[aprssig] My home station path WIDE2-2

Keith VE7GDH ve7gdh at rac.ca
Wed Aug 29 12:32:04 EDT 2007


Joe NE3R wrote...

> I often need two hops for my packets to be seen just 25 miles to the
> west and north of my home station in Frederick Maryland, but this same
> path causes my packets to travel a good 75 miles or more to the east.
> There is a wide digi on the mountain just to the west of town, and
> everything to the east is fairly flat.  Is WIDE2-2 appropriate in this
> case? I've been thinking about changing it to WIDE1-1, but that would
> mean not being heard by stations that really aren't
> that far away.

If you are within site of a WIDEn-N digi, a two hop path of WIDE2-2 should
get you via the digi west of town and out to (barring collisions) all other
WIDEn-N digis that can hear it. If your goal is to specifically get to 25
miles west and north of your location, you could use specific digis in your
path instead of a generic path. That could prevent your beacons from going
the 75 miles to the east. The disadvantage is that path would ONLY work when
you were within range of that digi that's west of town.

> What is the best way to determine the most appropriate path?

There's nothing wrong with asking on this list. Looking at paths of others
around you can be helpful, but that doesn't mean that they are using the
most ideal path. If you were a mobile station, I would suggest a generic
path of WIDE1-1,WIDE2-1. The advantage of this is that the WIDE1-1 will be
acted on by that digi west of town if it hears you AND by any WIDE1-1
fill-in digi that hears you. If the fill-in digi hears you and the mountain
top digi doesn't - perhaps the result of packet collisions - the fill-in
digi will retransmit your beacon and hopefully be heard by that WIDEn-N digi
west of town and any other WIDEn-N digis that can hear it. If you really
need to get to 25 miles north of town and two hops isn't enough, you could
(again if you were a mobile station) use WIDE1-1,WIDE2-2 but that will give
you a three hop path and will probably reach the areas to your east that you
are describing and it sounds like you are trying to avoid QRM in that
direction.

However, looking at map.findu.com/NE3R it appears that you are a fixed
station. That being the case, you could use a specific path rather than a
generic one to get your beacons to locations 25 miles to the north if that
is your goal (and within your ALOHA circle)... e.g. you could use a path of
N3KTX-2 followed by by a specific digi that was off to the north and west...
again assuming that was your primary goal.

Being a home / fixed station, you should definitely NOT start your path with
WIDE1-1.

Can N3KTX-2 be heard 25 miles to your northwest? If it can, a ONE hop path
of JUST N3KTX-2 should accomplish your goal. However, you say you need two
hops to reach 25 miles to your west and north. It just depends on what you
are trying to do and what the local network will support... i.e. paths that
will "work" and paths that are acceptable.

If you are trying to reach a specific area, using a specific path rather
than a generic path is probably the way to go especially if you are a fixed
station. Mobile stations should stick to generic paths.

Looking at www.db0anf.de/app/aprs/stations/digiusage-NE3R you have been 
heard by another digi, but the majority of your beacons are going via 
N3KTX-2. Again, I would suggest starting your path with N3KTX-2 and then 
look for a digi that is in the area that you are trying to reach if you do 
need one more hoop and add that to the path after N3KTX-2.

73 es cul - Keith VE7GDH
--
"I may be lost, but I know exactly where I am!"





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