[aprssig] The best resolution of position from APRS

J. Lance Cotton joe at lightningflash.net
Tue Jan 3 14:42:50 EST 2006

Curt, WE7U wrote:
> The Kenwood ratios _do_ decode Base-91 compressed posits.  What they
> _don't_ decode is base-91 compressed object/item format.  Why
> obsolete the entire format just because the Kenwoods didn't
> implement that part of it?  The vast majority of the APRS client
> users out there have the capability of using this protocol, even for
> objects and items (see the chart).

Base-91 Compressed position reports are Good. They bring a huge benefit to 
144.39 MHz as a much better use of the RF we are given.

I would advocate for continued and expanded use of compressed format AS LONG 
AS those who use it understand the limitation, which is small: "don't send 
object/item reports using compressed mode"

We can continue to be good stewards of the radio space given to us by using 
it as efficiently as possible.

And it is possible to do this and not leave anyone out, as long as we are 
aware of how to use it. This is the case in everything.

An even more efficient use of the channel is the OpenTRAC protocol. It can 
be used without harming ANY APRS users, but users of OpenTRAC should know 
that no APRS users can see them, which makes it of limited use at this time 
on this frequency.


J. Lance Cotton, KJ5O
joe at lightningflash.net
Three Step Plan: 1. Take over the world. 2. Get a lot of cookies. 3. Eat the 

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