SELECTIVE CALL RADIO RECEIVER

摘要

PURPOSE:To always attain the best tuning state by adjusting automatically an antenna tuning section with respect to a change in an antenna length in the mount state, to reduce the cost by reducing the adjustment process at the manufacture and repair and to improve the reliability without damage to components and defect in adjustment. CONSTITUTION:An AC/DC conversion section 13 converts an output signal of a radio section 3 into a DC signal corresponding to the amplitude of the signal and comparators 101-104 convert the converted DC signal into a 4-bit digital signal corresponding to the amplitude and outputs the signal. An output control section 16 controls transfer gates 109-113 based on the digital signal and a clock signal from a signal control section 9 to give a control voltage to varactor diodes 204-206 thereby bringing the best tuning state to the antenna tuning.