[aprssig] Speed transmit suppression

Curt, WE7U archer at eskimo.com
Fri Feb 3 17:28:29 EST 2006

On Fri, 3 Feb 2006, Floyd Rodgers wrote:

> Ok, simple question most likely asked before;
> Can ground speed be suppressed sending on transmitted dated? If yes, then how?
> (currently most interested in applying to tinyTrac3, but tnc will come later)

Check the TinyTrak3 config program:  It may have a checkbox for
enabling/disabling speed.

OpenTracker _does_ have such a checkbox.

Another way to disable sending speed is to only pass NMEA sentence
"GPGGA" to it from your GPS.  That sentence has altitude in it but
no speed.

"GPRMC" has course/speed, and is usually the one that gets parsed by
the APRS TNC's in order to derive speed.

As for a TNC, get one that is APRS-capable and then set it up to
only send GPGGA sentences over the air.  Any NMEA sentence is rather
long on the air, but this _would_ give you the sort of capability
you're after.

Curt, WE7U.   APRS Client Comparisons: http://www.eskimo.com/~archer
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