Precision 101

Higher yields. Lower costs. Less labor. What are you waiting for?

Central Illinois Ag is the third largest Case IH dealer of Precision Farming products in North America. We believe in it. Let us show you how you can directly benefit from Precision Farming with an in-depth product demonstration.

Precision Farming is the future; you will wonder how you farmed without it.

Ralph King Quote


GPS SatallitesPrecision Farming uses GPS (Global Positioning System) to determine the precise latitude and longitude of any location on earth. The GPS system is based on a group of satellites known as a constellation. Through the use of the US owned NAVSTAR (Navigation Satellite Timing and Ranging) and more recently the Russian owned GLONASS (Global Navigation Satellite System), GPS receivers installed in your equipment are able to use satellite signals encrypted with a correctional signal to pin point, in real time, an exact location on earth. The use of GPS helps you become more efficient with your machinery by reducing the amount of skips and overlaps which aids in reducing crop input cost, fuel machinery cost and total operation time.

At the same time, GPS allows you to keep more accurate records of site-specific information in the field such as crop yield, moisture, variety and population.


Depending on your specific needs, there are multiple networks that provide different accuracies in the field. The basic network known as WAAS (Wide Area Augmentation System) is a free system that comes standard on any GPS system. The WAAS network provides six to eight inches of pass-to-pass accuracy. For more precision, an upgrade to OmniSTAR is available that delivers two to three inches of pass-to-pass accuracy. And for those looking for the most precision available, you have the option to use RTK or the new RTX network. Both of these systems provide sub-inch accuracy for tasks that require precise implement placement year to year.


The RTK (Real-Time Kinematic) Network signal corrections are transmitted in real-time from a reference receiver at a known location to one or more remote rover receivers. The use of an RTK capable GPS system can compensate for atmospheric delay, orbital errors and other variables in GPS geometry, increasing positioning accuracy up to within a centimeter. Used by engineers, topographers, surveyors and other professionals, RTK is a technique employed in applications where precision is paramount. RTK is used, not only as a precision positioning instrument, but also as a core for navigation systems or automatic machine guidance, in applications such as civil engineering and dredging. It provides advantages over other traditional positioning and tracking methods, increasing productivity and accuracy. Using the code phase of GPS signals, as well as the carrier phase, which delivers the most accurate GPS information, RTK provides differential corrections to produce the most precise GPS positioning.

Central Illinois Ag currently has over 500,000 acres covered by our own RTK towers and we are adding more on a regular basis. We also work with surrounding dealers that have adjoining networks to provide seamless transition when moving from one area to another. Please contact any of our salesman or precision farming specialists to find out if you are covered, or if we are coming to your area soon.



Central Illinois Ag is dedicated to providing today’s producers with the most up-to-date precision agricultural equipment. We continue to offer many products from both Case IH and Trimble to meet all producers’ needs no matter how big or small. For a demo or more information, please contact your local dealer.

Visit our Precision Farming equipment page for information on the equipment needed to begin farming with precision.