The input is a voltage signal mixed with high-frequency and low-frequency sine wave signals. Design a circuit system so that the circuit can separate the high-frequency signal and the low-frequency signal, and perform amplitude modulation processing separately, and synthesize the processed signal (the specific parameters of the device do not need to be given, but the device used is a non-ideal device, Need to be able to meet the actual situation). Claim: (1) Write out design ideas and design ideas; (2) Draw the circuit diagram.