| 摘要 |
PURPOSE:To enable to sensitively response to a rapid change in frequency, by a method wherein a pulse to be measured is measured in a sampling time T and a sampling time T' being shorter than the sampling time T, and the two counting values are added. CONSTITUTION:A pulse signal to be measured from a terminal (a) is inputted to a counter 14 through an AND circuit 11, whose gate is opened by a sampling pulse from an oscillator 12. Meanwhile, a gate of an AND circuit 21 is opened by means of a dividing output generated by a dividing circuit 22 for an output of an oscillator 12, and the pulse to be measured, passing therethrough, is inputted to a counter 24. The counting values of counters 14 and 24 are stored in memories 15 and 25, the stored data in the memory 15 are inputted as data of higher digit to a D/A converter 18, and the stored data in the memory 25 as data of a lower digit to the converter 18. Based on the converted output, an indicator 20 is actuated. This causes a rough counting value to be displayed rapidly, and then, permits the display of an accurate counting value. |
