Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-db01.r1000.mx.aol.com (Internet Inbound) with ESMTP id 8BAF438000094; Sun, 1 Jan 2012 08:49:11 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1RhLln-0001a2-4M for rs_out_1@blacksheep.org; Sun, 01 Jan 2012 13:48:15 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1RhLlm-0001Zt-EC for rsgb_lf_group@blacksheep.org; Sun, 01 Jan 2012 13:48:14 +0000 Received: from mail-we0-f171.google.com ([74.125.82.171]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1RhLlj-0008TY-Ra for rsgb_lf_group@blacksheep.org; Sun, 01 Jan 2012 13:48:14 +0000 Received: by werg1 with SMTP id g1so13264239wer.16 for ; Sun, 01 Jan 2012 05:48:06 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=gamma; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; bh=cdDiZC3rRktqijjKbK9jxv8fsBozhQsMjSXX5YgOj6I=; b=gaPE7yz2ckKndsXCnv/GkQyPGiI82NP7Ys5iMNAhYrAFdnm1uSkwr1NFDEOs/g2YhN E2hZDa4plm7akVXmPQJ8WRFnsqf5jNOMGQFY4J9lGuRi95k5Kj5VXjeZ3/3cGGAOPuMb vnl/v5fop5ncObnAo9uWhY+njq4ANtcrM2NF8= MIME-Version: 1.0 Received: by 10.216.132.98 with SMTP id n76mr25264348wei.36.1325425685947; Sun, 01 Jan 2012 05:48:05 -0800 (PST) Received: by 10.216.90.74 with HTTP; Sun, 1 Jan 2012 05:48:05 -0800 (PST) In-Reply-To: <4F005FF6.7020206@iup.uni-heidelberg.de> References: <01a801ccc878$ef553030$0401a8c0@xphd97xgq27nyf> <4F005FF6.7020206@iup.uni-heidelberg.de> Date: Sun, 1 Jan 2012 08:48:05 -0500 Message-ID: From: "Douglas D. Williams" To: rsgb_lf_group@blacksheep.org X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001 Subject: Re: LF: LF ferrite RX antennas Content-Type: multipart/alternative; boundary=0016e6da98bc2fe55b04b577b743 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 x-aol-global-disposition: G X-AOL-SCOLL-SCORE: 0:2:443991136:93952408 X-AOL-SCOLL-URL_COUNT: 0 X-AOL-SCOLL-AUTHENTICATION: mail_rly_antispam_dkim-m009.2 ; domain : gmail.com DKIM : pass x-aol-sid: 3039ac1d40554f0064565a04 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none --0016e6da98bc2fe55b04b577b743 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Wow! Nice design Stefan. Very neat construction and high Q. I wonder.....if someone were to make a large enough ferrite core antenna (not for portable use), would it even need amplification? The cost and/or size would probably be prohibitive. On another note, is there an archive of this reflector somewhere on the web= ? -Doug 2012/1/1 Stefan Sch=E4fer > Hello Doug, > > LF ferrite RX antennas were built and discussed here a few months ago. > They perform excellent but there is no advantage against a larger loop. F= or > me the real only advantage is the handy dimensions so it can find its pla= ce > in a backpack. > I took a few russian ferrite rods from ebay. > If you want, take a look to some photos i took during constructing my > antenna: > > http://dl.dropbox.com/u/**19882028/LF/DSC04160.JPG > http://dl.dropbox.com/u/**19882028/LF/ferrite%20antenna%**20parts.JPG > http://dl.dropbox.com/u/**19882028/LF/inside.JPG > http://dl.dropbox.com/u/**19882028/LF/Q.jpg > http://dl.dropbox.com/u/**19882028/LF/arrangement.JPG > http://dl.dropbox.com/u/**19882028/LF/LF-P%20RX%20RIG.**JPG > http://dl.dropbox.com/u/**19882028/LF/DK7FC_LF_p_active_** > ferrite_antenna.JPG > http://dl.dropbox.com/u/**19882028/LF/DK7FC-p%20LF%20RX.**jpg > http://dl.dropbox.com/u/**19882028/LF/DK7FC%20LF-p%20RX%**20converter.jpg= > > 73, Stefan/DK7FC > > PS: There is a design of M0BMU as well! > > > > Am 01.01.2012 14:03, schrieb Douglas D. Williams: > >> Mal, >> >> I am currently using an active e-probe antenna that was made by Jack >> Smith at Clifton Laboratories. I asked him to custom modify this one >> to be more sensitive than his standard version below 10 kHz, because I >> plan to use it to try to receive a TA signal on your "dreamer's band". >> He was able to make it quite sensitive down to 3 kHz at the expense of >> using some parts with a lower voltage rating, so I have to be careful >> not to short out the coax, etc. It is located about 15 meters from my >> house and the base of the antenna is a mere 3 meters above ground, and >> about 10 meters from the treeline. >> >> http://i81.photobucket.com/**albums/j231/Goranothos/**antenna.jpg >> >> My receiver is an Icom R75 (with CW filters), preceded by an LF >> Converter of AMRAD design with a TXCO for frequency stability, >> preceded by a 500 kHz low pass filter. >> >> I also have a Wellbrook LFL1010, which is not currently in service, >> but since this season is starting off so well, I may put it back up >> for comparison with the e-probe. >> >> Over the years, I have used several different antennas for LF >> reception, including tuned longwires, homebrew e-probes that I >> constructed, homebrew loops, but I must say I am very impressed with >> the Clifton Labs product, as well as the LFL1010, which I used last >> season. Someday I would like to construct a large ferrite core >> receiving antenna. >> >> 73, >> Doug KB4OER >> >> >> >> >> >> >> >> >> On 1/1/12, mal hamilton wrote: >> >> >>> Doug >>> Nice screen shot from you. You are receiving extremely well. What sort = of >>> antenna do you use. >>> You might also hear/see me on 500 Khz running 10W erp >>> >>> 73 es tnx >>> de mal/g3kev >>> >>> >> > --0016e6da98bc2fe55b04b577b743 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Wow! Nice design Stefan. Very neat construction and high Q.

<= div>I wonder.....if someone were to make a large enough ferrite core antenn= a (not for portable use), would it even need amplification? The cost and/or= size would probably be prohibitive.


On another note, is there an archive of = this reflector somewhere on the web?

-Doug

2012/1/1 Stefan Sch=E4fer <Stefan.Scha= efer@iup.uni-heidelberg.de>
Hello Doug,

LF ferrite RX antennas were built and discussed here a few months ago. They= perform excellent but there is no advantage against a larger loop. For me = the real only advantage is the handy dimensions so it can find its place in= a backpack.
I took a few russian ferrite rods from ebay.
If you want, take a look to some photos i took during constructing my anten= na:

http://dl.dropbox.com/u/19882028/LF/DSC04160.JPG
http://dl.dropbox.com/u/19882028/LF/ferrite%20a= ntenna%20parts.JPG
http://dl.dropbox.com/u/19882028/LF/inside.JPG
htt= p://dl.dropbox.com/u/19882028/LF/Q.jpg
http://dl.dropbox.com/u/19882028/LF/arrangement.JPG
http://dl.dropbox.com/u/19882028/LF/LF-P%20RX%20RIG.<= /u>JPG
http://dl.dropbox.com/u/19882028/LF/DK7= FC_LF_p_active_ferrite_antenna.JPG
http://dl.dropbox.com/u/19882028/LF/DK7FC-p%20LF%20RX.<= u>jpg
http://dl.dropbox.com/u/19882028/LF/DK7FC%2= 0LF-p%20RX%20converter.jpg

73, Stefan/DK7FC

PS: There is a design of M0BMU as well!



Am 01.01.2012 14:03, schrieb Douglas D. Williams:
Mal,

I am currently using an active e-probe antenna that was made by Jack
Smith at Clifton Laboratories. I asked him to custom modify this one
to be more sensitive than his standard version below 10 kHz, because I
plan to use it to try to receive a TA signal on your "dreamer's ba= nd".
He was able to make it quite sensitive down to 3 kHz at the expense of
using some parts with a lower voltage rating, so I have to be careful
not to short out the coax, etc. It is located about 15 meters from my
house and the base of the antenna is a mere 3 meters above ground, and
about 10 meters from the treeline.

http://i81.photobucket.com/albums/j231/Goranothos/<= u>antenna.jpg

My receiver is an Icom R75 (with CW filters), preceded by an LF
Converter of AMRAD design with a TXCO for frequency stability,
preceded by a 500 kHz low pass filter.

I also have a Wellbrook LFL1010, which is not currently in service,
but since this season is starting off so well, I may put it back up
for comparison with the e-probe.

Over the years, I have used several different antennas for LF
reception, including tuned longwires, homebrew e-probes that I
constructed, =A0homebrew loops, but I must say I am very impressed with
the Clifton Labs product, as well as the LFL1010, which I used last
season. Someday I would like to construct a large ferrite core
receiving antenna.

73,
Doug KB4OER








On 1/1/12, mal hamilton<g3kevmal@talktalk.net> =A0wrote:
=A0
Doug
Nice screen shot from you. You are receiving extremely well. What sort of antenna do you use.
You might also hear/see me on 500 Khz running 10W erp

73 es tnx
de mal/g3kev
=A0 =A0


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