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# AM Demodulation Demo

Recover a message from an AM signal one stage at a time. Choose the **Envelope Detector** or the **Synchronous Detector** at the top, then switch each stage on to see what it does to the signal.

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    <span>Interactive demo · AM Demodulation · Lesson 30</span>
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## Things to Try

- **Build the envelope detector.** Turn on the diode, the LPF, and the HPF one at a time. Compare the final output with the message you started with.
- **Over-modulate.** Raise $A_m$ above the bias $b$ so that $\alpha > 1$. What does the envelope detector recover now?
- **Switch detectors.** Send the same over-modulated signal through the synchronous detector and compare the result.
- **Check the frequency domain.** Use the Frequency Domain tab to see which components each stage removes.