[aprssig] How to originate local Frequency Objects correctly

Robert Bruninga bruninga at usna.edu
Sat Jan 27 16:09:47 EST 2018


> I have recently started project called, "Minnesota Object
> Repository Beacon Station" (MNORBS).  I do an object beacon
> for each of the objects in my repository (such as a repeater).

Just remember that OBJECT beacons *originated* at high-site digipeaters are
WELCOME to provide useful local frequency info to travelers entering the
area, BUT they are generally not welcome when they originate at home
stations and JAM other users.

There is a huge difference.  When essential Frequency Objects are originated
at the digipeatere, they do NOT compete with other users.  Because they are
not on the uplink, and the Digipeater simply inserts them in to a slot when
no one else is using the frequency.  They are only transmitted once, and
they do not collide with anyone else.

On the other hand, originating these objects down on the ground is just
another source of interference that collides with all the other traffic on
the channel, not only cutting throughput in HALF because the object uses two
slots instead of one, but also blocking other people's packets.

The original Kantronics TNC's as digipeaters can originate typically three
additional local area objects FROM THE DIGI itself using the BTEXT and
LTEXTS as well as the digipeatr's own information (usually using 2 LTexts so
that the DIGI appears locally direct once every 15 minutes and via other
digis once an hour..

Please see http://aprs.org/localinfo.html

If someone in your area is flooding the local channel by sending useless
objects to the digi, please make sure he understands the burden this places
on the channel.

Bob, WB4APR



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