| 摘要 |
PURPOSE:To perform an easy automatic control for the transmission level in the automatic equalizing system for the loss frequency characteristics of the transmission line, by connecting one end of the 1st and 2nd veriable resistance elements each to the reference potential point to secure the common control for them. CONSTITUTION:When the resistances of the cable transmission lines are referred to as R11-R16 with the capacity to C respectively, voltage gain G(f) is shown by equation 1-(3). The right half side of the equation functions as part of the flat control, and the gain becomes maximum when variable resistance R12 is infinite. And then the gain reduces as the resistance value decreases. On the other hand, the latter half of the equation shows the slope gain in that the gain in the low frequency region is low when variable resistance R15 is infinite and then the gain increases as the frequency increases. Here one end of resistances R12 and R15 each is connected to the earth functioning as the reference potential point to be controlled in common along with the control directions made identical to each other. Thus an easy automatic control is performed for the transmission level. |
