The company that I have been working with has gone commercial with the product this spring. They have a news release about "Intime Connection" on the front page. Yes it works if you have good cell phone coverage. I have no experience with repeaters, so I don't know how much lag time they add. But we have been running the cell system this spring planting corn. My correction age is staying pegged on 1 second. I have seen it range from .8 to 1.2 seconds. That is every bit as good as we got when we tried radios. I am using Sprint for my carrier, but have used Verizon also.

When we first started testing this system we used a dedicated cell phone modem. It worked, but was not an ideal solution. You had to have a computer (pda or laptop) connected to the modem for fire things off. Intime is now using the PDA type phones that are running Windows Mobile 6. They have written an application for the phone that automates the entire process. You just turn the phone on and things go from there. It is an internet based system. You have internet access in the tractor. We can pull up the weather radar at the push of a button. We can check the market prices at the same time the RTK data is streaming. We can send and receive email. They are using bluetooth to transfer the correction data to the GPS receiver. There is no cable connection between the phone and GPS. I have a choice of base stations I can use. If one goes down I can change to another. These are fixed site stations that are part of the CORS network. The signal is free.

In past years I have been using a station that was 29 miles away. I was not getting true RTK accuracy, but very close to it. This spring a group of local farmers got together and built our own CORS station. We did this in cooperation with the Alabama DOT. We bought the equipment. The DOT installed it and is operating it. We are getting the signal (by cell phone) from their network. The station is located on the roof of a local high school. The school had a good broadband internet connection. The signal goes out on the schools connection to Montgomery, AL (about 200 miles away) to the DOT network and then comes back to us by internet (cell phone). It is doing this in 1 second.

I have only had the cell signal drop on me 2 times this spring. Both times I was able to reconnect immediately. Our problem now is losing GPS around tree and we have trees everywhere. We are using external antennas with the cell phones.