| 摘要 |
PURPOSE:To secure the monitoring for the transmission output regardless of the reception level by securing a sufficiently large amount of attenuation for the reception signals to be divided into the direction of the transmission monitor circuit via the hybird circuit and against the attenuation of the transmission signals to be divided in the same way. CONSTITUTION:The output signal of transmission circuit 1 is amplified 2 and then applied to hybrid circuit 8. The part of the output of circuit 8 is sent to transmission monitor circuit 3, and the other part is sent to hybrid circuit 5 each. Then the output signals of circuit 5 are delivered to the line via line filter 6 and insulation transformer 7. While the reception signals supplied via transformer 7 and filter 6 are divided at circuit 5 to be supplied to reception circuit 4 as well as to circuit 8. And the reception signals divided furthermore in circuit 8 are sent to amplifier 2 and circuit 3. Here a sufficiently large amount is secured for the attenuation of the reception signals to be divided into the direction of circuit 3 against the attenuation of the transmission signals to be divided in the same way. As a result, the transmission output can be monitored regardless of the reception level. |
