A coin dispenser includes coin storage tubes each with a dispensing mechanism located directly below each tubes. In one embodiment, a method is provided that identifies a printing defect on a hardcopy document, the printing defect being created by a printer, identifies a non-printed digital document affected by the printing defect, and, prevents a printing of the non-printed digital document affected by the printing defect. Ground coordinates for a ground control point, and image coordinates of the image matching the ground coordinates are acquired. Fasteners may be placed through apertures in inner portions of the stability members into the top surface of the support pedestals to further secure the stability members to the support pedestals. Group TDMA provides increased throughput capacity as it provides a balance between scheduled access and pure random access.