声频信号源不仅要求具有一般信号源的特性,而且要求它的频率复盖范围很宽,通常的解决方法采用差拍振荡器,它可产生20Hz 到20kHz 连续变化的频率信号。作为信号源要求的频率稳定度高,非线性失真小,以工作方式上进行连续扫描等,差拍部分过去用两个 LC 振荡器的输出信号进行混频,取其差频信号。这种振荡器的缺点是频率稳定度低,同时体积也大。 Not only does the audio signal source require the characteristics of a typical signal source, but it also requires a wide frequency coverage. The usual solution is a beat oscillator, which produces continuously varying frequency from 20Hz to 20kHz. As the signal source requirements of high frequency stability, nonlinear distortion is small, continuous scanning on the way to work, the beat part of the past two LC oscillator output signal mixing, whichever difference frequency signal. The disadvantage of this oscillator is its low frequency stability and its large size.