18dB loss applies only to the near field (induction) loss I think.
73s
Roger G3XBM
Sent from my iPod Touch 4g
On 19 Nov 2010, at 22:05, Gerhard Hickl <[email protected]> wrote:
> Hi Stefan!
>
> At least at my site, QRM/QRN was pretty low this day and so rather the
> (too) wet soil could be the reason for your weak signal.
>
> I watched you grabber and when I saw you were "only" 40db oN on your
> DFCW6000 window (4-5km), I had no hope to copy your signal here at
> 594km!
>
> BTW: Do you think it is true that we can assume 18db Loss for twice the
> distance?
>
> 73
> OE3GHB
> Gerhard
>
>
> Am Freitag, den 19.11.2010, 19:32 +0100 schrieb Stefan Schäfer:
>> Hi Gary, VLF,
>>
>> OK, nothing received this time, not even by Paul Nicholson. A pity.
>> But it was shown that Micheal Oexner clearly received the signal at
>> 250W in DFCW-600 (before some weeks) so it must have been about 10 dB
>> stronger at 100W and 141 µHz. So there must have been other reasons
>> why there was no reception. Maybe the wet soil is still a disadvantage
>> or the QRM was just to high.
>> I will not give up on the earth antenna but maybe it makes more sense
>> to try more power and a faster mode in shorter distances first. Maybe
>> i will arrange a RX at my parents QTH in 36 km distance...
>>
>> Its time to make an new kite experiment. If the wind will be fine, i
>> will do it next weekend. Before i want to arrange a 3rd tap on the
>> coil for 300m @ 8970 Hz. And i am highly interested to drive this
>> antenna on 137 kHz :-)
>>
>> Thanks to all for taking part at the yesterdays test and building up
>> RX and Grabbers! :-)
>>
>> 73, Stefan/DK7FC
>>
>> PS: After the test, the PA, SMPS, netbook, car, antenna and the forest
>> is well up! Batteries were discharged to 9 V ;-)
>>
>>
>>
>> Am 19.11.2010 16:32, schrieb Gary - G4WGT:
>>> Hello Stefan,
>>>
>>>
>>> Nothing here up to the sound card crashing about midnight.
>>>
>>>
>>> 73
>>>
>>>
>>> Gary - G4WGT
>>>
>>>
>>> On 19 November 2010 11:03, "Jean-Pierre Méré (F1AFJ)"
>>> <[email protected]> wrote:
>>> Hi Stefan ,
>>>
>>> Nothing here ! I listening 20:00 to 07:00 today
>>>
>>> 73 Jean-Pierre f1afj
>>>
>>> Le 19/11/2010 11:50, [email protected] a écrit :
>>>
>>> Not a trace Stefan,sorry,
>>>
>>> 73
>>> Victor
>>>
>>> -----Oorspronkelijk bericht-----
>>> Van: [email protected]
>>> [mailto:[email protected]]Namens
>>> Stefan Schäfer
>>> Verzonden: vrijdag 19 november 2010 10:15
>>> Aan: [email protected]
>>> CC: Paul; Bernd Grupe
>>> Onderwerp: Re: VLF: Long time transmission on earth
>>> antenna
>>>
>>>
>>> Dear VLF,
>>>
>>> It seems these batteries are not in best condition.
>>> The carrier got
>>> weaker and weaker in the morning and disappeared
>>> arround 5 UTC.
>>>
>>> The SMPS that drives the PA is designed to generate
>>> its own 15 V supply
>>> once it started to run. But if the input voltage
>>> falls below 10V (or 9)
>>> it shuts down. Seems that this has happend... The
>>> batteries have> 300
>>> Ah in sum so it should have been no problem,
>>> actually...
>>>
>>> I assume no one except me has detected anything?
>>>
>>> BTW: The starting time was 15:30 UTC so the DFCW
>>> shift appeared at 23:30 UTC
>>>
>>> 73, Stefan/DK7FC
>>>
>>>
>>>
>>> No virus found in this incoming message.
>>> Checked by AVG - www.avg.com
>>> Version: 8.5.449 / Virus Database: 271.1.1/3265 -
>>> Release Date: 11/18/10
>>> 19:34:00
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>>>
>
>
>
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