Roger, Markus, Marco, VLF,
This is a nice day, isn't it? ;-)
I have placed that message directly in the daily QRN minimum :-)
Before transmitting i applied the additional earth rods. Now there are 20 earth
rods at each pole and the overall resistance decreased from 1 kOhm to 650 Ohm!
The todays antenna current was 325 mA, so about 70 W TX power (still out of 3x
12 V / 7 Ah batteries). The S/N was about 10 dB, as Markus said. The trace was
even visible in DFCW-60, slightly.
In the next tests i will try to reduce the losses to somewhat arround 300 Ohm.
Then, i want to increase the wire length to about 600m, maybe even more (in
steps). This should give a signal increase of about 10 dB. Adding another 10 dB
by applying 500W and reducing to 1 mHz FFT on a day with some 2...3 dB lower
QRN COULD make the signal visible on Markus grabber in a distance of 175 km!
This is my goal with this antenna.
Additionally it would be nice to try something with a full size lambda/2 dipole
for 137 kHz. What do you think about that? 2x 1000m. No problem there on the
hill, hi :-)
As you know my "time constants" on realising such projects are rather small you
know that we know soon whats possible there ;-)
Roger,what about your QTH? Don't you have the possibility to arrange a 10x
longer wire than currently as well? The LF/VLF ham density seems to be much
higher there in the UK!? So you would get a quick feedback even on the dreamers
band.
73 and TNX,
Stefan/DK7FC
________________________________
Von: [email protected] im Auftrag von Roger Lapthorn
Gesendet: Sa 26.06.2010 12:52
An: [email protected]
Betreff: Re: LF: DK7FC's DFCW600 8.97kHz transmission NOW
Stefan,
I wonder how strong the signal would have been on a RX loop rather than the
E-field probe? This would be worth checking.
73s
Roger G3XBM
On 26 June 2010 11:50, Roger Lapthorn <[email protected]> wrote:
73 - the first message proper on the Dreamer's Band Stefan?
Kind regards
Roger G3XBM
On 26 June 2010 11:25, Roger Lapthorn <[email protected]> wrote:
Stefan,
The trace on the screen is very clear. I can see "7" very clearly on
your grabber followed by the start of the next symbol. Time now 1025z.
73s
Roger G3XBM
--
http://g3xbm-qrp.blogspot.com/
http://www.g3xbm.co.uk <http://www.g3xbm.co.uk/>
http://www.youtube.com/user/g3xbm
G3XBM GQRP 1678 ISWL G11088
--
http://g3xbm-qrp.blogspot.com/
http://www.g3xbm.co.uk <http://www.g3xbm.co.uk/>
http://www.youtube.com/user/g3xbm
G3XBM GQRP 1678 ISWL G11088
--
http://g3xbm-qrp.blogspot.com/
http://www.g3xbm.co.uk <http://www.g3xbm.co.uk/>
http://www.youtube.com/user/g3xbm
G3XBM GQRP 1678 ISWL G11088
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