Hello Paul,
Also congrats to the QRSS3 5km distance! :-) Who is the next station that can
receive your signal?
1nF / 345mH sounds very good! 1250 Ohm, is that the overall (loss) resistance?
If not, how much power do you have to apply to get the 200mA and how do you
measure the current?
Have you tried to connect your house mains to the VLF earth? I would try that!
;-) If the current increases with house earth connected to the system, try to
reduce the power so that I is 200mA again and check, if your signal is as stong
as before (at the RX side) to check if the radiation resistance was reduced by
this step. Again choosing the same power than in the QRSS3 QSO will show the
antenna efficiency change...
Your coils look good on the photos! I would estimate that the coils can stand
at least 50kV rms. Paul, you have to make QRO after checking who could be the
next receiving station, hi ;-)
Wish you good luck and fun!
BTW: Do you have a good VLF / Dreamers band/ RX? As you know, i will try to get
this 300m vertical permission! I already have the confirmation of my insurance
;-)
Stefan / DK7FC
________________________________
Von: [email protected] im Auftrag von Paul A. Cianciolo
Gesendet: Sa 17.04.2010 16:54
An: [email protected]
Betreff: RE: LF: Dreamers Band update from W1VLF
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
-----Original Message-----
From: [email protected]
[mailto:[email protected]]On Behalf Of Rik Strobbe
Sent: Saturday, April 17, 2010 10:30 AM
To: [email protected]
Subject: RE: LF: Dreamers Band update from 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
________________________________
Van: [email protected]
[[email protected]] namens Paul A. Cianciolo [[email protected]]
Verzonden: zaterdag 17 april 2010 15:53
Aan: [email protected]
Onderwerp: RE: LF: Dreamers Band update from W1VLF
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
-----Original Message-----
From: [email protected]
[mailto:[email protected]]On Behalf Of Markus Vester
Sent: Friday, April 16, 2010 4:29 PM
To: [email protected]
Subject: Re: LF: Dreamers Band update from 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 -----
From: Warren Ziegler <mailto:[email protected]>
To: [email protected]
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
>
<<winmail.dat>>
|
