| 摘要 |
PURPOSE:To avoid the change in feedback loop gain for in single and parallel connection, by adding the 2nd feedback loop only when two amplifying sections are in parallel connection. CONSTITUTION:A feedback loop consisting of a feedback circuit 8 is provided from an output coupling circuit 4 to an input coupling circuit 2 in addition to a main feedback loop consisting of a feedback circuit 6, and this feedback loop is operated only when amplifying sections 3 and 3' are in parallel connection. Thus, in case of a single connection, the feedback loop by the feedback circuit 8 can not be constituted. Through a suitable setting of the 2nd feedback loop by the feedback circuit 8, the increment of the gain at parallel connection of the amplifying sections can be absorbed, allowing to prevent the increase in the gain of the main feedback loop at parallel connection. |
