JPH05340768

PURPOSE:To further suppress the excessive response of the pointer of a cross- coil type meter against temporary fluctuation of the surface of a fuel liquid. CONSTITUTION:The driving current corresponding to the terminal voltage Vc of a capacitor is supplied to one cross coil 4a of a cross-coil type indicating instrument 4 through an impedance converter 1 and feeding transistor 2. When the surface level fluctuation of a fuel liquid is relatively large, a charging switch 8 or discharging switch 9 is maintained in a turned-on state and a common switch 10 is turned on for the period of 2msec at every 10 seconds by means of a charging/discharging time setting circuit 13. As a result, the capacitor 3 is charged or discharged during the 2-msec periods only under a constant- current condition. When the fluctuation is relatively small, the switch 8 or 9 is maintained in a turned-on state and the switch 10 is turned on for the period of 0.5msec at every 10 seconds by means of the circuit 13. As a result, the capacitor 13 is charged or discharged during the 0.5-msec periods only under a constant-current condition.