| 摘要 |
PURPOSE:To increase the accuracy for the ease of observation, by achieving easy change of the period of noise voltage waves repetitively caused and of the frequency of the noise voltage waves having the number selected for the waves. CONSTITUTION:A sinusoidal wave variable frequency oscillaor 30 is connected to a circuit section via a plug 32. A wave shape circuit 34 consists of a comparator or a Schmitt trigger, converts a sinusoidal wave from the oscillator 30 into a rectangular wave, and a pulse counter 38 counts it to output a specified pulse width and a period selected with switches SW1-SWn. The counter consists of flip-flops in multi-connection and the output is obtained by suitable combination. Further, by operating a polarity switching circuit 36 consistig of exclusive OR circuits, the polarity of output is inversed and if the output is obtained from the leading or trailing is selected. |
