| 摘要 |
PURPOSE:To improve measuring efficiency through omitting the switching operation of an input coupler by alternately switching an input signal and a ground level and displaying them on a cathode-ray tube. CONSTITUTION:When an input coupler 2a is set in a ground mode, electronic switchs 13a, 14a are driven by a dividing circuit 16 to which an output of a channel changeover driving circuit 8 is applied, and a ground level plus a no signal level are displayed alternately on a cathode-ray tube 12 via a channel changeover gate 7 and a delay line 10. At this time, an offset voltage correcting circuit 15a that subjects the control of validity or invalidity by the switch 14a is adjusted to cause both levels to be made coincident. When the input coupler 2a is set in a DC mode, signal waveforms of the ground level and channels 1, 2 are alternately indicated. By this way, when the voltage value of a signal waveform is measured, time caused by setting an input coupler to ground is omitted. |
