[AT] OT-now GPS

[Greg Hass]

I bought a GPS unit three years ago. Bought one of the cheaper units at 
a little over over $700. If I were doing it again, I would probably try 
to afford a $ 1500 unit.  The one I have works good for spreading 
fertilizer and I have sprayed with it once or twice but it is somewhat 
limited. For instance; a relative bought the more expensive unit and he 
can hook it to a sprayer controller and it will  tell the unit ground 
speed and is more accurate on the swath width.  As was mentioned, I to 
have noticed accuracy is greatly affected on rough ground. The book says 
to mount the antenna on the roof of the cap to get a clear view of the 
sky; however, that far off the ground on rough ground I know the antenna 
is moving 2 feet back and forth and the reading in the tractor is 
unstable so I just pick an average and drive accordingly. When spreading 
fertilizer I go 40 ft. swathes and it overlaps some anyway so a foot or 
two is good. Without the GPS my swathes would vary 10 or 20 feet 
depending on which tracks I followed. The way I understand it, 
auto-steer is a whole other beast. My cousin uses one and the way I 
understand it, it does not operate like the GPS we are used to. His uses 
antennas placed on cell phone towers over a three county area. A couple 
of dealers in that area got together to make the system. They say the 
satellites are not accurate for things like planting corn as their 
system will keep the planter within a one inch spacing. This system is 
not cheap as my cousin says the fee for tower use is about $3000 per 
year plus the equipment to mount on the tractors is about $15,000. We  
do have many people in our area using this system. My cousin says that 
he figures this system saves him well over $10,000 a year in labor, 
fuel, and extra wear caused by overlapping too much or having skips 
which the field cultivator missed. The downside is all these people are  
working at least 1500 acres compared to my 100 so I have to stick with 
the old ways just due to the cost.
            Greg Hass