Updated Audio Receivers (markdown)

Audio-Receivers.md

@@ -43,6 +43,7 @@ The Key Items on the App that can be seen or selected with the cursor and change
     * **NFM:** Bandwidth Settings of 16k,11k,8k5. Note there is no setting for the more common 6k5 used in European Spectrum plans. Next item is SQ: which is shown in the format of 40/99 allow the noise squelch point to be set Between 0-99. Typically, around 40-50 is a good threshold.
     * **Gain:** The RF Amp settings. The Spectrum view is +/-20k.
     * **USB+FM:** It is used to demodulate Wefax (HF Weather fax transmissions) , demodulating the signal in two steps,  first demodulating the tuned  RF signal in USB , extracting audio tones. And then demodulating again those FM modulated subcarrier audio tones,  to extract APT low scan weather fax map signal. (that signal can be recorded into audio.wav file . Still current  mayhem fw can not decoded the picture -we need external programs, but coming soon, please wait ...) 
+For a correct demodulation , we need to tune that published frequency applying negative offset (- 1.900Khz) , tuning  and aligning  the top max freq. "white" carrier (published) with top part aligned with top "yellow" mark, , as the following drawing,
 
      ![image](https://github.com/user-attachments/assets/3b76e009-d64f-495f-8976-1858502248ec)
          ![image](https://github.com/user-attachments/assets/58acad5c-5abe-4b2b-858f-eb8aed06a228)