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
>
