Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by klubnl.pl (8.14.4/8.14.4/Debian-8+deb8u2) with ESMTP id x18EMlp2032077 for ; Fri, 8 Feb 2019 15:22:55 +0100 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1gs6xf-0004dt-W6 for rs_out_1@blacksheep.org; Fri, 08 Feb 2019 14:16:59 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1gs6xf-0004dk-24 for rsgb_lf_group@blacksheep.org; Fri, 08 Feb 2019 14:16:59 +0000 Received: from mout01.posteo.de ([185.67.36.65]) by relay1.thorcom.net with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.91) (envelope-from ) id 1gs6xb-0002k7-6m for rsgb_lf_group@blacksheep.org; Fri, 08 Feb 2019 14:16:57 +0000 Received: from submission (posteo.de [89.146.220.130]) by mout01.posteo.de (Postfix) with ESMTPS id 18DB516005E for ; Fri, 8 Feb 2019 15:16:52 +0100 (CET) X-DKIM-Result: Domain=posteo.de Result=Signature OK DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=posteo.de; s=2017; t=1549635413; bh=/XlbqbDi/V4VsIoFrfPJ2BDy3kissBMPNUX/QpgxqQk=; h=Date:From:To:Subject:From; b=Hv3AXBe83PoKIEOyUxIL/3bVyMSHKbqRb0Pb99ta/uySPQPh87QQRaGPnsHpKe0lj cLfSEy8kFi7tTDN820vEeCX9Fdvrg0s+1q/nUZdBysLYxW0720n1H0U9/oBSyErR69 Q4mH9fZwtNvOFvV4KaT+0ExRiTQXn6ThsrGM4zAFzJZzXgnzY78H7p2ixw+NLNeufK bElsVud2bSZfd5VgdekGDJCMNPXn+eBsvvlPN6pracTSkBebuwwQb64FhgBtq21O+G fzu7aybX1ipWzasAUpLYueQbgBvGlS/EJoORNtaYpx+jhZBcDMv1vwHR3z5duY+wVX iase8jIAci7dg== Received: from customer (localhost [127.0.0.1]) by submission (posteo.de) with ESMTPSA id 43wy102LwQz6tmG for ; Fri, 8 Feb 2019 15:16:51 +0100 (CET) Message-ID: <5C5D8F53.1080409@posteo.de> Date: Fri, 08 Feb 2019 15:16:51 +0100 From: DK7FC User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; de; rv:1.9.1.8) Gecko/20100227 Thunderbird/3.0.3 MIME-Version: 1.0 To: rsgb_lf_group@blacksheep.org References: <168c41b89f6.marcocadeddu@tin.it> <5C5BE905.2010904@posteo.de> In-Reply-To: X-Spam-Score: -2.3 (--) X-Spam-Report: Spam detection software, running on the system "relay1.thorcom.net", has NOT identified this incoming email as spam. The original message has been attached to this so you can view it or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: Hi Dimitris, Am 07.02.2019 22:59, schrieb Dimitrios Tsifakis: > You must have a much larger antenna than me as in my current 140 m^2, > 3-turn loop, I can reach a bit over a 1 uW with a 1 kW input! On which freque [...] Content analysis details: (-2.3 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -2.3 RCVD_IN_DNSWL_MED RBL: Sender listed at http://www.dnswl.org/, medium trust [185.67.36.65 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record 0.0 HTML_MESSAGE BODY: HTML included in message X-Scan-Signature: 13abe497adcf17a4e25c5e2a2ff79111 Subject: Re: VLF: in VK? Content-Type: multipart/alternative; boundary="------------050200080201040503040504" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.5 required=5.0 tests=HTML_MESSAGE,HTML_TITLE_EMPTY autolearn=no version=2.63 X-SA-Exim-Scanned: Yes Sender: owner-rsgb_lf_group@blacksheep.org Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group X-SA-Exim-Rcpt-To: rs_out_1@blacksheep.org X-SA-Exim-Scanned: No; SAEximRunCond expanded to false This is a multi-part message in MIME format. --------------050200080201040503040504 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Hi Dimitris, Am 07.02.2019 22:59, schrieb Dimitrios Tsifakis: > You must have a much larger antenna than me as in my current 140 m^2, > 3-turn loop, I can reach a bit over a 1 uW with a 1 kW input! On which frequency? Didn't you tell about a 120m x 3m single turn loop? > There > are many physical limitation that cannot be exceeded that will never > allow me 200 uW with this antenna. Of course, that's just the start, > once I get some success, I will be looking for larger antennas (and I > do have some ideas which extend past my fence). One of the first steps could also be to place a receiver in the far field, a good receiver. You are working in Canberra, right? So you can place a RX there and make a webpage showing spectrograms? Ah BTW are you skilled with Linux or do you arlready know that you'll never give it a try? > You know the > addiction! > Hehe, yes! I already looked arround in your location. It is a QTH for dreamers! You know the history about the 'DREAMERS'? ;-) What is that stuff in QF44OX02XI ? Is it water? Or there in QF44OX01US ? Water, that is water! Horray!! There you could throw some wire into, your aluminium wire. Oh and here in QF44NW99XV That's excellent! There is just a little effort and you will be able to leave a trace on Edgars RX, TXing with 200 uW. If you can lay a wire from here to there, see http://k7fry.com/grid/?qth=QF44OX01US&from=QF44NW99XV that's 1000m already and you can get a good conductivity. Try to find metallic plates, maybe 1 sqare metre. That could work fine. 1 km is not so much, you could even roll it up again after transmitting. It would be interesting to see how much current you can get at DC or at various frequencies up to 30 kHz. > Anyway, my plan is to start at 29.999 kHz (the entrance to VLF!) > first. My antenna works a lot better on that frequency. I will them > move down in frequency. For the legal limit of 7.5 uW, what distance > would you expect a QRSS10 signal to cover at 29.99 kHz? We'll find out > this weekend but I can start taking bets today! :-) > If you have a well working RX, sensitive antenna, both H field, the right position and 'no' nearby QRM sources, it think you can make 10 km. That's my guess, without doing calculations. If you run 50 uW on 17.47 kHz (Edgar is skilled on that frequency!) you will reach Edgar, if your loop points into his direction. If you can run just 500 mA into that 1 km long wire, on that frequency, you will be there! Do you have enough wire for the weekend? :-) I use that cheap CCA loudspeaker cable which has 0.75 mm2. A 100m ring (i.e. 2x 100m) costs about 13 EUR here, quite affordable. 73, Stefan > 73, Dimitris VK2COW > --------------050200080201040503040504 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: 8bit Hi Dimitris,

Am 07.02.2019 22:59, schrieb Dimitrios Tsifakis:
You must have a much larger antenna than me as in my current 140 m^2,
3-turn loop, I can reach a bit over a 1 uW with a 1 kW input!
On which frequency? Didn't you tell about a 120m x 3m single turn loop?
 There
are many physical limitation that cannot be exceeded that will never
allow me 200 uW with this antenna. Of course, that's just the start,
once I get some success, I will be looking for larger antennas (and I
do have some ideas which extend past my fence).
One of the first steps could also be to place a receiver in the far field, a good receiver. You are working in Canberra, right? So you can place a RX there and make a webpage showing spectrograms?
Ah BTW are you skilled with Linux or do you arlready know that you'll never give it a try?

 You know the
addiction!
  
Hehe, yes!
I already looked arround in your location. It is a QTH for dreamers! You know the history about the 'DREAMERS'? ;-)
What is that stuff in QF44OX02XI ? Is it water? Or there in QF44OX01US ? Water, that is water! Horray!! There you could throw some wire into, your aluminium wire.
Oh and here in QF44NW99XV  That's excellent! There is just a little effort and you will be able to leave a trace on Edgars RX, TXing with 200 uW.
If you can lay a wire from here to there, see http://k7fry.com/grid/?qth=QF44OX01US&from=QF44NW99XV that's 1000m already and you can get a good conductivity. Try to find metallic plates, maybe 1 sqare metre. That could work fine. 1 km is not so much, you could even roll it up again after transmitting.
It would be interesting to see how much current you can get at DC or at various frequencies up to 30 kHz.

Anyway, my plan is to start at 29.999 kHz (the entrance to VLF!)
first. My antenna works a lot better on that frequency. I will them
move down in frequency. For the legal limit of 7.5 uW, what distance
would you expect a QRSS10 signal to cover at 29.99 kHz? We'll find out
this weekend but I can start taking bets today! :-)
  
If you have a well working RX, sensitive antenna, both H field, the right position and 'no' nearby QRM sources, it think you can make 10 km. That's my guess, without doing calculations.
If you run 50 uW on 17.47 kHz (Edgar is skilled on that frequency!) you will reach Edgar, if your loop points into his direction. If you can run just 500 mA into that 1 km long wire, on that frequency, you will be there!
Do you have enough wire for the weekend? :-) I use that cheap CCA loudspeaker cable which has 0.75 mm2. A 100m ring (i.e. 2x 100m) costs about 13 EUR here, quite affordable.

73, Stefan
73, Dimitris VK2COW

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