| 摘要 |
<p>PURPOSE:To correctly measure a communication terminal disturbing wave voltage of a communication equipment having terminals for 4 communication lines or over by employing a current probe so as to measure a current flowing between a core wire and ground and obtaining a disturbing wave voltage from the current. CONSTITUTION:A series circuit comprising a capacitor C1 and an impedance element Z1 is connected between ground 17 and core wire connecting a communication line terminal and a communication line 15, a common mode choke coil 23 having almost no less with respect to a normal mode current by having a large loss with respect to common mode current is inserted between the series circuit and the communication line 15, and a current probe 25 measuring a disturbing wave corresponding to a disturbing wave voltage is inserted between the communication line terminal and the series circuit. Thus, the disturbing wave voltage of the communication line terminal is obtained by the measured value of the common mode current flowing to the circuit between the communication line 15 and ground 17. Thus, a communication line terminal disturbing wave voltage for a communication equipment having terminals for 4 communication lines or over is measured correctly.</p> |
