| 摘要 |
PURPOSE:To operate only either one of an existing radio transmission outputting circuit and a spare radio transmission outputting circuit, by providing a switching element, a DC feedback circuit and a matching circuit. CONSTITUTION:An existing radio device transmission outputting circuit 2 is fed from a power supply terminal 1 via a relay contact 9-1, and a switching element 10-1 is made to a low impedance by flowing a DC current in the path of DC limit resistor 5 relay contact 9-2 switching element 10-1 DC feedback circuit 11-1 and mathcing is perfrmed with a matching circuit 12-1. As a result, the transmitted output of a transmission output circuit 2 is transmitted from an antenna 6 with low loss. If the transmission output level is lower or interrupted, a relay circuit 8 via a transmission output detecting circuit 7 actuates the relay contacts 9-1 and 9-2 at the same time and switching is made to a transmission output circuit 3. Thus, the output of the circuit 3 can be transmitted to the antenna 6 with low loss in the same way as mentioned above. |
