| 摘要 |
PURPOSE:To prevent the generation of a switching noise, by giving a gentle variation during changeover of antennas to a received signal sent from an antenna to be separated as well as to a received signal sent from an antenna to be newly connected to a receiver. CONSTITUTION:If a multipath reception arises at an antenna A1 when a diode D1 conducts to supply a signal sent from a receiving antenna A1 to a receiver, the input signal of the receiver lowers. Thus a control signal e1 changes from L to H level, and at the same time a control signal e2 changes from H to level, respectively. The rise and fall of the outputs of inverters I1 and I2 are integrated by a capacitor C1 and a resistance R1, and the DC voltage that turns on the diode D1 reduces gently. The voltage increasing gently is applied to a diode D2. As a result, a swtiching noise which is caused by the rise and fall of a signal during changeover of antenna can be prevented. |
