The signal generator is also called signal source or oscillator, which is widely used in the production practice and science and technology field. Various waveform curve can be represented by trigonometric function equation. It can also generate many waveform, such as triangular wave, sawtooth wave, rectangular wave, sine wave, etc. Signal generator has a widely usage in the experiment of circuit and equipment detection. For example, in the system of communication, broadcast and television, if you want to carry the video signal or pulse signal out, you need the signal generator which can generate the high frequency. In the field of industry, agricultural and biomedicine, such as the high-frequency induction heating, smelting, hardening, ultrasonic diagnosis, MPI, etc, the high or low frequency signal generator are all needed.