill-ins in order to make the new paradism digi scheme work right,
then use WIDE2-1 for the mountaintops in its place.

--
Curt, WE7U.   APRS Client Comparisons: http://www.eskimo.com/~archer
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