Disclosed herein are systems, devices, and methods for orthopedic surgical guides adapted to the anatomy of a patient and configured to align a bone shaping device or acetabular implant in a predetermined orientation. According to the method and apparatus, a differential signal can be transmitted over two wires or two single-ended signals can be transmitted over the two wires. The PLC signal address relation information indicates the relations of the logic switches on the ladder diagram. The whole surface of the frame shades the film, except for an opening for the film pack.