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[aprssig] TNCX setups?

Kai Gunter Brandt kai.brandt at hjemme.no
Fri Jul 17 06:51:42 UTC 2009


Cap Pennell wrote:
> I'd extend the Beacon 3 and Beacon 4 intervals out even further, and/or
> reduce their paths.  No help (for it's VHF users) for a digi to transmit
> it's own position packet more broadly than across the next digi hop in all
> directions.  Only reduces available airtime for all the other _users_ of the
> VHF freq.

I should have a disclaimer ;o) For now the traffic in Norway is low.
When this is changing we can easily adapt.
But if you compare the beacon rate from 3-4 digipeaters every 30/60min
with beacons from 10 mobile/portable stations then i think the digis are
the one that have to struggle to get trough ;o)

> A full service WIDEn-N/SSn-N digi like this sample setup (first one below)
> will be in a very good wide area network location, in cooperation with all
> the neighbors, and so will surely be seen on the internet too with only a
> minimal VHF digipath.

Most of the digipeaters in my area is at a mountain reaching 100Km or more.

http://aprs.fi/heard/LD5SK
http://aprs.fi/heard/LD5GU
http://aprs.fi/heard/LD5BE
http://aprs.fi/heard/LD5VO

Select "terrain" in the Google options.

Within 3-4 hops there are IGATEs in most areas (and again i'm talking
about "my" area in Norway)

Beaconing a reapeater/echolink object on a direct path every 10min i
don't think is bad.

Beaconing its own position one jump every 30min i don't think i's bad-

Beaconing its own position two jumps every 60min i don't think is bad.
If you are driving from i.e south Norway and going north theres a lots
of "gaps". Then you know where you can expect to be digipeated the next
time. This also is a indicator if one/more digis are QRT.

But i agree to that using beacon with SSn every 60min with 3 jumps is
generating QRM.

> Most often these days, a simple traceable fill-in digi is far better for our
> shared VHF network.  A traceable fill-in digi operates packets addressed via
> WIDE1-1 or it's own callsign ONLY, as in the final (second one below) sample
> setup.
> (UICall 1: WIDE1-1 and have UIFlood and UITrace empty.)
> 

Due to the terrain in many parts of Norway we need many Fill-In digis.
We also have some QTH where we have to use a Fill-In where you usually
want a wide area digi if not the digi is digipeating every packets half
the country in one jump just to exagerate a bit.

So the disclaimer for the example ;o)
It's for a new WIDEn-N setup or for a Fill-In
beacon interval, beacon text/objects and paths has to be adapted to your
area. The format of the beacon text i really like as it's very
informative and more or less a standard.

In Norway we use 144.800MHz for aprs and i have seen digipeaters sending
out information like "SomeDigiCall 144.800MHz APRS digipeater" this is
NOT informative as i know that 144.800 is aprs ;o) and i know that a LD
callsign is a official callsign for a node/digipeater. I also know the
callsign for the digi so it's no use to put it in the beacon text.

In Norway local IGATES use either WIDE2-1 in their paths or the callsign
for the nearest wide area digi.

Regarding the dupe time we have a <10sec delay if you check aprs.fi and
the radio at the same time.

And this value is easily changed if needed as the TNC-X with XDigi can
be remotely controlled.

Anyhow i think it's easier for digipeater sysops to control the network
rather that the users are doing all sort of tricks as this is something
spreading like a virus and then everybody are using strange paths.

The only thing i would like to be more stable is the messaging functions.

And to be off-topic i really want lotz of aprs satellites so that we
don't have to think about making a keplar schedule.

Kai Gunter
LA3QMA



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