A routing node for translating and re-directing Signaling System 7 messages associated with ported subscribers in a communications network is disclosed. The implantable medical device may incorporate a battery, capacitor, circuit assembly, feedthrough assembly, and interconnect assembly with respective electrical terminals. Light beams are emitted from the light source so that they are nearly vertical to the surface of the bottom part, and the polygon mirror has a rotation axis at a position which is nearly parallel to the surface of the bottom part. Some of the methods utilize a second-order mathematical model of the dynamics of the actuators. One of the first and second clock signals is selectively synchronized to a reference clock signal.