TheArchive/mayhem-firmware
1
0
Fork 0
mirror of https://github.com/portapack-mayhem/mayhem-firmware.git synced 2025-11-15 06:23:07 +00:00
Code Issues Packages Projects Releases Wiki Activity

Updated Audio Receivers (markdown)

Brumi-2021
2025-03-25 22:06:48 +01:00
parent 64c2132414
commit 7535e7e999
1 changed files with 4 additions and 3 deletions
Download Patch File Download Diff File Expand all files Collapse all files

7
Audio-Receivers.md

@@ -50,12 +50,13 @@ The Key Items on the App that can be seen or selected with the cursor and change
* **Gain:** The RF Amp settings. The Spectrum view is +/-20k.
* **USB+FM:** It is usually 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 ).
For a correct demodulation ,currently we need to tune that published frequency , (in our application , you do not need to apply any usual - 1.900Khz offset . The -tuning offset , is already applied internally). So we have to just tune the (published) Wefax Station frequency directly .
Note : All AM modes and AMFM mode has the option to expand x2 , the waterfall , selecting ZOOM x1/ZOOM x2
Here in that Audio App we can tune , and RECORD the APT signal into file.wav ,mainly for investigation and check signal levels (signal strenght , saturation , filters check , debugging). But we have also another external receiver Wefax App , more convenient to the user, that combines both things : (that APT demodulation and the additional display weather map to the LCD (in low resolution) or records the receiver map into bmp file (in full resolution.)
![image](https://github.com/user-attachments/assets/de140ed5-bbc9-4aa4-b775-4e7cae36ead0)
![image](https://github.com/user-attachments/assets/58acad5c-5abe-4b2b-858f-eb8aed06a228)
![image](https://github.com/user-attachments/assets/6fa91268-405c-46bd-9a7a-ed1dff001ef5)
![image](https://github.com/user-attachments/assets/58acad5c-5abe-4b2b-858f-eb8aed06a228)
* **WFM:** There are three option filters in that Secondary settings :