An information attaching unit attaches either one of carrier density information of initial developer and loose apparent density information of toner in the initial developer to a housing of a developing device. The power line communicating and AC power monitoring device is connected to a power line of a corresponding target device to retrieve and transform statuses of an AC power in the power line into network packets and sends the network packets out through the power line. Optionally, the conductivity of the pattern area may be improved by heating. This receptor has been determined to be present in growing cancers such as pancreatic and colon cancer, for example. The voltage control oscillator generates a bias current according to the first control voltage and increases or decreases an oscillation frequency according to the boosted or lowered first control voltage, and symmetric loads of the voltage control oscillator are controlled by the first control voltage.