Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-dc05.r1000.mx.aol.com (Internet Inbound) with ESMTP id 7E1FE38000432; Tue, 30 Aug 2011 07:55:43 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1QyMuC-0004kf-Mb for rs_out_1@blacksheep.org; Tue, 30 Aug 2011 12:55:00 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1QyMuC-0004kW-57 for rsgb_lf_group@blacksheep.org; Tue, 30 Aug 2011 12:55:00 +0100 Received: from nm8.bullet.mail.sp2.yahoo.com ([98.139.91.78]) by relay1.thorcom.net with smtp (Exim 4.63) (envelope-from ) id 1QyMuB-0002XJ-7g for rsgb_lf_group@blacksheep.org; Tue, 30 Aug 2011 12:55:00 +0100 Received: from [98.139.91.67] by nm8.bullet.mail.sp2.yahoo.com with NNFMP; 30 Aug 2011 11:54:52 -0000 Received: from [98.139.91.17] by tm7.bullet.mail.sp2.yahoo.com with NNFMP; 30 Aug 2011 11:54:52 -0000 Received: from [127.0.0.1] by omp1017.mail.sp2.yahoo.com with NNFMP; 30 Aug 2011 11:54:52 -0000 X-Yahoo-Newman-Property: ymail-3 X-Yahoo-Newman-Id: 50609.60859.bm@omp1017.mail.sp2.yahoo.com Received: (qmail 97334 invoked by uid 60001); 30 Aug 2011 11:54:51 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yahoo.com; s=s1024; t=1314705291; bh=ZK/JtxB4DTZw5AnxAMo052ULI9gfMTs34ZkRjP7b14c=; h=X-YMail-OSG:Received:X-Mailer:References:Message-ID:Date:From:Reply-To:Subject:To:MIME-Version:Content-Type; b=EQ22wxWO/ecHlMLN7u6e2FGwglWWNQETe4vRjEpe01X98eTGaaP3XO992gvHunhzYGxLIsxjXV8ymtEU+CDZpfCp0tG8DprhLcphpdU1IJQvVyuMfP572VNyNwl91ePLVuqD2mZlPB4n0Mpykx9RaUyHvNmCSOJq2oqni5Omcao= DomainKey-Signature:a=rsa-sha1; q=dns; c=nofws; s=s1024; d=yahoo.com; h=X-YMail-OSG:Received:X-Mailer:References:Message-ID:Date:From:Reply-To:Subject:To:MIME-Version:Content-Type; b=HK7vSgXS4GTlOHiFlDbLpytzY9dmdOddzGlqX7lUX4L63H4Jh+v+nJqEI9BRGTiUs6AJIwmZk9kSD5jDzBhCZBujkx5mEL476oJeVBcqs8Z5TmhvJD7fbInNslG9TaGL+0noSnMp0yT49lwM8Q8NN+R+QZRqKkOLcgO8rF7k8Fc=; X-YMail-OSG: ul1vQO4VM1lWLwOKf7VV8d30g09tWoRnoK.M1Zd75LzSH6b DvP8UYJfpUCCtT2Kk7_Tohz19zS4AGE7WNjcI1i.VD9vz1ltUD7HjkeSzpxn v3uLjrEJnyHc63JbuVXdkl7l5jCZTrgHd0wq2ECaEZZkJUplS2dsGGxg8dD5 s9XYOMk5dNYvro3NlHNT2d04cl9yGV_kk9.CvfMP10.QKap7N8evUDyvBP58 Oc7d77AcxI12LYIDkkdg34fP1eOj.ihvgPX4jN1hIpjCRiRRnI2bGZDkfNpM c4PmUzt5URzR3auWFOrSH8p8TkadxuFErSsPdi8JsiHQLxRDDet4rtR3qNi2 C46OtYsMRUOPSoiZyGTRb175cbpM7g2RsPS33dd3vp2sF6YkTYg8LYbzzpcy y1XUH3mDYCIKbwXcGvhmihRn5 Received: from [151.99.187.181] by web111920.mail.gq1.yahoo.com via HTTP; Tue, 30 Aug 2011 04:54:51 PDT X-Mailer: YahooMailWebService/0.8.113.315625 References: <16BC8B3CA8672445BC2A29B4C14A26D4379ED2AAB4@exlnmb01.eur.nsroot.net> <4DF9EFD1.5010208@iup.uni-heidelberg.de> <1313780109.51443.YahooMailNeo@web111907.mail.gq1.yahoo.com> <9CD1E11E8BC9402CB4AECECAC4088443@JimPC> <1314394178.5030.YahooMailNeo@web111905.mail.gq1.yahoo.com> <1314641183.5605.YahooMailNeo@web111910.mail.gq1.yahoo.com> <4E5CBC9A.5020900@iup.uni-heidelberg.de> Message-ID: <1314705291.83832.YahooMailNeo@web111920.mail.gq1.yahoo.com> Date: Tue, 30 Aug 2011 04:54:51 -0700 (PDT) From: Daniele Tincani To: "rsgb_lf_group@blacksheep.org" MIME-Version: 1.0 DomainKey-Status: good (testing) X-Spam-Score: 1.4 (+) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001,HTML_TINY_FONT=1.425 Subject: Re: LF: Re: Ferrite wideband antennas? Content-Type: multipart/alternative; boundary="0-1652941889-1314705291=:83832" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=1.0 required=5.0 tests=FORGED_YAHOO_RCVD,HTML_40_50, HTML_MESSAGE,TO_ADDRESS_EQ_REAL 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 x-aol-global-disposition: G X-AOL-SCOLL-SCORE: 0:2:462421024:93952408 X-AOL-SCOLL-URL_COUNT: 0 X-AOL-SCOLL-AUTHENTICATION: mail_rly_antispam_dkim-m204.1 ; domain : yahoo.com DKIM : fail x-aol-sid: 3039ac1d40854e5ccfbf054e X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none --0-1652941889-1314705291=:83832 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable =A0=0AHello Stefan,=0A=A0=0AThanks a lot for your feedback.=0A=A0=0AYesterd= ay evening a purchased a bunch of 7 x MU400HH ferrites (10mm x 200mm each) = on eBay, planning to join them together "in parallel" to form a fatter rod,= no idea if it will be a good choice but let's play with this new toy ;-) M= eanwhile I'm collecting ideas and hints from the web about construction (sh= ielding, computing/measuring parameters, ect.). Projects are stacking as us= ual :-)=0A=A0=0ABest regards=0ADaniele=0A=A0=0A=0AFrom: Stefan Sch=E4fer =0ATo: rsgb_lf_group@blacksheep.org=0A= Sent: Tuesday, August 30, 2011 12:34 PM=0ASubject: Re: LF: Re: Ferrite wide= band antennas?=0A=0A=0AHi Daniele,=0A=0A=0ACould it be possible to tune a f= errite loop over a frequency range as wide as 100-500KHz? Or at least over = the EU NDB band (say 300-500KHz)?=0A>Any practical suggestion (and/or refer= ences on the web) about how to build it?I think it is no problem. A narrow = band but adjustable antenna is a good choice. Just use a large variable cap= , e.g. 2x500 pF. It may be helpful to use switched caps and a smaller varia= ble cap like i did. If you have a high Q antenna, you can then easily fine = tune the system.=0ASo maybe 5...100 pF +100 pF+180 pf+270 pF+560 pF or so, = depending on your L.=0A=0AAbout the ferrites, there are several sellers on = eBay who offer a russian MU400HH type. Would it be suitable for LF?Yes, ver= y suitable. I have exactly these types in my LF ferrite antenna and got a Q= of 480. Q will change over the frequency. So maybe it is even helpful to r= ealise a switched L, for the higher frequencies.=0A=0A73, Stefan --0-1652941889-1314705291=:83832 Content-Type: text/html; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable
 
Hello Stefan,
 
Thanks a lot for= your feedback.
 
Yesterday evening a purchased a bunch of 7 x = MU400HH ferrites (10mm x 200mm each) on eBay, planning to join them togethe= r "in parallel" to form a fatter rod, no idea if it will be a good choice b= ut let's play with this new toy ;-) Meanwhile I'm collecting ideas and hint= s from the web about construction (shielding, computing/measuring parameter= s, ect.). Projects are stacking as usual :-)
 
Best regards
Daniele
 

From: Stef= an Sch=E4fer <Stefan.Schaefer@iup.uni-heidelberg.de>
To: rsgb_lf_group@blacksheep.org
<= SPAN style=3D"FONT-WEIGHT: bold">Sent: Tuesday, August 30, 2011 = 12:34 PM
Subject: Re: LF= : Re: Ferrite wideband antennas?

Hi Daniele,

Could it be possible to tune a ferrite loop over a frequency ran= ge as wide as 100-500KHz? Or at least over the EU NDB band (say 300-500KHz)= ?
Any practical suggestion (and/or references on the web) about ho= w to build it?
I think it is no probl= em. A narrow band but adjustable antenna is a good choice. Just use a large= variable cap, e.g. 2x500 pF. It may be helpful to use switched caps and a = smaller variable cap like i did. If you have a high Q antenna, you can then= easily fine tune the system.
So maybe 5...100 pF +100 pF+180 pf+270 pF+= 560 pF or so, depending on your L.
About the ferrites, there are several sellers on eBay who offer = a russian MU400HH type. Would it be suitable for LF?
Yes, very suitable. I have exactly these types in my LF fer= rite antenna and got a Q of 480. Q will change over the frequency. So maybe= it is even helpful to realise a switched L, for the higher frequencies.
73, Stefan


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