| 摘要 |
<p>PURPOSE:To detect the voltage waveform of a signal flowing on a communication line with fidelity by providing a means provided with a function to generate a capacitance value approximated to coupling electrostatic capacitance generated between an unbalanced type communication line that is a line targeted to be monitored and an electrode between the electrode and the ground, and attaching external electrostatic capacitance for compensation which performs band compensation. CONSTITUTION:A compensation conductor 2 is the one to supply the coupling electrostatic capacitance CC equivalent to the coupling electrostatic capacitance CC generated when the line 1 targeted to be monitored is sandwiched with the electrode 3 between the electrode 3 and the ground 6. The external electrostatic capacitance 4CE for compensation to be attached is electrostatic capacitance to be attached fixedly to further expand a low frequency band area. When the coupling electrostatic capacitance CC by the compensation conductor 2 is attached, flat loss is generated extending over a high frequency area, however, a flat part is extended in a low frequency area, which enables the making of the area into a wideband area. The increment of the loss in the flat part can be sufficiently amplified at a high input impedance differential amplifier, which remarkably increases the effect of compensation. When the external electrostatic capacitance 4CE for compensation is attached at the outside, the flat part in the low frequency area can be further expanded. A balanced type communication line can be set similarly as the line targeted to be monitored other than the unbalanced type communication line.</p> |
