Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-da04.r1000.mx.aol.com (Internet Inbound) with ESMTP id 21D19380000DC; Tue, 27 Sep 2011 11:17:38 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1R8ZNx-000414-Sp for rs_out_1@blacksheep.org; Tue, 27 Sep 2011 16:15:53 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1R8ZNx-00040v-5e for rsgb_lf_group@blacksheep.org; Tue, 27 Sep 2011 16:15:53 +0100 Received: from nm25-vm6.bullet.mail.ird.yahoo.com ([212.82.109.207]) by relay1.thorcom.net with smtp (Exim 4.63) (envelope-from ) id 1R8ZNw-0005a0-Ed for rsgb_lf_group@blacksheep.org; Tue, 27 Sep 2011 16:15:53 +0100 Received: from [77.238.189.48] by nm25.bullet.mail.ird.yahoo.com with NNFMP; 27 Sep 2011 15:15:46 -0000 Received: from [212.82.108.254] by tm1.bullet.mail.ird.yahoo.com with NNFMP; 27 Sep 2011 15:15:46 -0000 Received: from [127.0.0.1] by omp1019.mail.ird.yahoo.com with NNFMP; 27 Sep 2011 15:15:46 -0000 X-Yahoo-Newman-Property: ymail-3 X-Yahoo-Newman-Id: 343386.71598.bm@omp1019.mail.ird.yahoo.com Received: (qmail 3257 invoked by uid 60001); 27 Sep 2011 15:15:46 -0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=yahoo.com; s=s1024; t=1317136546; bh=UxNr+PL9Z+r5BveJVfUQ0/12ILMEVkqbPC5TbgDQi6o=; h=X-YMail-OSG:Received:X-Mailer:References:Message-ID:Date:From:Reply-To:Subject:To:MIME-Version:Content-Type; b=nif4qlI0D50ZcUKAmdqzDS9aqAedKmZ1h4zMvSpf9bpWPRnSN2TmNbPMUg+tK2vZM7/8J8I/MfkKS16OPM52LTrcwn85GEVUmUywMDtmR8nUx8V5cM/EcUvd58exWGvmCpHzfuPP2OXUXfj9ScxCk+0Q5ANCo2k3ESYicwr5ZJU= 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=jM9SsGwsAbz2O5pWqozRna0jv1dC16cr3iSkboWBM1N1OcEatnidlV/ILXFWoRinNaJkaKu/Fb2Vuel5dhlWaKELAp/QXu+Z3zX0eoPB/PnxNrfRhq8g34Ktk4bx2FxxnJhnOzDLEBqKCFGm00uz5R++CkvLtKQeMudrqV4GyrE=; X-YMail-OSG: td6sDD0VM1m0mSrJ72QmQ_QjXTK1wfFuhRtKj7tkGH8Qm_Y 47I6ke91UO9QsMZWcm4KZcdX8Wb53tgbMsje.malH7qtsMeYd31wxoCyuIYW MSWhf6z7mafql0e38jq5SRtHo6CytcB1qO5UZp9g.eo9ygv7jKo31pkbskJr rjIcwnqVUujPUOe3ToCYsh.UOEY0b0MPFENdMRlNvDuVKwgNWIPtENXnAfzY RB.qSJwKw1YFiDOYB2yA_4aRJpYq3R1EnP_T0ue7Rc8GMYcJDLskBvUabKVR 1dedtV6Kfk_1Ixvmf1LjLEK72ybKxCI6ISWIdNf9uVNxvZNIJgFXhGHYLRta XBcNL64ZUmNOEs7mTkT3rh6jI.0EnCjqomSrwh_mQIJWDhMyz2tVPd76S Received: from [151.99.187.181] by web29513.mail.ird.yahoo.com via HTTP; Tue, 27 Sep 2011 16:15:45 BST X-Mailer: YahooMailWebService/0.8.114.317681 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> <1314705226.37125.YahooMailNeo@web111901.mail.gq1.yahoo.com> <4E5CF192.3040905@legal-medicine.de> <1317076720.22768.YahooMailNeo@web29509.mail.ird.yahoo.com> <1317077173.13177.YahooMailNeo@web29509.mail.ird.yahoo.com> <1317119515.35504.YahooMailNeo@web29502.mail.ird.yahoo.com> <1317119586.50531.YahooMailNeo@web29505.mail.ird.yahoo.com> <4E81B80E.3030201@iup.uni-heidelberg.de> Message-ID: <1317136545.77621.YahooMailNeo@web29513.mail.ird.yahoo.com> Date: Tue, 27 Sep 2011 16:15:45 +0100 (BST) 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: My first ferrite experiments Content-Type: multipart/alternative; boundary="2133552103-2130413111-1317136545=:77621" 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: 0:2:445564992:93952408 X-AOL-SCOLL-URL_COUNT: 0 X-AOL-SCOLL-AUTHENTICATION: mail_rly_antispam_dkim-d023.1 ; domain : yahoo.com DKIM : fail x-aol-sid: 3039ac1d404c4e81e9124205 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none --2133552103-2130413111-1317136545=:77621 Content-Type: text/plain; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable Hello Stefan,=0A=A0=0A> but maybe the Q is reduced by the aluminium shield!= =0ADo you think the aluminium could be the problem or the distance between= the coil and the core? I could replace the aluminium tube with a plastic t= ube, if shielding is not necessary, but this would not improve the Q if the= problem is the gap between the coil and the core.=0A=A0=0A> Are the rods g= alvanically separated from each other by a thin plastic tape? What type is = the ferrite material?=0AYes I put two layers of plastic tape on tips of eac= h rod. The ferrite material is russian MU400HH.=0A=A0=0ABest regards=0ADani= ele=0A=A0=0A=0ADa: Stefan Sch=E4fer = =0AA: rsgb_lf_group@blacksheep.org=0AInviato: Marted=EC 27 Settembre 2011 1= 3:48=0AOggetto: Re: LF: Re: My first ferrite experiments=0A=0A=0AHello Dani= ele, =0A=0ANice work and good equipment.=0AI would suggest to make the wire= s between coil and cap as short as possible and not to use these crocodile = clamps. HF litz wire should help about the Q but maybe the Q is reduced by = the aluminium shield! Are the rods galvanically separated from each other b= y a thin plastic tape? What type is the ferrite material? =0A=0A73, Stefan/= DK7FC=0A=0APS: Tell me if you need a test signal ;-)=0A=0AAm 27.09.2011 12:= 33, schrieb Daniele Tincani: =0APics 3 and 4 are attached here.=0A>=A0=0A>= =0A>=0A>Da: Daniele Tincani =0A>A: "rsgb_lf_group= @blacksheep.org" =0A>Inviato: Marted=EC 27 Se= ttembre 2011 12:31=0A>Oggetto: My first ferrite experiments=0A>=0A>=0A>=0A>= =0A>Hello LF,=0A>=0A>=0A>this evening I had some free time to spend for sta= rting my very simple tests with ferrite rods. Picture 1 in the attached zip= file shows one of the rods (about 10mm diameter x 200mm long) together wit= h a short piece of plastic tube that I have used to adapt the rods to a lar= ger-diameter slotted aluminium tube -=A0shown in picture 2. As you can see,= the longitudinal cut on the tube is not really regular and "clean". I'm no= t very good at working with metals. Nevertheless, I hope it will do the job= , that is acting as a shield between the rods and the coil. Picture=A03 sho= ws two of the three rods I used, each inserted=A0in a short piece of plasti= c pipe and protected with heat shrink tube and some masking tape.=0A>Finall= y, picture=A04 shows the=A0very provisional setup that I used to try measur= ing Q of an LC pair composed by a 2-gangs variable capacitor plus a 55-turn= s coil wound over the aluminium tube containing the ferrite rods. I perform= ed several measures, with 1, 2 or 3 rods inside the tube. I saw that using = 3 rods increases the inductance significantly. For example,=A0at an interme= diate position of the varcap, resonance was at 1037KHz with only 1 rod insi= de the tube, but it was at 767 KHz with 3 rods.The=A0Q value also increases= slightly using 3 rods, even thought in my tests I got only=A0a miserable f= igure of about 30. Anyway, I=A0 decided to go with 3 rods for my next step,= that will be to try Litz wire for the coil and see what happens.=0A>=0A>No= te: pics 3 and 4 will be attached to a re-sent of this message.=0A>=0A>Rega= rds=0A>D.=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A>=0A> --2133552103-2130413111-1317136545=:77621 Content-Type: text/html; charset=iso-8859-1 Content-Transfer-Encoding: quoted-printable
<= SPAN id=3Dyiv1453326460yui_3_2_0_14_131713566775057 style=3D"RIGHT: auto">H= ello Stefan,
 
> but maybe the Q is reduced by the alum= inium shield!
Do you think the= aluminium could be the problem or the distance between the coil and the co= re? I could replace the aluminium tube with a plastic tube, if shielding is= not necessary, but this would not improve the Q if the problem is the gap = between the coil and the core.
 
> Are the rods galvanically separated = from each other by a thin plastic tape? What type is the ferrite material?<= /SPAN>
Yes I put two layers of plastic tape on tips o= f each rod. The ferrite material is russian MU400HH.
 
Best regards<= /DIV>
Daniele
 

Da: Stef= an Sch=E4fer <Stefan.Schaefer@iup.uni-heidelberg.de>
A: rsgb_lf_group@blacksheep.org
Inviato: Marted=EC 27 Settembre = 2011 13:48
Oggetto: Re: = LF: Re: My first ferrite experiments

Hello Daniele,

Nice w= ork and good equipment.
I would suggest to make the wires between coil a= nd cap as short as possible and not to use these crocodile clamps. HF litz = wire should help about the Q but maybe the Q is reduced by the aluminium sh= ield! Are the rods galvanically separated from each other by a thin plastic= tape? What type is the ferrite material?

73, Stefan/DK7FC

P= S: Tell me if you need a test signal ;-)

Am 27.09.2011 12:33, schrie= b Daniele Tincani:=20
Pics 3 and 4 are atta= ched here.
 

= Da: Daniele Tincani <danieletincani@yahoo.com>=
A: "rsgb_lf_group@blacksheep.org" <rsgb_lf_gro= up@blacksheep.org>
Inviato:<= /SPAN> Marted=EC 27 Settembre 2011 12:31
Oggetto: My first ferrite experiments

 
Hello LF,
 
this evening I had some free time to spend for starting my very simple= tests with ferrite rods. Picture 1 in the attached zip file shows one of t= he rods (about 10mm diameter x 200mm long) together with a short piece of p= lastic tube that I have used to adapt the rods to a larger-diameter slotted= aluminium tube - shown in picture 2. As you can see, the longitudinal= cut on the tube is not really regular and "clean". I'm not very good at wo= rking with metals. Nevertheless, I hope it will do the job, that is acting = as a shield between the rods and the coil. Picture 3 shows two of the = three rods I used, each inserted in a short piece of plastic pipe and = protected with heat shrink tube and some masking tape.
Finally, picture 4 shows the very provisional setup that I u= sed to try measuring Q of an LC pair composed by a 2-gangs variable capacit= or plus a 55-turns coil wound over the aluminium tube containing the ferrit= e rods. I performed several measures, with 1, 2 or 3 rods inside the tube. = I saw that using 3 rods increases the inductance significantly. For example= , at an intermediate position of the varcap, resonance was at 1037KHz = with only 1 rod inside the tube, but it was at 767 KHz with 3 rods.The = ;Q value also increases slightly using 3 rods, even thought in my tests I g= ot only a miserable figure of about 30. Anyway, I  decided to go = with 3 rods for my next step, that will be to try Litz wire for the coil and see what happens.
 
Note: pics 3 and 4 will be = attached to a re-sent of this message.
 
Regards
D.








=

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