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Hi Rik
In a french book called "Poste 85" describing the beginning
of the electronics era during WW1 (telephone, radio, gonio, etc) , it is said
that it was possible to listen to enemy telephone conversations by putting some
rods in the ground and connecting them to a 3 triodes amplifier (the return
audio ground current of the wire telephones were strong enough to allow
conversations spying)
Jean-Louis F6AGR
Hello Stefan,
what about "going underground".
I do remind
an article on communication via some kind of ground antennas in the WW1 (or
WW2 ?) trenches (I guess it wasn't very convenient to put up antennas within
the sight of the enemy).
If I recall it right quite low frequencies were
used.
Googling on "ground antenna war" resulted in this : http://www.rexresearch.com/rogers/1rogers.htm
73, Rik ON7YD - OR7T
At 10:32 22/02/2010, you wrote:
Hello Horst,
That sounds really nice. If it would be
easy to find some motivated OMs in the near field (31km) ;-), that would be
an interesting field to test.
Yesterday i
have thought about possible antenna configurations for that range and got
the idea that one could use a forrest as an antenna tower. There, you could
hang up 100s meters of wire, in series and in parallel. You do not need to
have that area beside your house. Nobody will see the wire and nobody will
care about it.
Since summer 2007 i have a horizontal loop antenna
mounted in some trees on my hill with excellent results on all HF bands and
also 160m. The loop has 130m and is mounted up to 12m above ground. Perfect
matching from 160m to 10m with my symmetric tuner. I even tried matching on
2200m without a problem but with bad ODX results, of course. But if one
would try 2x 10*100m on VLF, the ODX would be
interesting...
JO30OT is abt 160km from JN49IS and thus a
little far i think ;-)
What is your RX antenna and have you
already catched some commercial VLF stations in that range? Are there
some?
73, Stefan
PS: One can be sure that there
will never be SSB operation ;-)
Von: [email protected] im
Auftrag von Horst Stöcker
Gesendet: Mo 22.02.2010
09:29
An: [email protected]
Betreff: RE: LF:
AW: Beaconing on 8.79 kHz in QRSS
Hallo
Stefan,
there was a notice in Funkamateur 12/05, S. 1287, that in DL
the range <9kHz is free.
I could not believe that so I asked the
BNetzA and after a while I got a letter which confirmed that.
So
there nothing you've got to do for getting a licence. You do not need
one.
There is no limitation of technical parameters like bandwith or
power.
Hard to believe in german, but obviously true.
My QTH
is Siegburg
JO30OT
Horst
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