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[aprssig] pointless text in the status

Curt Mills archer at eskimo.com
Thu Jun 1 02:32:39 UTC 2006

On Wed, 31 May 2006, Stan - N0YXV wrote:

> That brings up a question I've always had. How much more does each character
> add to the overall loading of APRS. In other words if I use 10 characters in
> my status text instead of 20 have I cut my packet in half? Put another
> way...if 10 characters plus all header and tail bits in a packet is half a
> second long will 20 characters be one second long? My question revolves only
> around network and network loading.

Hmmm.  I've wondered the same thing, so many years back I ran some
experiments to see what effect packet-length had on my packets
getting through.  I didn't collect statistics at the time, but just
got a good look-and-feel for it.  I started with GPGGA or GPRMC
packets, then went to APRS-formatted packets, then to Mic-E, then to
Base91 Compressed.  I had a bit of trouble with getting corrupted
Mic-E packets back then because some of the igates or TNC's were
messing up Mic-E protocol at the time.

Anyway, to make a long story short, as the packet length decreased,
the number of packets that actually got received somewhere increased
dramatically.  So much that now I usually run with no comment and
with no added parameters which might make the packet longer.

All of the other conditions were about the same, I was running a 25W
IC-27A and a mag-mount antenna on my Chevy truck, and driving about
the same commute every day.  I ran a few days to a week with each

I now run with an OpenTracker-1 set to Base-91 compression.  I don't
have any comment set while moving, but when I'm parked it transmits
the Jeep's battery voltage in the comment field until the APO kicks
in and turns the equipment off.

Curt, WE7U.				archer at eskimo dot com
  Lotto:  A tax on people who are bad at math. - unknown
Windows:  Microsoft's tax on computer illiterates. - WE7U.
The world DOES revolve around me:  I picked the coordinate system!"

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