Hello José,
OK, but if you live in a city, brobably it is better to try a small E
field antenna first. Daniele Tinacani has done many tests with loops
and E field antennas on 9 kHz. Maybe he can give some further advice
(if he reads this mail).
It would be worth to monitor a wideband screen to see which kind of
noise affects the RX. Some EMC tricks may improve things easily by 20
dB, depending on the source and path of the noise. You can find these
by testing, e.g. trying a battery instead of a normal power supply,
trying a battery fed notebook instead of a normal PC, trying to ground
(or not) the antenna either on the RX or antenna side, using an audio
transformer to decouple an earth loop, rising the antenna by 2m (to
reduce the gain and improve the wanted signal strength) and and and :-)
I remember these works and email exchanges by 4X1RF, TF3HZ, G3ZJO and
others. All they have gained a lot after seeing and experimenting where
the noise comes from. So the wideband screen is essential i mean...
73, GL,
Stefan/DK7FC
Am 14.06.2011 23:28, schrieb josé manuel:
Hello Stefan,
My idea is to use the PC as VLF RX
under 10 kHz. I think that the level noise increased in my urban
environment because I don´t copy the Alpha´s transmissions now,
however I could copy them some years ago, when I worked on 137 kHz.
I´ll try to improve my provisional antenna system, perhaps with a loop
I can reject some of the "made man noise" :-) I´ll tell you about the
experiences.
73 de José, EA1PX
-----
Original Message -----
Sent:
Tuesday, June 14, 2011 12:18 PM
Subject:
LF: VLF in Spain
Hello José,
OK. Do you already have a receiver for VLF? If so, which one? The PC's
soundcard? Or do you just guess that you have strong QRM?
Many stations are in the city, like 4X1RF, SQ5BPF and me. Anyway there
is good reception, 4X1RF even at above 2500 km! Others are in the
countryside and have never really got good reception, so mostly its an
EMC issue.
Thus i would suggest to built a suitable antenna and run a suitable
software and monitor the total spectrum of your soundcard input which
is mostly 0...24 kHz, often called "wideband". You can see these
windows running on many grabbers such as
http://www.mydarc.de/df6nm/vlf/vlfgrabber.htm
http://www.ok2bvg.cz/vlfgrabber/
http://qsl.net/4x1rf/yo/vlfgrabber.htm
http://simnet.is/halldorgudmunds/TF3HZ_VLFgrabber/index.html
http://www.iup.uni-heidelberg.de/schaefer_vlf/DK7FC_VLF_Grabber.html
and many others.
Then, you'll get immediately an impression of the actual situation and
see effects like mains hum, sferics and the Alphas system and some MSKs.
Seeing the Alphas and the sferics (i.e. the gap arround 8...11 UTC) is
a first good indicator for sensitivity!
Actually all you need is a few Euros to build that RX antenna which can
be a loop or a E field antenna. Mosty receptions were done with the E
field antennas which have some advantages due to their low weight and
volume. But loop antennas have shown very good results as well, mostly
in quiet locations (like Paul Nicholson, F4DTL, M0BMU...).
73, Stefan/DK7FC
Am 14.06.2011 00:08, schrieb Jose Manuel:
Stefan,
I´ll try to do some experience
on sub 9kHz reception; I´ll try to find a quiet location on holiday,
because I live in a very noisy urban environment.
Regarding 137 kHz I had some
2-way QSO´s in the past with your country, with Wolf, Markus and
others, but currently my LF antenna is down and I need to repair the
SLM as well.
73 de José, EA1PX
-----
Original Message -----
Sent:
Monday, June 13, 2011 11:42 PM
Subject:
Re: LF: ZEVS tonight.jpg
Josè,
You can get many informations about the Dreamers Band (<9) at G3XBMs
sub 9 kHz website: https://sites.google.com/site/sub9khz/
Here you find record lists and advice for antennas. And you can get
every information needed HERE! :-)
73, Stefan/DK7FC
Am 13.06.2011 23:30, schrieb Jose Manuel:
Mal and all,
You know that reception on 9
kHz is much more difficult than on 137 kHz.
I never tried to receive
below 10 kHz, perhaps in a couple of weeks, when I´m on holiday ;-)
73, José, EA1PX
-----
Original Message -----
Sent:
Monday, June 13, 2011 7:53 PM
Subject:
Re: LF: ZEVS tonight.jpg
Jose
In the past you were able
to copy me on CW no problem, with XBAND qso
de mal/g3kev
-----
Original Message -----
Sent:
Monday, June 13, 2011 4:14 PM
Subject:
Re: LF: ZEVS tonight.jpg
Hi Stefan and all,
I´m in the NW of Spain,
locator IN53ti, but with a very long path with you ;-)
73 de José, EA1PX
-----
Original Message -----
Sent:
Sunday, June 12, 2011 11:57 PM
Subject:
Re: LF: ZEVS tonight.jpg
Eddie,
Where in France will you be? http://no.nonsense.ee/qthmap/
:-)
Will you be RX QRV on LF/VLF? If you are in the south, this would be an
interesting region. Unfortunately there is nothing yet from Spain on
VLF...
QRN will be high i assume so maybe it wouldn't be easy. Anyway iz would
be worth a try. BTW i just checked for wind and the next weekend looks
promising so far. If it will hold on, i'll try a kite VLF experiment
but still much can change until then...
73, Stefan/DK7FC
Am 12.06.2011 23:27, schrieb qrss:
Hello Nicolas
Yes almost 100% transmissions at 0800 and 1700UTC.
Each data element is 4min and there are 6 of those plus 'start' and
'space' makes 8 total, 32 minutes then the final long carrier 'stop' is
1 Hour.
Good luck with the antenna, yes urban noise is the big problem. Soon I
will come to France to try some really quiet places, I look forward to
that.
73 Eddie G3ZJO
On 12/06/2011 21:34, [email protected]
wrote:
Henny, Eddy beautifull captures.
It's every day at the same hour ? 0800 and
1700 UTC ?
How long the ZVES transmissions ?
I built an new VLF antenna and I'll start soon
receptions.I would be in campaign to reduce urban noise.
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