Scale calibration/zeroing in data gathering system

A data gathering system adapted to be installed within a checkout counter for determining information about products presented for purchase at the counter including the weight of products placed upon a weighing portion of an upper surface of the system which is substantially aligned with an upper surface of said counter, said data gathering system comprising:

• support means for supporting said data gathering system within said checkout counter, said support means defining a portion of the upper surface of said data gathering system;
• scale means secured to said support means and coupled to said weighing portion of the upper surface of said system for determining weights of products placed thereon;
• and
• scale adjusting means for calibrating and zeroing said scale means, said scale adjusting means comprising a scale zeroing switch connected to said scale means and being incorporated into said support means to be accessible to an operator of said data gathering system through the upper surface thereof and a scale calibration switch connected to said scale means and accessible to scale service personnel but inaccessible to an operator of said data gathering system whereby said scale means can be periodically zeroed and calibrated as necessary to maintain the accuracy of said scale means without removal of the data gathering system from said counter.