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Re: LF: RE: Summer games / EARTH ANTENNAS

To: [email protected]
Subject: Re: LF: RE: Summer games / EARTH ANTENNAS
From: Roman <[email protected]>
Date: Thu, 05 Jul 2018 22:45:13 +0300
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Russian forum about baloon ant:

http://136.su/index.php/topic,388.msg21646.html#msg21646

Roman

> Mmmm. Kite antennas are for summer ;-)
> 
> Have a look at this technique. Mixing Kite aerodynamics with hellium lift-off 
> push you get a real stable system to keep a wire up for long time and
> 
> dealing with wind. Probably not cheap, I’m afraid. They have a distributor in 
> DL
> 
> http://www.allsopp.co.uk/index.php?mod=page&id_pag=58
> 
> 73 de Luis
> 
> EA5DOM
> 
> De: [email protected] 
> [mailto:[email protected]]
> En nombre de DK7FC
> 
> Enviado el: martes, 03 de julio de 2018 23:42
> 
> Para: [email protected]
> 
> Asunto: Re: LF: RE: Summer games / EARTH ANTENNAS
> 
> Hi Marcin,
> 
> Keep us informed about your experiments. For you it may be more useful to try 
> kite antennas! Give it a try, it is very easy a nd exciting!
> 
> For power generation i used such a cheap generator:
> https://www.amazon.de/dp/B000QD1EHY/
> 
> For 500W it was running quite well, until i made the mistake to mix the oil 
> and fuel BEFORE filling it into the tank.
> 
> It is cheap and not very high quality but it is possible to carry it on your 
> own, which was essential for my kite experiments.
> 
> If you want quality, then by a Honda generator...
> 
> 73, Stefan
> 
> Am 03.07.2018 21:26, schrieb Marcin:
> 
>> Hello Stefan!
>>
>> From my experience, erth dipole work best on 630m. Unfortunately, in the 
>> north of Poland, the soil is well or very conductive. In rocky ground you 
>> can get much better results.
>> I am waiting for autumn to continue my experiments.
>>
>> https://klubnl.pl/wpr/en/index.php/2018/01/09/most-na-wisle-elementem-anteny-czyli-eksperymentow-z-dipolami-ziemnymi-ciag-dalszy/
>>
>> https://klubnl.pl/wpr/en/index.php/2017/11/26/kolejne-proby-z-antena-dipol-ziemny/
>>
>> I am looking for a power generator for power supply in the field.
>> Can anyone recommend something?
>>
>> 73! Marcin SQ2BXI
>>
>> From:
>> [email protected]
>> <[email protected]>
>> On Behalf Of DK7FC
>>
>> Sent: Tuesday, July 3, 2018 7:50 PM
>>
>> To: [email protected]
>>
>> Subject: LF: Summer games / EARTH ANTENNAS
>>
>> Hi Joe, VLF,
>>
>> You seem to like to 'play' on the very low frequencies during the sunny days 
>> :-)
>>
>> Same here! My YL bought a house in JN39XI and we are spending almost each 
>> weekend there in the peaceful silence. The forest is really great! I guess 
>> you know that, as a Canadian.
>>
>> Now i'm planning to receive some signals in
>> JN39XI07 . BTW a most useful distance for analysing my own signals from 
>> Heidelberg (about 55 km QRB).
>>
>> Oh and i think about playing with earth antennas again, you know!
>>
>> BTW did someone (of the group) ever tried to build a full size dipole for 
>> 137 kHz? I mean for transmitting! On a stony mountain/hill it could be 
>> better than expected. With a Raspi + GPS module one could build up a simple 
>> WSPR beacon and a ICL7667, which can
>> be driven by the 3.3 V GPIO output voltage could make a simple and effective 
>> 5W PA running at 12V.
>>
>> The wire just needs to be 1000m long or so. In a low frequented forest it 
>> could lay there for some days...
>>
>> I remeber experimenting with a full size dipole on 630m in 2012, when the 
>> band was quite young. It worked well although the antenna was just 4m above 
>> the ground and the soil conductivity was not ideal (medium conductivity). A 
>> few CW QSOs were done out of a
>> 7 Ah gel battery and just 50W or so, in July!
>>
>> And what about VLF and ULF using earth antennas? I remember making 45 km 
>> distance on 8.97 kHz from the 700m long wire antenna, grounded at each end 
>> (250W RF power if i remember correctly). That was about 15 dB in 3.8 mHz. 
>> But what would be possible on lower
>> frequencies if the far end of the wire is well grounded?
>>
>> Time to fill that summer hole (activity)!
>>
>> 73, Stefan
>>
>> Am 03.07.2018 14:03, schrieb [email protected]:
>>
>>> This was the first time SAQ was heard here using a mobile RX. It was in a 
>>> quiet location, a km from mains lines and other RF pollution. SAQ became 
>>> quite weak when
>>>
>>> the RX was in the forest however. The trees must be good conductors at VLF.
>>>
>>> Is the low-power miniwhip mentioned below the same new one designed with
>>>
>>> help from G4COL with a J310, Rs= 47-270 ohm and the FT-37-43 xfmr? I'd like
>>>
>>> to try that at VLF.
-- 
73!
Roman, RW3ADB

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