Hi VLF,
There was a SID, well visible on various VLF grabbers. While propation
above 15 kHz was greatly improved, it looks like the noise levels below
9 kHz rather dropped. I wonder what signal a phase changes could be been
observed on my signal?
One day i will be on air while this happens so we can get a bit more
understanding of what happens below 9 kHz.
Another interesting thing is that the QRM arround 9 kHz in the wideband
spectrogram at RC4HAA (http://www.136.su/grabber/) dropped as well. So
it could be that it is not local QRM (e.g. from a power supply in the
neighbourhood) but rather a strong signal on MF/HF that still passes the
low pass filter. That means the situation can be improved by a better
filtering... Should be tried :-)
73, Stefan
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