A ball type downhole lubricator valve features a ball rotating on its axis to open or close with control line pressure to an actuating piston. The impact well has the shape of a frustum and includes an upper portion, an intermediate portion and a base portion. In particular, for each frequency band handled by the circuit, the dual band bi-directional amplifier has a duplexer set for separating the signals from one of the bands into the uplink and downlink direction. The generating unit generates intermediate data in accordance with the print data including the pieces of image data, on which the trapping process has been performed. The client receives the true URL content in either case by submitting a request for the target URL once.