| 摘要 |
PURPOSE:To measure with high precision against change of frequency over a wide range, by controlling the period of a gate circuit by a control circuit and by setting its gate open time to a prescribed value. CONSTITUTION:When a start signal is applied from input terminal 2 to control circuit 3, control circuit 3 executes a preset program. Then, gate circuits 4 and 11 are brought under the period control of control circuit 3 and their gate open time T2 ends at the point that corresponds to the period of some order of a pulse signal to be measured satisfying the relation T2>=T1 (timer operation time). As a result, counter circuits 5 and 12 count the number of pulses of the pulse signal to be measured having passed through the gates and the number of clock pulses respectively with accuracy. This constitution to measure frequencies over a wide range up to a high frequency with high precision as well as a low frequency. |
