@Bernd: Congratulations for your receiver, Bernd! Works nice, and I suppose that in that “green” field you are far away from electric and EM interferences. Good job!
In my location, I have many problems with switching power supplies, different inverters, etc.
Look here how bad was the local VLF spectrum in the morning, at the 1st SAQ transmission:
I put a digital edited MP3 with the content of the 1st SAQ transmission here .
Fortunately, I had slightly good conditions at the 3rd SAQ transmission:
and screenshot #2:
For this session, I didn’t make any digital edit.
I also tried to receive with the miniWhip connected to the soundcard, using Spectrum Lab.
Look at the images below (click on them to enlarge):
The captured audio from the soundcard session is here:
Record #1
Record #2
I know that is not much, but considering the perturbations around, I am OK with what I done today.
Hope that the next time will be better !
Regards from Bucharest,
Cezar YO3FHM