这样可以使检波器获得足够大的信号，从而使整机输出音质较好的音频信号,，所以中频调谐放大电路可以做到选择性好、增益高又不易自激。这样灵敏度和选择性都可大幅度改善，而且可使整个波段接受灵敏度均匀!-This allows the detector to obtain a large enough signal, so that the overall output quality better audio signal, so the IF amplifier circuit can be tuned selectivity, high gain and easy to self-excited. This can greatly improve the sensitivity and selectivity, sensitivity and make the whole band accepted uniform!