A signal generator based on NE555 and 74ls123 was designed, which will be used as LD modulation signal.
为了LD调制信号的需要，文章设计了基于NE555和74ls123的信号发生器。
2
The output of PWM(pulse width modulation)was automatically adjusted by TL494 to control the field current of the generator, which accomplished stabilizing output v.
通过TL494自动调节PWM输出控制励磁电流，达到稳定发电机输出电压、输出电流和限流充电的目的。
3
The waveform generator is composed by DSP and quadrature digital upconverter (QDU). DSP is used as main controller to decide the modulation mode and output waveform of QDU.