A base angle attachment assembly includes a connector for coupling to a base and a pole supported by the base. The other end of an inductor whose one end is to be connected to the first terminal is connected to the second terminal. Advantageously, scans using the aforementioned mask effectively remove a boundary on the silicon formed by the difference in the amount of laser beam irradiation received by the silicon, thereby improving electronic characteristics of the silicon. The method further comprises regularly scanning the frequency range to identify interfering frequencies generated by interfering networks operating within said shared medium, and assigning a frequency channel fk to each position SPi within the sequences FS based on the identified interfering frequencies, whereby the use of interfering frequencies is limited.