Roger,
Thanks for the tip on the papers.
I downloaded the NATO AGARD paper from the NATO ftp site:
ftp://ftp.rta.nato.int//PubFullText/AGARD/CP/AGARD-CP-529/AGARDCP529.pdf
Beware that it is 42MB and the server is slow!
--
73 Warren K2ORS
WD2XGJ
WD2XSH/23
WE2XEB/2
WE2XGR/1
On Mon, Feb 22, 2010 at 9:11 AM, Roger Lapthorn <[email protected]> wrote:
> It was NATO AGARD papers (not AGAARD) that I was referring to.
>
> Here are some other useful references to ULF/VLF system design and
> practicalities:
>
> <http://ieeexplore.ieee.org/xpl/freeabs_all.jsp?reload=true&arnumber=1138037>
> <http://oai.dtic.mil/oai/oai?&verb=getRecord&metadataPrefix=html&identifier=AD0640319>
> <http://www.search.com/reference/Ultra_low_frequency#Earth_Mode_Communications>
>
> 73s
> Roger G3XBM
>
> On 22 February 2010 10:03, Roger Lapthorn <[email protected]> wrote:
>>
>> At this frequency, widely spaced, grounded electrode pairs are probably
>> the best "antenna". There are references to how these work in the
>> literature (for example NATO AGAARD papers from the 1960s, available on the
>> internet I believe) and on one of the German ham sites (DK8KW) - see
>> http://www.qru.de/#vlf ;.
>>
>> Don't expect great ranges: up to 10kms is a fair aim with modern signal
>> processing technology and reasonable (amateur levels) available power.
>> Project Sanguine achieved worldwide coverage to submarines at 76Hz (yes
>> Hertz!) but used enormous power and antennas stretching for 100s of kms.
>>
>> 73s
>> Roger G3XBM
>>
>>
>> 2010/2/22 Stefan Schäfer <[email protected]>
>>>
>>> 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
>>> ___________________________________________________________
>>> NEU: Mit WEB.DE DSL über 1000,- ¿ sparen!
>>> http://produkte.web.de/go/02/
>>>
>>>
>>>
>>
>>
>>
>> --
>>
>> http://g3xbm-qrp.blogspot.com/
>> http://www.g3xbm.co.uk
>> http://www.youtube.com/user/G3XBM
>> G3XBM GQRP 1678 ISWL G11088
>
>
>
> --
>
> http://g3xbm-qrp.blogspot.com/
> http://www.g3xbm.co.uk
> http://www.youtube.com/user/G3XBM
> G3XBM GQRP 1678 ISWL G11088
>
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