|Using findu.com's message sending facility at
I sent the following APRS messages from/to the unit's callsign (KJ4ERJ-7 in my case):
PARM sets the names of the various parameters
You may need different coefficients depending on if you're using the higher resolution settings. Mine are on low resolution and seem to track some semblance of reality (the TT4 is on a West-facing window sill in Palm Bay, Florida).
You can read more about setting up telemetry at
as well as in Chapter 13 of the APRS Spec from