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Hi
Rik,
I think that I
must have omitted something.
The blue barrel
is the 277 mhy not counting the coils on top of the
barrel.
Total L was 345
mhy which was too much and forced operation to 8890Hz
Still this is
close to 1 nF
No not yet I did
not try radials yet and will make this step soon
For some reason the
bridge I made for 9Kz is not working, that needs to be
fixed.
Then I can
experiment with ground radials rods etc.
PauLC
W1VLF
Hello Paul,
congrats on your achievement.
Based on L = 0.277H and f = 8890Hz the antenna
capacitance is 1.16nF. You must have an impressive amount of wire up
in the air.
Regarding "ground" : did you try
radials ?
73, Rik ON7YD
Markus
Valued
commentary as always. Plans are to continue making improvements in the
station.
What are your
feeling about the ground at 9 KHz?
Currently I am
using 3 2 meter ground rods spaced 2 meters apart and 1
meter distant from the concrete basement wall of my
shack.
This setup is
not optimum I understand and was never intended to be final ground system for
my regular ham station.
As a very quick
and crude test I pounded an aluminum pole into the earth 2 meters deep near
the 9 KHz coil.
When this was
connected to the existing ground there was a very small increase in the
current meter.
Antenna system
impedance here is about 1250 Ohms with and antenna current of approx.
200 ma.
Lots of work to
do!!!
I will make
another post on grounds to the group as well.
Thank
you
PauLC
W1VLF
Dear Paul and Jay,
this is an excellent result, well done!
The crossover between reactive nearfield
(E ~ r^-3) and farfield (r^-1) occurs at lambda/2/pi = 5.3
km. As you seem to have quite a bit of margin there, your signal
will be detectable very significantly beyond that. Assuming
otherwise equal receive conditions, QRSS-120 should get you more than 6
times further than QRSS-3.
Best wishes,
Markus (DF6NM)
----- Original Message -----
Sent: Friday, April 16, 2010 8:05
PM
Subject: Re: LF: Dreamers Band update
from W1VLF
Paul,
Great
work! Nice looking coil! How much power can you crank through
it?
At 5kM, I believe that you are still in the near field
(9kHz
wavelength is 33km), so signal will fall off at the 3rd power
of
distance until you reach far-field conditions.
--
73
Warren
K2ORS
WD2XGJ
WD2XSH/23
WE2XEB/2
WE2XGR/1
at 1:51 PM, Paul A. Cianciolo <[email protected]> wrote:
> Hello
Folks,
>
> Today we made our first outdoor transmission on
VLF.
>
> The system resonance forced the transmissions to take
place on 8890 Hz at
> least until I can get a variometer worked
up.
>
> The distance is only 5 KM but the signal is quite good
on QRSS3.
>
> I can only wonder how far the signal would go
using QRSS 120???
>
> Please comment if you can, this a great
learning experience for me
>
> Thank you
>
>
PauLC
> W1VLF
>
> http://www.rescueelectronics.com/9-Kilohertz.html
>
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