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 w2BCudUE022126 for ; Sun, 11 Mar 2018 13:56:42 +0100 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1ev0Ig-00061w-5U for rs_out_1@blacksheep.org; Sun, 11 Mar 2018 12:42:06 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1ev0I8-00061n-G0 for rsgb_lf_group@blacksheep.org; Sun, 11 Mar 2018 12:41:32 +0000 Received: from mail-qt0-x230.google.com ([2607:f8b0:400d:c0d::230]) by relay1.thorcom.net with esmtps (TLSv1.2:ECDHE-RSA-AES256-GCM-SHA384:256) (Exim 4.89) (envelope-from ) id 1ev0I2-0007IO-KI for rsgb_lf_group@blacksheep.org; Sun, 11 Mar 2018 12:41:30 +0000 Received: by mail-qt0-x230.google.com with SMTP id a23so16061390qtn.0 for ; Sun, 11 Mar 2018 05:41:26 -0700 (PDT) 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=GjwnPe1hM+xXV8zXL9HjzdkGnhdjPWym/6cnBwzcNfo=; b=SsXK0l0ze67cexsSnX9yNNm3hHXIAC5dmyaPzPXz0iKhUyYLSm2kr8ggmBVolmySij t7KUT+GzeVUKkVMknxK2/LenkUE0Aqo94iw4EcnQEzWVKquV9IqF0Fsw9OzrD7Hj2S/y OM3Rj0bJcuKA2ocqUNVnTO+6FTpwdRO+GN1u4M0cNhaTLMKx4NRRnBKeF0iXGRCWud4g Mybii8yZ19o8M08VYptx6grwBbUxB+r3Nuv6U8NsCIVB+sltWAFXoAGx983BiqIbXJ0U fUXkQQT9HzfIPURnuNr3PaFLM8Hbt3AlkjTdGJPGvcT5HkuPVXlvQDe8moBEMTShPyO2 4ftQ== 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=GjwnPe1hM+xXV8zXL9HjzdkGnhdjPWym/6cnBwzcNfo=; b=uXVQ23Xu4lfzIyBd/G8OsrYhtyfpjdpfnMW50mWbzekVc49g6zRMqEfQJoV4ZWvrgb Cb3/i5vrRv395b737D/S7lBqW7wC4Sg93clGU2ltO4cN4T1esWPL1QyEoeZ5eT4TT8bT lRsflXR8ETb13qUW5ijeRHgE2J++ES0TDzGk8XxdwP6Ye8o2tVLu5+1QfAjan9ZHBC2+ 5zNp0y9iJHr2Kp7J2XVYUQ0RbY0pj5uKJXIVAoZbFYGz2xZy/zrVVNUaR64oWBTpYYr6 +AoyTPFBQ7aaODhI+HkFxCJ3yMN1xqQLp92gniu2Ze9DdAjGyoA5CooN8v4CKkNsKYpX Ys7w== X-Gm-Message-State: AElRT7GEX01nVLcPPytMkl0R4l9bOi+D5SZWwA81QdN0B2lrwFKxXHLo BFfzAu4IlhFs0ccPsl5iLlIZAgC8mxy7kVbZWbpaNQ== X-Google-Smtp-Source: AG47ELu2DN9przDBM7lrtY7oM6XiO0n1cV9azzdtnY5BgxrQr0JUjcIzP3Cr5Me9QljnDgvcptKvCRJlf5vSwfLNiSk= X-Received: by 10.200.55.37 with SMTP id o34mr7039974qtb.94.1520772083758; Sun, 11 Mar 2018 05:41:23 -0700 (PDT) MIME-Version: 1.0 Received: by 10.12.191.185 with HTTP; Sun, 11 Mar 2018 05:41:23 -0700 (PDT) In-Reply-To: <5C95AD9F393E467884DFB2F614EAB2BB@DELL4> References: <3610102492.20180308120003@gmail.com> <5C95AD9F393E467884DFB2F614EAB2BB@DELL4> From: David Bowman Date: Sun, 11 Mar 2018 12:41:23 +0000 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 Chris. I had that problem too. - See: http://www.g0mrf.com/decca.htm [...] 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 (davidg0mrf[at]gmail.com) 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: c40596c1cc3306f1877076595a921c57 Subject: Re: LF: Re: Can an air cored LPF inductor have as high a "Q" as a toroidal wound one? Content-Type: multipart/alternative; boundary="001a11398234d65677056722573e" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.6 required=5.0 tests=HTML_20_30, 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 --001a11398234d65677056722573e Content-Type: text/plain; charset="UTF-8" Hi Chris. I had that problem too. - See: http://www.g0mrf.com/decca.htm Eventually I had to remove a T225-3 in the low pass and replace it with 2 stacked (superglued) T200-2. That should work well at your power levels. 73 David G0MRF On Thu, Mar 8, 2018 at 1:15 PM, wrote: > Tested -3 material ... it has higher losses at LF. > > Jay W1VD > > > ----- Original Message ----- From: "Chris Wilson" > To: > Cc: > Sent: Thursday, March 08, 2018 7:00 AM > Subject: LF: Can an air cored LPF inductor have as high a "Q" as a > toroidal wound one? > > > >> >> Hello expert LF'ers! >> >> The centre toroid of my three toroid LPF heats up on the longer >> transmissions like WSPR15. I have added a small fan as a crutch >> (thanks N1BUG!) but I guess that's a crutch for inadequate hardware. I >> was wondering whether instead of buying a larger toroid, which seem >> only to be available from the US at high cost, I could wind an air >> cored coil of similar inductance. But I am unsure whether it would >> have the required "Q" factor. Your opinions please? Thanks, >> >> Also I am wondering, looking at the Micrometals site, whether the >> current -2 material can be bettered by using -3 material? >> >> http://www.w1vd.com/LPF.pdf >> >> and info on frequency range of these cores is at: http://toroids.info/ >> >> >> -- >> Best regards, >> Chris mailto:dead.fets@gmail.com >> >> >> > --001a11398234d65677056722573e Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Hi Chris.

I had that prob= lem too. - See:

http://ww= w.g0mrf.com/decca.htm

Eventually I had to remove a T225-3 = in the low pass and replace it with 2 stacked (superglued) T200-2.

<= /div>That should work well at your power levels.

73

Dav= id=C2=A0 G0MRF

On Thu, Mar 8, 2018 at 1:15 PM, <jrusgrove@comcast.net>= wrote:
Tested -3 material ... it = has higher losses at LF.

Jay W1VD


----- Original Message ----- From: "Chris Wilson" <dead.fets@gmail.com> To: <r= sgb_lf_group@blacksheep.org>
Cc: <dead.fets@= gmail.com>
Sent: Thursday, March 08, 2018 7:00 AM
Subject: LF: Can an air cored LPF inductor have as high a "Q" as = a toroidal wound one?




Hello=C2=A0 expert LF'ers!

The=C2=A0 centre=C2=A0 toroid=C2=A0 of=C2=A0 my=C2=A0 three=C2=A0 toroid=C2= =A0 LPF heats up on the longer
transmissions=C2=A0 like=C2=A0 WSPR15.=C2=A0 I=C2=A0 have=C2=A0 added=C2=A0= a=C2=A0 small fan as a crutch
(thanks=C2=A0 N1BUG!) but I guess that's a crutch for inadequate hardwa= re. I
was=C2=A0 wondering=C2=A0 whether=C2=A0 instead of buying a larger toroid, = which seem
only=C2=A0 to=C2=A0 be=C2=A0 available=C2=A0 from the US at high cost, I co= uld wind an air
cored=C2=A0 coil=C2=A0 of=C2=A0 similar=C2=A0 inductance. But I am unsure w= hether it would
have the required "Q" factor. Your opinions please? Thanks,

Also=C2=A0 I=C2=A0 am=C2=A0 wondering,=C2=A0 looking=C2=A0 at the Micrometa= ls site, whether the
current -2 material can be bettered by using -3 material?

http://www.w1vd.com/LPF.pdf

and info on frequency range of these cores is at: http://toroids.info/

=C2=A0
--
Best regards,
Chris=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 = =C2=A0 =C2=A0 =C2=A0 mailto:dead.fets@gmail.com




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