On Fri, 23 Dec 2011 08:14:49 -0500, JustWait
wrote:


One can get accuracy to 3 ft, and even to 6 inches. Just have to throw
money at it.

Just with GPS? I was told the closest they could "tune" the atomic
clocks in the sattelites created a sloppy area. "That's why they can't
land a jet on an Aircraft Carrier with GPS alone, it can't account for
the pitch of the deck"...

The pitch of the deck has to do with altitude above sea level. GPS is
notoriouly very inaccurate on that.

Dang it, I forget the term, DPGS? Anyway you can set up your own
stations around the field to increase accuracy. I know you could buy
those units, but this was a while back. I hate to assume, but I assume
they're still available.




Years ago, before GPS, my company did a custom radio control for a
local cane farmer's tractor, with all the necessary failsafes. He
would drive the harvester and the R/C tractor with a fifth wheel
trailer alongside. When the trailer was full, he'd drive the tractor
to the pickup site, disconnect and hook on an empty and continue.

Was this GPS alone, something else, or a combination??

Uh, look at the first sentence, "Years ago, before GPS,...". It was
strictly radio control. We set up a custom panel in the harvester with
a couple joysticks and a few switches.

Rick