| 摘要 |
<p>The present invention includes an active filter (3) employed in a receiver and band-adjusting by a control voltage, a first adjustment resistor (51) connected between a control terminal (11) and a power terminal (6), a second adjustment resistor (52) connected between the control terminal (11) and ground, and an external power supply (13) selectively connected to the control terminal (11) and whose output voltage can be adjusted stepwise. First, the external power supply (13) is connected to the control terminal (11), and the output voltage of the external power supply (13) is changed stepwise. Further, the receive sensitivity of the receiver is measured each time the output voltage is changed, and the output voltage of the external power supply (13) at the acquisition of the highest receive sensitivity is detected. Next, the external power supply (13) is disconnected from the control terminal (1), and the connections of the adjustment resistors (5152) are controlled or adjusted so that the voltage at the control terminal (11) becomes substantially equal to the detected output voltage. <IMAGE></p> |
