Diode FM Crystal Radio

Diode FM Crystal Radio.
Many people ask how can a simple crystal radio performs Frequency demodulation.
You can read this article that explains "The Slope Detection Method for FM radio".
https://www.electronics-notes.com/art...

Here is my own over-simplified understanding. A Slope Detection Circuit uses a High Q resonant circuit to turn an FM signal to an AM signal, which can then be detected by a diode from a simple crystal radio. Just think of it this way. The FM modulation will shift the frequency of the carrier wave from one frequency to the next based on the wave form of the original speech or music (aka the source signal). If you have a very high Q resonant circuit, the FM modulated signal will appear to be tuned in (loudest) or tuned out (softer) as the frequency of the carrier wave varies or modulates according to the source signal. Hence the output of the resonant circuit is similar to that of an Amplitude modulated signal. Hence it can be detected by simple circuit such as a single Diode. This detection has many flaws, as it's only a restore the partial signal from the original broadcast. The audio produced out of this are usually not clear enough unless you have a very strong signal, or has a high performance detector for weak signals, e.g. 3DQ to replace the Diode.