功能：频率计。具有4位显示，能自动根据7位十进制计数的结果，自动选择有效数据的 --高4位进行动态显示。小数点表示是千位，即KHz-Features: frequency meter. With four shows that will automatically count 7 the results of the metric system to automatically select a valid data - 4 high-dynamic show.