A system, method and system are disclosed for using a variable frequency clock generator to synchronize an average data rate over intervals of time in a variable clock domain to make it equal to a fixed data rate in a fixed clock domain while reducing electromagnetic interference, among other things. The inside of the first receiving chamber is heated by the gas cooler and the inside of the second receiving chamber is cooled by the evaporator. The intermediate frequency signal from the mixer circuit 2 is supplied to an AD converter circuit 4. The regulator is suitable for keeping the voltage on the output terminals of the transistors the same during the charging phase of the battery. Furthermore, by forming the portions facing each other left and right of the protruding portions asymmetrically, the effects to suppress the occurrence of moire stripes can be improved even more.