[aprssig] Balloon crossing near CLEVELAND now on GND in WV?

Robert Bruninga bruninga at usna.edu
Fri Jun 8 14:26:27 EDT 2018

Balloon Path:  Apparently the digi path was a mistake.  The tracker was
supposed to  switch to direct above altitude, but it did not.

But what many people might miss, is that every digipeater in a few hundred
miles is going to hear the packet direct and digipeat it anyway. And once
having done that, it will ignore any further path info.

So even if a balloon screws up with a multhop path, it is still only going
to be digipeated once and only once for every digi in range.  So, not that
much difference.

HAVING SAID THAT, of course, there is a secondary effect to a double hop
path at altitude.  And that is that if a digi missed it the first time, it
will have other chances to hear it additional times possibly from an
adjacent digi.  But again, the result is the same.  Every digi in range will
still only digipeat it once and only once.  And for users in range of that
digi, they will only hear it once via that digi.

1) They may hear the balloon direct if they are outside
2) They may hear one and only one copy from their local digi
3) If they are in range of multiple digis, they all digi at the same time
and again, only take up one slot time.  So again, the total slot time on the
National network is still just 2 slots.  The  original and one copy (plus a
few straglers in other areas)

For an exciting few hour event, this is no more load on any local area than
a local mobile driving through.

Again, the best path is two hops when on the ground or below 1000' and no
hops at altitude.  But the damage of a 2 hop path at altitude is not as bad
as some may think.

What IS BAD, is doing anything more often than once a minute.  Anything
faster than that is bad in my opinion. Since it is now worse than any other
APRS user, anywyere...


-----Original Message-----

Why would a balloon at nearly 40K ft have any path at all (wide1, wide2)? It
appears to be lighting up digipeaters for hundreds of miles in every

What exactly is the best recommended practice for high altitude APRS


More information about the aprssig mailing list