Hi VLF friends,
Nice to see there is some interest again in the very low frequencies :-)
Yesterday i checked the VLF spectrum in my graden for the first time. I
tried to detect ZEVS and took a 2 hour recording from 0...24 kHz. The
antenna was a multi turn loop pointing to N/S.
Unfortunately the results are relatively disappointing. There is still
a lot of QRM from the tram (DC, 12 pulse rectifier) which is in just
400m distance.
This is the recording:
https://dl.dropboxusercontent.com/u/19882028/VLF/Garten%20VLF1%20bis%20173_31UTC%20am%2002092014.WAV
and here is a spectrogram showing 0...500 Hz over the recording period:
https://dl.dropboxusercontent.com/u/19882028/VLF/VLFwideGarten0bis500.jpg
So far i did not run a reprocessing and i didn't use noise blanking.
Maybe something will be visible when adding some filtering.
Anyway, at least the spectrum from 0...24 kHz looks much cleaner than
in the city.
Next i want to try an E field antenna. This could be more promising.
73, Stefan
PS: Thanks for the ZEVS grabbers by Eddie and Halldór.
Am 03.09.2014 00:45, schrieb Markus Vester:
Hi Eddie, LF group,
it looks like despite very strong 50
Hz and 16.7 Hz harmonics, I can still receive useful ELF signals from
my Marconi (currently only 3 m above the roof) with a simple BF245
source follower. The top panel of my VLF grabber http://www.df6nm.de/vlf/vlfgrabber.htm currently
shows the ZEVS carrier, as well as several Schumann resonances.
Best 73,
Markus (DF6NM)
Sent: Tuesday, September 02, 2014 11:14 AM
Subject: Re: LF: RE: ZEVS question
As part of my checking that everything is OK and ready for the next
tests on ELF/ULF/SLF ? I have my Grabber
http://www.g3zjo.talktalk.net/vlfgrabber.htm
Live on Wide and ZEVS. ZEVS is showing a good carrier at this time in
my
urban environment.
73 Eddie G3ZJO
On 28/08/2014 13:43, DK7FC wrote:
> Hi ELF ;-) (actually it is ULF!)
> https://dl.dropboxusercontent.com/u/19882028/VLF/spectrumusage.jpg
>
> Unfortunately ZEVS seems to be offöine in the moment, at least
TF3HZs
> grabber does not show a trace.
>
> 73, Stefan
>
> Am 27.08.2014 23:47, schrieb DK7FC:
>> Hello Halldór,
>>
>> That is very nice! Thanks. I will save the site on my
smartphone so i
>> can check it from the garden :-)
>>
>> Best 73 to Iceland.
>>
>> Stefan
>>
>> Am 27.08.2014 23:34, schrieb Halldór:
>>> Stefan,
>>>
>>> I have been monitoring the ZEV´s just for fun. The current
status is a
>>> steady carrier on 82Hz so a good chance to test your
equipment
>>> Two transmissions a day, morning and evening
>>> You can watch my reception on
>>> http://simnet.is/halldorgudmunds/TF3HZ_ZEV/
(not a permanent page)
>>>
>>> and some recent noise-free receptions on my regular vlf
page.
>>>
>>> Have fun,
>>>
>>> 73
>>> Halldór
>>>
>>> -----Original Message-----
>>> From: [email protected]
>>> [mailto:[email protected]] On Behalf Of
DK7FC
>>> Sent: 27. ágúst 2014 19:46
>>> To: [email protected]
>>> Subject: LF: ZEVS question
>>>
>>> Hi VLF experts,
>>>
>>> Some of you received ZEVS in the past. Could someone tell
me when
>>> ZEVS is on
>>> air? Is it every morning? Which settings are ideal for the
reception
>>> (scroll
>>> rate? FFT bin width?). What is the location of ZEVS?
>>>
>>> I would like to try to receive it from the garden tomorrow
or the
>>> weekend...
>>>
>>> 73, Stefan
>>>
>>>
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