声卡数字频率计 PC中的声卡不仅能输出和录制各种音频信号，利用其内部的A/D（模拟/数字）转换器，通过编写程序还可以用来对外部的周期性的模拟信号进行采样，并计算出该信号的频率值。文中所述的作者设计的程序就是这样的一种程序，能够满足一般电子爱好者把PC作为数字频率计使用的要求。该程序是标准的Windows界面，界面友好，以黑色背景红色大号字体显示频率值，具有醒目、程序简洁和测量精度高的特点，-sound card number or frequency of PC sound card can not only output and recording audio signals, use its internal A/D (analog/digital) converter, through the preparation process could also be used to the cyclical external analog signal is sampled, and the calculated value of the frequency signal. Wen described the author of the design process is one of the procedures, to meet the general electronic enthusiasts use the PC as a digital frequency meter use requirements. The procedure is the standard Windows interface, the interface is friendly to the black background of red font tuba frequency, with catchy and simple procedures and high measurement accuracy characteristics,