Hello Stefan
I was prompted to take a look 'down low' a couple of weeks ago when
SM5LE said, look 'Schumann resonances'. You will be surprised that I am
using your E-Probe, unmodified. I wasn't expecting to see much so I was
surprised by the results.
Have I seen Schumann resonances? I am not going to say, proof needs time
of observation.
Information about the signals and phenomena down there is scarce, I have
heard mention of 90Hz for submarine comms so many thanks for the link I
have removed my LPF and shifted the window up to take a look on 82Hz.
EDIT
Carrier at 80.2Hz, 75.2Hz and 64.24Hz which would seem to be a harmonic
of the 32Hz and likewise the 16Hz a sub harmonic of 32Hz.
My searches for information have certainly taken me to Renato's page, I
was showing a link to his site as a 8.9kHz Grabber, since looking at his
site I have moved him into a Link class of his own.
There have been questions about the pulses of interference at ULF. When
we look at our VLF Wide displays the Sferics seem to peter out around
3kHz, (your filter is doing its job). However I have used the 0....50Hz
view to prove to my own satisfaction that Sferics are still going strong
down to 0Hz. Probably removing the 3kHz cut of would cause havoc down there.
There are several carriers of unknown origin, maybe due to my urban
location which I can investigate. Any thoughts of what runs at 32Hz
would be welcome, I am pretty sure it comes down from the antenna. Well,
when there are no tests on 8.9kHz I can keep interested.
73 Eddie
On 04/05/2011 12:14, Stefan Schäfer wrote:
Hello Eddie, VLF,
Your additional grabber windows are interesting. Remembers me to the
site of Renato Romero ;-)
What antenna do you use for displaying the range of 0...50 Hz? My
probe circuit has a high pass filter with an edge frequency of about 3
kHz. So if your QRM below 3 kHz is not to strong, you may remove that
and get better signals on ELF. Have you ever received the ZEVS at 82
Hz? http://www.vlf.it/zevs/zevs.htm
73, Stefan/DK7FC
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