...and if its the glass Coca Cola Bottle - they are used "professionally" in Africa and some other parts of the world as base/side insulators in even some Government HF/MF systems :-)
Laurence KL7UK
Not so sunny Wasilla Alaska
> From: [email protected]
> To: [email protected]
> Date: Fri, 10 Jun 2011 19:58:30 +0100
> Subject: Re: LF: Re: First tests on VLF at DK7FC in Heidelberg
>
> PET - Polyester - is a recognised capacitor dielectric, and not particularly
> lossy.
> I don't see why it shouldn't work - as long as you drink the cola first.
> 73
> Hugh M0WYE
>
>
> ----- Original Message -----
> From: "mal hamilton" <[email protected]>
> To: <[email protected]>
> Sent: Friday, June 10, 2011 6:11 PM
> Subject: Re: LF: Re: First tests on VLF at DK7FC in Heidelberg
>
>
> > Stefan
> > Using LOSSY coca cola bottles as a dielectric is not recommended and poor
> > stability makes things worse!!!!!!!!!
> > With this information I do not think a QSO is possible
> > de mal/g3kev
> >
> > ----- Original Message -----
> > From: "Stefan Schäfer" <[email protected]>
> > To: <[email protected]>
> > Cc: "Paul" <[email protected]>; "Bernd Grupe"
> > <[email protected]>
> > Sent: Friday, June 10, 2011 5:36 PM
> > Subject: Re: LF: Re: First tests on VLF at DK7FC in Heidelberg
> >
> >
> > After a break i am back on air in this moment transmitting a long
> > carrier. The signal generator is the DDS VFO, so stability is not
> > perfect but should be suitable for 424 uHz i hope. It is a very first
> > test.
> >
> > When using the antenna wire with maximum L i currently have available,
> > the resonance is at 9.64 kHz, not to far away. I built a capacitor out
> > of 2 aluminium plates and 2 coca cola bottles and come to resonance now
> > on 8970 Hz. Before is used the bottles, i used stones. But they became
> > HOT and later there was a black hole into them sparking around! These
> > losses reduced the antenna power to less than 200 mA. Now i have about
> > 500 mA antenna current and will transmit a longer dash until i see some
> > traces on the grabbers, hopefully.
> >
> > When running the system without external addional C, so on 9.64 kHz, i
> > am getting 360 mA antenna current at 80 W PA input power. The coil
> > losses are 320 Ohm so the sourrounding losses seem to be about 300 Ohm
> > which is not to much, thinking about trees and buildings...
> >
> > Now, i'll TX for some time, maybe 2 hours ort so.
> >
> > Any reports so far?
> >
> > 73, Stefan/DK7FC
> >
> >
> > Am 10.06.2011 15:00, schrieb mal hamilton:
> >> Stefan
> >> My monitor is running/Speclab dfcw600 es Antenna 150 metre inv L up over
> > 33
> >> metres vertical. Condx all bands Good at present
> >>
> >> de mal/g3kev
> >>
> >> ----- Original Message -----
> >> From: "Stefan Schäfer"<[email protected]>
> >> To:<[email protected]>
> >> Cc: "Paul"<[email protected]>; "Bernd Grupe"
> >> <[email protected]>
> >> Sent: Friday, June 10, 2011 1:02 PM
> >> Subject: Re: LF: Re: First tests on VLF at DK7FC in Heidelberg
> >>
> >>
> >> Hello Mal, VLF,
> >>
> >> OK, i am actually RX QRV on LF all the time here. And i have internet
> >> during the test! :-)
> >>
> >> Now, the coil is on the roof and it's dry. I will prepare now... Maybe
> >> the first VLF antenna current in a 20 minutes...
> >>
> >> 73, Stefan/DK7FC
> >>
> >>
> >> Am 10.06.2011 09:53, schrieb mal hamilton:
> >>
> >>> Stefan
> >>> I will leave my monitor on 8970 DFCW 600 mode. If I detect your signal I
> >>> will reply on 137.7 CW or QRS3.
> >>> 73 De Mal/G3KEV
> >>>
> >>> ----- Original Message -----
> >>> From: "Stefan Schäfer"<[email protected]>
> >>> To:<[email protected]>
> >>> Cc: "Paul"<[email protected]>; "Bernd Grupe"
> >>> <[email protected]>
> >>> Sent: Thursday, June 09, 2011 8:09 PM
> >>> Subject: VLF: First tests on VLF at DK7FC in Heidelberg
> >>>
> >>>
> >>>
> >>>
> >>>> VLF,
> >>>>
> >>>> Tomorrow i plan to do first tests on 8970 Hz on my fixed antenna in
> >>>> Heidelberg,
> >>>> http://no.nonsense.ee/qthmap/?qth=JN49IK00WG&from=jn49ik00WD It is
> >>>> about
> >>>> 30m up.
> >>>>
> >>>> I'll start doing some resonating tests and may come on air in the
> >>>> afternoon. The small PA (max. 300W) will be used in this first test
> >>>> since it is easier to manage. Maybe the resonance will be some kHz
> >>>> higher but i hope to come down into the Dreamers Band (TM).
> >>>>
> >>>> I expect to be visible on "local" grabbers like DF6NM, OE3GHB and
> >>>> OK2BVG. If all works well i plan to transmit a longer dash, maybe 6000
> >>>> seconds and later a short message in DFCW-600, like "K" or so, just for
> >>>> the proof and to get a first impression about the efficiency of this
> >>>> antenna.
> >>>>
> >>>> I had the idea to buy some flexible aluminium tube to form a toroid
> >>>> that
> >>>> will be placed on the top of the coil. Tis reduces the maximum E field
> >>>> and adds some C, that might be needed to come down to 8970 Hz...
> >>>>
> >>>> Of course all this depends on the absence of rain but now i don't need
> >>>> wind! Therefore, the signals will be about 20 dB lower, probably.
> >>>>
> >>>> The signal will be overload my grabber
> >>>> http://www.iup.uni-heidelberg.de/schaefer_vlf/DK7FC_VLF_Grabber.html
> >>>> that is in about 20 m (!) distance. Hopefully it gets not damaged due
> >>>> to
> >>>> several 10 kV on the wire.
> >>>>
> >>>> Is there someone who will watch for that signal?
> >>>>
> >>>> Reports would be very apprechiated!
> >>>>
> >>>> 73, CU, Stefan/DK7FC
> >>>>
> >>>>
> >>>>
> >>>
> >>
> >>
> >
> >
> >
>
>
=
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