A packet communication device autonomously selects an appropriate operation mode according to a connection environment to an external device before a service of the device is started. Two indentations that are symmetrical relative to the longitudinal axis of the racket may be provided in the heart region of the frame. The data communication node includes a network reporting element capable of monitoring management information of an intermediate network coupled into a data communication path to the wide area network. The synchrocyclotron can further include an injection electrode and an extraction electrode having voltages controlled by the programmable digital waveform generator. The color is compared to one or more pre-calculated color tiles.