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在水文遥测自动测报系统中，采集的水文数据常常应用超短波无线通信技术进行数字传输，因此需要进行二进制数据的调制解调工作。ＭＣ１４４１２系完全用数字方法的专用集成芯片完成数字调制的，并可解调移频键控（ＦＳＫ）信号，集调制解调于一身。其电路设计时在带通滤波器与解调器之间增加了一级锁相环（ＰＬＬ）电路、减少了码元的抖动，提高了ＦＳＫ信号的输入质量，从而大大提高了ＭＣ１４４１２解调器的解调可靠性。
In the automatic hydrological telemetry system, the collected hydrological data are often transmitted by digital wireless communication technology using ultra-shortwave, so the need for binary data modulation and demodulation. The MC14412 is a complete digital modulation of a digital integrated ASIC and demodulates the FSK signal and combines modulation and demodulation. The circuit design adds a first-order phase-locked loop (PLL) circuit between the band-pass filter and the demodulator to reduce the jitter of the symbol and improve the input quality of the FSK signal, thereby greatly improving the MC14412 demodulator The demodulation reliability.