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 w15Jwo1J016017 for ; Mon, 5 Feb 2018 20:58:53 +0100 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1eimq7-0001f5-JR for rs_out_1@blacksheep.org; Mon, 05 Feb 2018 19:54:07 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1eimq6-0001ew-02 for rsgb_lf_group@blacksheep.org; Mon, 05 Feb 2018 19:54:06 +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 4.89) (envelope-from ) id 1eimq2-0002FQ-7E for rsgb_lf_group@blacksheep.org; Mon, 05 Feb 2018 19:54:04 +0000 Received: from submission (posteo.de [89.146.220.130]) by mout01.posteo.de (Postfix) with ESMTPS id 3CD4C2121E for ; Mon, 5 Feb 2018 20:53:59 +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=1517860440; bh=RrM437Hwt4JD3qsNnCgdeUNkals3hyCDutO+7XX2qOA=; h=Date:From:To:Subject:From; b=DG5P/pAYkBOl9WpNxbkboSdTyKmvFrDIqzAJBXR8bRpeKrgkfx0M3/f+Qb6GPZ1AB X3W7Pw7DmekghJ0mg3wVWfA+ZHj2lvoxPzD+YqeVSw3W03kqRvnJpzhRkKg6xFGo1b HnTo4JY4qcrfw8UrxGhrYyp1oLQmb/BQsBGNXX1M2vQtITHxPLxR/59Eo8LYnQIQcn hma9S2j+PCmhDHWRxenAo71nvCTG3rUqIGqGv3OTdrkKhoMOSqYzImD54jVrPTLBAu mXMaGpiBGWuLgXibUu608mN9U9l/bN0TrwoOz/QxYCSR05cSfv1eFYjB1gaYb4WrEA JKzjAWGEm9lwg== Received: from customer (localhost [127.0.0.1]) by submission (posteo.de) with ESMTPSA id 3zZyvl4nyHz9rxl for ; Mon, 5 Feb 2018 20:53:55 +0100 (CET) Message-ID: <5A78B653.7050401@posteo.de> Date: Mon, 05 Feb 2018 20:53:55 +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: <579355A36AEE9D4FA555C45D556003AB9AB485D3@servigilant.vigilant.local> <5A7377F7.4050802@posteo.de> <017101d39bab$2f0e3710$8d2aa530$@comcast.net> <23159F1ED5BD49AD9654CE5685AFACF6@Clemens0811> <5A75EA08.9090009@posteo.de> <579355A36AEE9D4FA555C45D556003AB9AB4958F@servigilant.vigilant.local> <5A78A2D6.7000407@posteo.de> In-Reply-To: X-Spam-Score: 0.0 (/) 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 Juan, Good luck with your tests. Do you have/need a special license for transmitting on that frequency or is it free for everyone unless you stay below a certain ERP level? Oh, i have another question: Did you try to receive on VLF from underground with your loop? Actually 38 kHz is still LF but it is the same equipment i think. I would be interested in a spectrogram generated from a loop RX operated under ground. A non-resonated loop. Right now i am transmitting on 970 Hz. That frequency will pass the soil and would reach an underground loop! But the power levels are not high enough here to pass the distance over to EA :-) [...] Content analysis details: (0.0 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 T_RP_MATCHES_RCVD Envelope sender domain matches handover relay domain 0.0 HTML_MESSAGE BODY: HTML included in message 0.0 T_DKIM_INVALID DKIM-Signature header exists but is not valid X-Scan-Signature: 21f1dd9e5d349c4603888a79aa965668 Subject: Re: LF: VLF Small magnetic antenna for Tx Content-Type: multipart/alternative; boundary="------------090600000708000608030000" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.1 required=5.0 tests=HTML_FONTCOLOR_UNSAFE, HTML_MESSAGE 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. --------------090600000708000608030000 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Hi Juan, Good luck with your tests. Do you have/need a special license for transmitting on that frequency or is it free for everyone unless you stay below a certain ERP level? Oh, i have another question: Did you try to receive on VLF from underground with your loop? Actually 38 kHz is still LF but it is the same equipment i think. I would be interested in a spectrogram generated from a loop RX operated under ground. A non-resonated loop. Right now i am transmitting on 970 Hz. That frequency will pass the soil and would reach an underground loop! But the power levels are not high enough here to pass the distance over to EA :-) I would expect there is no 'gain' from such a site, only some kind of low pass filter. This should not improve the SNR. But it would be interesting :-) 73, Stefan Am 05.02.2018 20:30, schrieb Juan Leandro Ronda: > Hi Stefan, > A piece is better. I have mixed copper and brass union nuts. The > reason is for the space it occupies when passing through underground > cavities, there are very narrow passages. I have not observed losses > in the inductance, but the MKP / FKP capacitors are heated and I have > a drift in the tuning. They have to go through them the 100A. In just > one turn, 85Vp is already produced. Now I am using capacitors NP0 in > SMD, it is incredible the behavior before the great tension and > amperage, they have the disadvantage of having limit of high values ​​ > of capacity. I want to perform a test with Luis orienting the loop to > his antenna, we are 49 km away, but he always has a lot of noise at 38KHz. > > Regards > Juan Leandro > > El 5 feb. 2018 19:33, "DK7FC" > escribió: > > Interesting. > I built a similar loop and transmitted on MF. The maximum power > was about 30 W RF because the resonating Cs (WIMA-FKP-1, 2kV) > became warm and the resonance drifted away. But i managed up to > 450 km distance with that compact antenna. > > You loop may become more effective when using a single piece of > copper. Don't you have such 'endless' tubes available? Like this > one: > https://www.hornbach.de/shop/Kupferrohr-weich-22-mm-Wandstaerke-1-mm-Meterware/3308518/artikel.html > > > 73, Stefan > > > Am 05.02.2018 15:13, schrieb Juan Leandro Ronda: >> I have to say that I am also lacking in theory, but the tests >> carried out on airborne and core coils have been successful and >> are working. >> The most relevant loop antenna has been an octagon-shaped loop, >> formed by 22mm diameter copper pipe of 1mm thickness, equivalent >> to 66mm square, forming a surface of 1m square. As seen in the >> attached diagram, I put in resonance by LC series (38400Hz) >> giving close to 100A, which in turn gives a magnetic moment of >> 100A per square meter. I verify that in the center of the octagon >> I am condensing enough the magnetic flux, knowing that it is very >> difficult to saturate the air. In summer I get to notice heating >> of the pipe. If I bring a euro coin to the pipe, it heats up and >> diverts the antenna's resonance. >> Then I was forced to reduce the volume of the antenna for >> comfortable use in underground cavities. I had to resort to using >> cores to keep an effective area as large as possible. I tried >> what I had at hand, the coils of the TV deflection coils and I >> observed good operation, I also circulated a large amperage for >> it, giving rise to the development of a new transmitter for >> radiolocation, it is the Summer, published in the CREG JOURNAL >> nº99 " of the BCRA. >> I have always wanted to use the power through low voltage and a >> lot of amperage, which will translate into great magnetic moment. >> It is necessary to use few loops in the loop, with a large >> section of the conductor and a high magnetic permeability core to >> increase the effective area. I also intend to minimize the >> tensions in the resonant circuit, there are partners who can >> suffer electrocution risk, since the equipment works at one >> hundred percent humidity and other times submerged. >> So far I have changed the cores of the air antennas for ferrites, >> and now I would like to use mu-metal that has very high magnetic >> permeability. I see hard to get that material. I have seen that >> they manufacture rods of several cm in diameter. It would be >> interesting to contact the manufacturer and ask for samples, if >> someone sees it feasible to say something about it. >> I have always worked in the near field for the use of >> radiolocation, and speaking with Luis EA5DOM, we discussed the >> effectiveness of using the electric field or the magnetic field >> with air, knowing that it is the magnetic that crosses the rocky >> pack more easily . I appreciate the comments on this part by this >> group. >> >> https://drive.google.com/folderview?id=1V4K2T2e3ActVqPaHr1xXLcjBkD16NtGB >> >> >> >> Regards >> Juan Leandro >> >> El 4 feb. 2018 8:35 p. m., "Juan Leandro Ronda" >> > escribió: >> >> I have to say that I am also lacking in theory, but the >> tests carried out on airborne and core coils have been >> successful and are working. >> The most relevant loop antenna has been an octagon-shaped >> loop, formed by 22mm diameter copper pipe of 1mm thickness, >> equivalent to 66mm square, forming a surface of 1m square. As >> seen in the attached diagram, I put in resonance by LC series >> (38400Hz) giving close to 100A, which in turn gives a >> magnetic moment of 100A per square meter. I verify that in >> the center of the octagon I am condensing enough the magnetic >> flux, knowing that it is very difficult to saturate the air. >> In summer I get to notice heating of the pipe. If I bring a >> euro coin to the pipe, it heats up and diverts the antenna's >> resonance. >> Then I was forced to reduce the volume of the antenna for >> comfortable use in underground cavities. I had to resort to >> using cores to keep an effective area as large as possible. I >> tried what I had at hand, the coils of the TV deflection >> coils and I observed good operation, I also circulated a >> large amperage for it, giving rise to the development of a >> new transmitter for radiolocation, it is the Summer, >> published in the CREG JOURNAL nº99 " of the BCRA. >> I have always wanted to use the power through low voltage and >> a lot of amperage, which will translate into great magnetic >> moment. It is necessary to use few loops in the loop, with a >> large section of the conductor and a high magnetic >> permeability core to increase the effective area. I also >> intend to minimize the tensions in the resonant circuit, >> there are partners who can suffer electrocution risk, since >> the equipment works at one hundred percent humidity and other >> times submerged. >> So far I have changed the cores of the air antennas for >> ferrites, and now I would like to use mu-metal that has very >> high magnetic permeability. I see hard to get that material. >> I have seen that they manufacture rods of several cm in >> diameter. It would be interesting to contact the manufacturer >> and ask for samples, if someone sees it feasible to say >> something about it. >> I have always worked in the near field for the use of >> radiolocation, and speaking with Luis EA5DOM, we discussed >> the effectiveness of using the electric field or the magnetic >> field with air, knowing that it is the magnetic that crosses >> the rocky pack more easily . I appreciate the comments on >> this part by this group. >> >> Regards >> Juan Leandro >> >> >> El 3 feb. 2018 21:35, "Jacek Lipkowski" > > escribió: >> >> On Sat, 3 Feb 2018, VIGILANT Luis Fernández wrote: >> >> Jacek, you mentioned what I was midnight oiling here >> " If you want some semi-DX in the H-field, then try >> coupling into some long >> conductors (pipes, power lines, railway tracks etc)" >> >> >> And i forgot phone lines :) >> >> Actually there has been a 700m phone line, that was well >> grounded at the phone exchange (old exchange, no local >> modules were used, so the wire went all the way there). >> This makes a nice ground dipole when a transmitter is >> placed between the local ground and the grounded wire >> from the phone line. Putting abt. 30mA at 8.97kHz (this >> was when 9kHz was the ITU limit) gave a very nice signal >> 600-700m from the phone line. >> >> >> What about coupling the loop to my 90m vertical ? >> Adding another transformer from loop to vertical or >> just winding some coils of the vertical over the >> small loop ring would work ? >> >> >> No, because the amount of current induced in the mast >> would be very small. >> >> BTW i wish i had a 90m vertical. >> >> >> VY 73 >> >> Jacek / SQ5BPF >> >> --------------090600000708000608030000 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: 8bit Hi Juan,

Good luck with your tests. Do you have/need a special license for transmitting on that frequency or is it free for everyone unless you stay below a certain ERP level?

Oh, i have another question: Did you try to receive on VLF from underground with your loop? Actually 38 kHz is still LF but it is the same equipment i think.
I would be interested in a spectrogram generated from a loop RX operated under ground. A non-resonated loop.
Right now i am transmitting on 970 Hz. That frequency will pass the soil and would reach an underground loop! But the power levels are not high enough here to pass the distance over to EA :-)

I would expect there is no 'gain' from such a site, only some kind of low pass filter. This should not improve the SNR. But it would be interesting :-)

73, Stefan

Am 05.02.2018 20:30, schrieb Juan Leandro Ronda:
Hi Stefan, 
    
   A piece is better. I have mixed copper and brass union nuts. The reason is for the space it occupies when passing through underground cavities, there are very narrow passages. I have not observed losses in the inductance, but the MKP / FKP capacitors are heated and I have a drift in the tuning. They have to go through them the 100A. In just one turn, 85Vp is already produced. Now I am using capacitors NP0 in SMD, it is incredible the behavior before the great tension and amperage, they have the disadvantage of having limit of high values ​​of capacity. I want to perform a test with Luis orienting the loop to his antenna, we are 49 km away, but he always has a lot of noise at 38KHz.

Regards
Juan Leandro

El 5 feb. 2018 19:33, "DK7FC" <selberdenken@posteo.de> escribió:
Interesting.
I built a similar loop and transmitted on MF. The maximum power was about 30 W RF because the resonating Cs (WIMA-FKP-1, 2kV) became warm and the resonance drifted away. But i managed up to 450 km distance with that compact antenna.

You loop may become more effective when using a single piece of copper. Don't you have such 'endless' tubes available? Like this one: https://www.hornbach.de/shop/Kupferrohr-weich-22-mm-Wandstaerke-1-mm-Meterware/3308518/artikel.html

73, Stefan


Am 05.02.2018 15:13, schrieb Juan Leandro Ronda:
    I have to say that I am also lacking in theory, but the tests carried out on airborne and core coils have been successful and are working.
The most relevant loop antenna has been an octagon-shaped loop, formed by 22mm diameter copper pipe of 1mm thickness, equivalent to 66mm square, forming a surface of 1m square. As seen in the attached diagram, I put in resonance by LC series (38400Hz) giving close to 100A, which in turn gives a magnetic moment of 100A per square meter. I verify that in the center of the octagon I am condensing enough the magnetic flux, knowing that it is very difficult to saturate the air. In summer I get to notice heating of the pipe. If I bring a euro coin to the pipe, it heats up and diverts the antenna's resonance.
Then I was forced to reduce the volume of the antenna for comfortable use in underground cavities. I had to resort to using cores to keep an effective area as large as possible. I tried what I had at hand, the coils of the TV deflection coils and I observed good operation, I also circulated a large amperage for it, giving rise to the development of a new transmitter for radiolocation, it is the Summer, published in the CREG JOURNAL nº99 " of the BCRA.
I have always wanted to use the power through low voltage and a lot of amperage, which will translate into great magnetic moment. It is necessary to use few loops in the loop, with a large section of the conductor and a high magnetic permeability core to increase the effective area. I also intend to minimize the tensions in the resonant circuit, there are partners who can suffer electrocution risk, since the equipment works at one hundred percent humidity and other times submerged.
So far I have changed the cores of the air antennas for ferrites, and now I would like to use mu-metal that has very high magnetic permeability. I see hard to get that material. I have seen that they manufacture rods of several cm in diameter. It would be interesting to contact the manufacturer and ask for samples, if someone sees it feasible to say something about it.
I have always worked in the near field for the use of radiolocation, and speaking with Luis EA5DOM, we discussed the effectiveness of using the electric field or the magnetic field with air, knowing that it is the magnetic that crosses the rocky pack more easily . I appreciate the comments on this part by this group.



Regards
Juan Leandro

El 4 feb. 2018 8:35 p. m., "Juan Leandro Ronda" <juanleronda@gmail.com> escribió:
    I have to say that I am also lacking in theory, but the tests carried out on airborne and core coils have been successful and are working.
The most relevant loop antenna has been an octagon-shaped loop, formed by 22mm diameter copper pipe of 1mm thickness, equivalent to 66mm square, forming a surface of 1m square. As seen in the attached diagram, I put in resonance by LC series (38400Hz) giving close to 100A, which in turn gives a magnetic moment of 100A per square meter. I verify that in the center of the octagon I am condensing enough the magnetic flux, knowing that it is very difficult to saturate the air. In summer I get to notice heating of the pipe. If I bring a euro coin to the pipe, it heats up and diverts the antenna's resonance.
Then I was forced to reduce the volume of the antenna for comfortable use in underground cavities. I had to resort to using cores to keep an effective area as large as possible. I tried what I had at hand, the coils of the TV deflection coils and I observed good operation, I also circulated a large amperage for it, giving rise to the development of a new transmitter for radiolocation, it is the Summer, published in the CREG JOURNAL nº99 " of the BCRA.
I have always wanted to use the power through low voltage and a lot of amperage, which will translate into great magnetic moment. It is necessary to use few loops in the loop, with a large section of the conductor and a high magnetic permeability core to increase the effective area. I also intend to minimize the tensions in the resonant circuit, there are partners who can suffer electrocution risk, since the equipment works at one hundred percent humidity and other times submerged.
So far I have changed the cores of the air antennas for ferrites, and now I would like to use mu-metal that has very high magnetic permeability. I see hard to get that material. I have seen that they manufacture rods of several cm in diameter. It would be interesting to contact the manufacturer and ask for samples, if someone sees it feasible to say something about it.
I have always worked in the near field for the use of radiolocation, and speaking with Luis EA5DOM, we discussed the effectiveness of using the electric field or the magnetic field with air, knowing that it is the magnetic that crosses the rocky pack more easily . I appreciate the comments on this part by this group.

Regards
Juan Leandro


El 3 feb. 2018 21:35, "Jacek Lipkowski" <sq5bpf@lipkowski.org> escribió:
On Sat, 3 Feb 2018, VIGILANT Luis Fernández wrote:

Jacek, you mentioned what I was midnight oiling here
" If you want some semi-DX in the H-field, then try coupling into some long
conductors (pipes, power lines, railway tracks etc)"

And i forgot phone lines :)

Actually there has been a 700m phone line, that was well grounded at the phone exchange (old exchange, no local modules were used, so the wire went all the way there). This makes a nice ground dipole when a transmitter is placed between the local ground and the grounded wire from the phone line. Putting abt.  30mA at 8.97kHz (this was when 9kHz was the ITU limit) gave a very nice signal 600-700m from the phone line.


What about coupling the loop to my 90m vertical ?
Adding another transformer from loop to vertical or just winding some coils of the vertical over the
small loop ring would work ?

No, because the amount of current induced in the mast would be very small.

BTW i wish i had a 90m vertical.


VY 73

Jacek / SQ5BPF

--------------090600000708000608030000--