An intra-corporeal surgical retractor for holding tissues and organs in place is provided, including a sealed container, made from a flexible material, having an interior containing a granular substance and a fluid. A control section of the printer determines whether the printing jobs received by the receiving section include special printing, and causes a display section to display a list of the printing jobs including the special printing. Because the bandwidth of the envelope signal is reduced, efficient operation of the switching modulator can be achieved within wideband, high-speed communication systems.