(1)设计4位十进制频率计测量范围: 1Hz～9999Hz

(2）测量的数值通过4个数码管显示

(3）频率超过9999Hz时，溢出指示灯亮，可以作为扩大测量范围的接口-(1) the design of four decimal frequency measuring range: 1Hz ~ 9999Hz (2) measurement values through four digital tube display (3) the frequency of more than 9999Hz, the overflow indicator light can be regarded as measuring the expansion of the scope of the interface