Chris KF7FIR wrote...

> The workaround turns out to be easy. All I have to do is put in a small
> non-zero value for the Slow Beacon Threshold Speed. Apparently the
> T2 doesn't like 0 MPH even when the Slow Beacon Rate is set adequately
> large (e.g. 7200 sec).

It may just be your GPS receiver wandering around a bit. I don't think that
I would go with a 7200 second beacon rate for the slow speed. That's two
hours, and many APRS clients have a default expire time of 60 minutes. While
7200 seconds would reduce the load on the APRS network around you when 
you weren't moving, it would also mean that anyone arriving at your area
could have a very long wait to see where you were.

How about 1800 seconds for the slow rate and 5 mph for the slow speed, and
then 180 seconds for the fast rate and a fast speed of 10 mph. This is assuming
that it is always used on foot. If it is going to see duty in a vehicle as well 
as
on foot, I would instead recommend 600 seconds / 60 seconds (if you drive
mostly in town) and 5 mph / 50 mph for the slow and fast speeds. Corner pegging
would be responsible for most of your beacons while on foot. For someone that
did mostly highway driving, I would probably back the fast rate off from 60
seconds to 180 seconds.

If you mostly use it on foot, you could go with my first suggestion of just
setting the slow and fast speeds the same, and entering a responsible beacon
rate for both of them. I don't think too many people would complain about a
3 minute beacon rate from a low powered handheld device. Corner pegging
would again force it to beacon when you turned a corner.

Have you tried something like VisualGPS to look at the output of your GPS
receiver? If you are walking in a city surrounded by high rise buildings, you
could be dealing with lots of multi-path that could make the GPS think that
it was wandering around a lot more than if it had an unobstructed view of
the sky. I have a friend that reports that he deviates as much as a block or
two in the same part of town on a pretty regular basis. I think in his case,
it's could be more than an unobstructed view of the sky and multipath. I don't
have anything to back it up, but there could be a GPS jammer or something
else creating QRM  very close to the frequency used by the GPS satellites.

It's downtown Vancouver BC that he observes this, mostly along Georgia St.

73 es cul - Keith VE7GDH
--
"I may be lost, but I know exactly where I am!"

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