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 w16BqkLO018738 for ; Tue, 6 Feb 2018 12:52:47 +0100 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1ej1if-0007Jk-Ib for rs_out_1@blacksheep.org; Tue, 06 Feb 2018 11:47:25 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1ej1ie-0007Jb-RF for rsgb_lf_group@blacksheep.org; Tue, 06 Feb 2018 11:47:24 +0000 Received: from mail-pg0-x235.google.com ([2607:f8b0:400e:c05::235]) by relay1.thorcom.net with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.89) (envelope-from ) id 1ej1iZ-0005cm-E9 for rsgb_lf_group@blacksheep.org; Tue, 06 Feb 2018 11:47:23 +0000 Received: by mail-pg0-x235.google.com with SMTP id g2so980940pgn.7 for ; Tue, 06 Feb 2018 03:47:19 -0800 (PST) X-DKIM-Result: Domain=gmail.com Result=Good and Known Domain DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:in-reply-to:references:from:date:message-id:subject:to; bh=xxWdbGoMMBpZG56nLEJ0hxmp7FaAKB4NqKcJ11O3i3Y=; b=jtYGUBFMJd3hJGpr+ws6JjPQOc004O4uNXYwyur/uodjFF+0RoHo4d4q4N08XXU55Z VpPjEMGFMr5zVg8Q5g1j2vhdPfh3bp0YOIKbytAXHBInw1V0ISnWCCTywoUi298R1PHp yU4S9HcUyiEXqFwj3fo2MlqcwxhR6TiN9M6xdGiW/mZuN21Foc0bAKWGN7g8BIS+9qmW RQj0vGExihwmrPnED4o/TZ4a+xRF5g2egMlxbUoW86GQYMFkK6AqT5dDYVbqHqD3U/vQ 5ph4xEgXM6P1JRqZirhU57R+Rnvo8y0+zlxWjx7yM/mg5GARDm5Zdpbi9VAyhv+ZzNV0 zD3Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to; bh=xxWdbGoMMBpZG56nLEJ0hxmp7FaAKB4NqKcJ11O3i3Y=; b=PQh3EertZMVtNW0pC7VJL3Yxb1Z26+QIvLeycu/KDIyeBNQS953DmBHC9gRU5yc4KE D9CNsVdtQkdg3aU58gokMw2rPh/EsZQWxqyK08WjjmmH5kc5mTyxW/qJxPLCh2WDbK2M rIssEKxntQKAhYnS/RCTeyP+1JfsAy92AIwioM8VDk3T/E/U4vhZtk6+IU+ub177uxnt WKg3s8Orima0JxNIpoUCC8YwWCAtbhr+ofT+rEWP8F9LrWR+XkKxBqAk0UhCBw4oMEEf xKOuDuh5S/Nq9gWwSKxJPOV8sOSNac9fCg8NTRHyY5/dpa0zoI+Q9sZ70hKXRdGEWytH 9Ttg== X-Gm-Message-State: APf1xPCdFV5O/yRNLJ4F8TahdpOAGpTMe3JteXhCeQyMrMIGDbSMMLY8 U+2qUoJnEJbWb6dtN5SsrSyJUMP/4VshuNBPMaw= X-Google-Smtp-Source: AH8x226EvCUqhJdorNnS8wlWtoHmNP9BuY0xlav2WKOpWc4NhSakikZbxnd8vR0s6asZc40HYHKJALvBylWulomQLFw= X-Received: by 10.98.93.144 with SMTP id n16mr2179893pfj.195.1517917636531; Tue, 06 Feb 2018 03:47:16 -0800 (PST) MIME-Version: 1.0 Received: by 10.100.224.137 with HTTP; Tue, 6 Feb 2018 03:47:15 -0800 (PST) Received: by 10.100.224.137 with HTTP; Tue, 6 Feb 2018 03:47:15 -0800 (PST) In-Reply-To: <579355A36AEE9D4FA555C45D556003AB9AB4AE5D@servigilant.vigilant.local> 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> <5A78B653.7050401@posteo.de> <579355A36AEE9D4FA555C45D556003AB9AB4AE5D@servigilant.vigilant.local> From: Juan Leandro Ronda Date: Tue, 6 Feb 2018 12:47:15 +0100 Message-ID: To: rsgb_lf_group@blacksheep.org 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 Stefan, I do not have nearby caves around my house to do continuous tests. The new receiver, Winter, is ready to be inserted into a cavity and I want to make comparative observations between the inside and the outside. It will be published in the CREG JOURNAL of the BCRA at the beginning of March. I want to prepare a loop without tuning and in SL observe feedback, if it is relevant I will do tests inside the cavity. The reception tests from magnetic antenna to electric antenna was only out of curiosity, it is not the desired end. The teams are prototypes in continuous evolution, although they come using punctually to radiolocalize some point of the cavity. It is easy for us to lower frequency in the following developments, lower than 5000Hz. I have started to use radio using the magnetic field and I really want to experiment with the electric field. [...] Content analysis details: (0.0 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (juanleronda[at]gmail.com) 0.0 T_KAM_HTML_FONT_INVALID BODY: Test for Invalidly Named or Formatted Colors in HTML 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: bf844c50f354270eff55c61daa0e15fb Subject: RE: LF: VLF Small magnetic antenna for Tx Content-Type: multipart/alternative; boundary="001a113cfd5e861a92056489bd6a" 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_20_30,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 --001a113cfd5e861a92056489bd6a Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Hi Stefan, I do not have nearby caves around my house to do continuous tests. The new receiver, Winter, is ready to be inserted into a cavity and I want to make comparative observations between the inside and the outside. It will be published in the CREG JOURNAL of the BCRA at the beginning of March. I want to prepare a loop without tuning and in SL observe feedback, if it is relevant I will do tests inside the cavity. The reception tests from magnetic antenna to electric antenna was only out of curiosity, it is not the desired end. The teams are prototypes in continuous evolution, although they come using punctually to radiolocalize some point of the cavity. It is easy for us to lower frequency in the following developments, lower than 5000Hz. I have started to use radio using the magnetic field and I really want to experiment with the electric field. Regards Juan Leandro El 6 feb. 2018 11:45 a. m., "VIGILANT Luis Fern=C3=A1ndez" escribi=C3=B3: > Hi Stefan, VLF > > > > Appart from CB license. Ref your other questions there are other group of > Hams and also Cave explorers in Galicia. They have made very interesting > > test of RX inside the cavity. Last test was this Christmast and they coul= d > clearly copy LF broadcast stations at noon. The distance from sourface to > > the cavity site was about 50m with an small and complex pass. The 11904Hz > Alpha was also detected with an E-probe to souncard. But the most > > amazing recepcion was in FM band at 98.7MHz receiving =E2=80=9CRadio Clas= ica=E2=80=9D > perfectly loud > > > > Thanks to Javier EB1HBK, this is the link to the video. Hearing Maria > Calas in La Bohemme down in the cave is something =E2=80=9Cunique=E2=80= =9D. Enjoy J > > https://www.dropbox.com/s/augytnbx24nanjp/VID_20171224_141907.3gp?dl=3D0 > > > > Ham signals in 40m weare also very strong using a loop antenna. The EA7FC= , > EA7SJ stations which can be heard in this video were almost 800Km away > > https://www.dropbox.com/s/b92dmyfqqc4inh8/VID_20171224_154455.3gp?dl=3D0 > > > > They are prepairing a new test. The idea is to record spectrum but in > surface and in cavity at the same time. May be the best way is to do it > > with SL recording 24 or 48KHz wide CB band > > > > Can you prepare a .usr file to config SpecLab to do it? So they will be > able to share the files in the reflector for further analisys > > > > 73 de Luis > > EA5DOM > > > > *De:* owner-rsgb_lf_group@blacksheep.org [mailto:owner-rsgb_lf_group@ > blacksheep.org] *En nombre de *DK7FC > *Enviado el:* lunes, 05 de febrero de 2018 20:54 > *Para:* rsgb_lf_group@blacksheep.org > *Asunto:* Re: LF: VLF Small magnetic antenna for Tx > > > > 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 sam= e > 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 reaso= n > 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 incredib= le > the behavior before the great tension and amperage, they have the > disadvantage of having limit of high values =E2=80=8B=E2=80=8Bof 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" escribi=C3=B3: > > 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 give= s > a magnetic moment of 100A per square meter. I verify that in the center o= f > 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 coil= s > of the TV deflection coils and I observed good operation, I also circulat= ed > 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 n=C2=BA99 " 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 necessar= y > 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 partne= rs > who can suffer electrocution risk, since the equipment works at one hundr= ed > 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 manufactur= er > and ask for samples, if someone sees it feasible to say something about i= t. > > 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=3D1V4K2T2e3ActVqPaHr1xXLcjBkD16NtG= B > > > > > > Regards > > Juan Leandro > > > > El 4 feb. 2018 8:35 p. m., "Juan Leandro Ronda" > escribi=C3=B3: > > 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 give= s > a magnetic moment of 100A per square meter. I verify that in the center o= f > 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 coil= s > of the TV deflection coils and I observed good operation, I also circulat= ed > 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 n=C2=BA99 " 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 necessar= y > 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 partne= rs > who can suffer electrocution risk, since the equipment works at one hundr= ed > 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 manufactur= er > and ask for samples, if someone sees it feasible to say something about i= t. > > 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" escribi=C3= =B3: > > On Sat, 3 Feb 2018, VIGILANT Luis Fern=C3=A1ndez 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 lo= ng > 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 wen= t > 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 > > > > --001a113cfd5e861a92056489bd6a Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Hi Stefan,=C2=A0

=C2=A0 =C2=A0I do not have nearby caves around my house to do continuo= us tests. The new receiver, Winter, is ready to be inserted into a cavity a= nd I want to make comparative observations between the inside and the outsi= de. It will be published in the CREG JOURNAL of the BCRA at the beginning o= f March. I want to prepare a loop without tuning and in SL observe feedback= , if it is relevant I will do tests inside the cavity. The reception tests = from magnetic antenna to electric antenna was only out of curiosity, it is = not the desired end. The teams are prototypes in continuous evolution, alth= ough they come using punctually to radiolocalize some point of the cavity. = It is easy for us to lower frequency in the following developments, lower t= han 5000Hz. I have started to use radio using the magnetic field and I real= ly want to experiment with the electric field.

<= /div>
Regards
Juan Leandro

El 6 feb. 2018= 11:45 a. m., "VIGILANT Luis Fern=C3=A1ndez" <luis@vigilant.es> escribi=C3=B3:

Hi Stefan, VLF

=C2=A0

Appart from CB license. Ref your other questions there are oth= er group of Hams and also Cave explorers in Galicia. They have made very in= teresting

test of RX inside the = cavity. Last test was this Christmast and they could clearly copy LF broadc= ast stations at noon. The distance from sourface to

the cavity site was ab= out 50m with an small and complex pass. The 11904Hz Alpha was also detected= with an E-probe to souncard. But the most

amazing recepcion was = in FM band at 98.7MHz receiving =E2=80=9CRadio Clasica=E2=80=9D perfectly l= oud

=C2=A0

Thanks to Javier EB1HB= K, this is the link to the video. Hearing Maria Calas in La Bohemme down in= the cave is something =E2=80=9Cunique=E2=80=9D. Enjoy J

https://www.dropbox.com/s/augytnbx24nanjp/VID_20171224_1419= 07.3gp?dl=3D0

=C2=A0

Ham signals in 40m wea= re also very strong using a loop antenna. The EA7FC, EA7SJ stations which c= an be heard in this video were almost 800Km away

https://www.dropbox.com/s/b92dmyfqqc4inh8/VID_20171224_1544= 55.3gp?dl=3D0

=C2=A0

They are prepairing a = new test. The idea is to record spectrum but in surface and in cavity at th= e same time. May be the best way is to do it

with SL recording =C2= =A024 or 48KHz wide CB band

=C2=A0

Can you prepare a .usr= file to config SpecLab to do it? So they will be able to share the files i= n the reflector for further analisys =C2=A0

=C2=A0

73 de Luis

EA5DOM

=C2=A0

De: o= wner-rsgb_lf_group@blacksheep.org [mailto:owner-rsgb_lf_group@bl= acksheep.org] En nombre de DK7FC
Enviado el: lunes, 05 de febrero de 2018 20:54
Para: rsgb_lf_group@blacksheep.org
Asunto: Re: LF: VLF Small magnetic antenna for Tx

=C2=A0

Hi Juan,

Good luck with your tests. Do you have/need a special license for transmitt= ing on that frequency or is it free for everyone unless you stay below a ce= rtain 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 un= der ground. A non-resonated loop.
Right now i am transmitting on 970 Hz. That frequency will pass the soil an= d 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 intere= sting :-)

73, Stefan

Am 05.02.2018 20:30, schrieb Juan Leandro Ronda:

Hi Stefan,=C2=A0

=C2=A0 =C2=A0=C2=A0

=C2=A0 =C2=A0A 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 ob= served 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 =E2=80=8B=E2=80=8Bof = capacity. I want to perform a test with Luis orienting the loop to his ante= nna, we are 49 km away, but he always has a lot of noise at 38KHz.

=C2=A0

Regards

Juan Leandro

=C2=A0

El 5 feb. 2018 19:33, "DK7FC" <selberdenken@posteo.de= > escribi=C3=B3:

Interesting.
I built a similar loop and transmitted on MF. The maximum power was about 3= 0 W RF because the resonating Cs (WIMA-FKP-1, 2kV) became warm and the reso= nance drifted away. But i managed up to 450 km distance with that compact a= ntenna.

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:

=C2=A0 =C2=A0 I have to say that I am also lacking in = theory, but the tests carried out on airborne and core coils have been succ= essful and are working.

The most relevant loop antenna has been an octagon-sha= ped 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 sq= uare meter. I verify that in the center of the octagon I am condensing enou= gh the magnetic flux, knowing that it is very difficult to saturate the air. In summer I get to notice heatin= g 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 obs= erved good operation, I also circulated a large amperage for it, giving ris= e to the development of a new transmitter for radiolocation, it is the Summ= er, published in the CREG JOURNAL n=C2=BA99 " of the BCRA.

I have always wanted to use the power through low volt= age 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 cor= e 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 fo= r ferrites, and now I would like to use mu-metal that has very high magneti= c 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 effectivenes= s of using the electric field or the magnetic field with air, knowing that it is the magnetic that crosses the rocky pac= k more easily . I appreciate the comments on this part by this group.

=C2=A0

=C2=A0

=C2=A0

Regards

Juan Leandro

=C2=A0

El 4 feb. 2018 8:35 p. m., "Juan Leandro Ronda&= quot; <juanle= ronda@gmail.com> escribi=C3=B3:

=C2=A0 =C2=A0 I have to say that I am also lacking i= n theory, but the tests carried out on airborne and core coils have been su= ccessful and are working.

The most relevant loop antenna has been an octagon-s= haped loop, formed by 22mm diameter copper pipe of 1mm thickness, equivalen= t to 66mm square, forming a surface of 1m square. As seen in the attached d= iagram, I put in resonance by LC series (38400Hz) giving close to 100A, which in turn gives a magnetic moment of 1= 00A per square meter. I verify that in the center of the octagon I am conde= nsing enough the magnetic flux, knowing that it is very difficult to satura= te 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 d= iverts the antenna's resonance.

Then I was forced to reduce the volume of the antenn= a for comfortable use in underground cavities. I had to resort to using cor= es to keep an effective area as large as possible. I tried what I had at ha= nd, the coils of the TV deflection coils and I observed good operation, I also circulated a large amperage fo= r it, giving rise to the development of a new transmitter for radiolocation= , it is the Summer, published in the CREG JOURNAL n=C2=BA99 " of the B= CRA.

I have always wanted to use the power through low vo= ltage and a lot of amperage, which will translate into great magnetic momen= t. It is necessary to use few loops in the loop, with a large section of th= e conductor and a high magnetic permeability core to increase the effective area. I also intend to minimize the tension= s in the resonant circuit, there are partners who can suffer electrocution = risk, since the equipment works at one hundred percent humidity and other t= imes 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 magne= tic permeability. I see hard to get that material. I have seen that they ma= nufacture rods of several cm in diameter. It would be interesting to contact the manufacturer and ask for samples, i= f someone sees it feasible to say something about it.

I have always worked in the near field for the use o= f radiolocation, and speaking with Luis EA5DOM, we discussed the effectiven= ess of using the electric field or the magnetic field with air, knowing tha= t it is the magnetic that crosses the rocky pack more easily . I appreciate the comments on this part by thi= s group.

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Regards

Juan Leandro

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El 3 feb. 2018 21:35, "Jacek Lipkowski" &l= t;sq5bpf@lipkowsk= i.org> escribi=C3=B3:

On Sat, 3 Feb 2018, V= IGILANT Luis Fern=C3=A1ndez 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)"

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And i forgot phone lines :)

Actually there has been a 700m phone line, that was well grounded at the ph= one exchange (old exchange, no local modules were used, so the wire went al= l the way there). This makes a nice ground dipole when a transmitter is pla= ced between the local ground and the grounded wire from the phone line. Putting abt.=C2=A0 30mA at 8.97kHz = (this was when 9kHz was the ITU limit) gave a very nice signal 600-700m fro= m the phone line.

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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 ?

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No, because the amount of current induced in the mas= t would be very small.

BTW i wish i had a 90m vertical.



VY 73

Jacek / SQ5BPF

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