Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-mk03.r1000.mx.aol.com (Internet Inbound) with ESMTP id 1003138000187; Sun, 13 May 2012 13:39:08 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1STckI-0000g9-Ub for rs_out_1@blacksheep.org; Sun, 13 May 2012 18:38:14 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1STckI-0000g0-94 for rsgb_lf_group@blacksheep.org; Sun, 13 May 2012 18:38:14 +0100 Received: from mail-qc0-f171.google.com ([209.85.216.171]) by relay1.thorcom.net with esmtps (TLSv1:RC4-SHA:128) (Exim 4.77) (envelope-from ) id 1STckF-0007y9-Ei for rsgb_lf_group@blacksheep.org; Sun, 13 May 2012 18:38:13 +0100 Received: by qcsp15 with SMTP id p15so5249807qcs.16 for ; Sun, 13 May 2012 10:38:09 -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=20120113; h=mime-version:in-reply-to:references:date:message-id:subject:from:to :content-type; bh=sT5PJGIIdrwvSX8nXlldj6TvZJzI8DDKXavMAmol22E=; b=gQc16l7y0F5q4yaTa0m4wI4c5jxk1tdMlrRzPqjjUqwd/pUpM1iKjcUpEm3LKepquB Bj5+AN59UHTgP3UmA7C4lLeZqXMA0ysFKNVnnpnJgwitrTK1hFa8fR6PX8ia1KfsKU9q 8yiDBN4BDoV8BsV7dVpkpISOpcGXyYdqfnatGeCaf70R0vS3+z8OjJ/OpCM4NAFfV42y l8OzBoJh89iDNbWEdx76AP8xg+ylClPF0Nd4OdU2plUGfh3fB7m6DulunFAiywim0Eye wHn//QEWFPsg31qj/6eN0TUlH/Wf3fgVk7SeKr+q75VFBA6MsYZRGiEYCgp08Or2g5N0 IGeA== MIME-Version: 1.0 Received: by 10.224.58.209 with SMTP id i17mr8283275qah.95.1336930689170; Sun, 13 May 2012 10:38:09 -0700 (PDT) Received: by 10.229.94.140 with HTTP; Sun, 13 May 2012 10:38:09 -0700 (PDT) Received: by 10.229.94.140 with HTTP; Sun, 13 May 2012 10:38:09 -0700 (PDT) In-Reply-To: <4FAFEA71.8030700@iup.uni-heidelberg.de> References: <4FAFEA71.8030700@iup.uni-heidelberg.de> Date: Sun, 13 May 2012 13:38:09 -0400 Message-ID: From: Warren Ziegler To: rsgb_lf_group@blacksheep.org X-Spam-Score: 2.0 (++) X-Spam-Report: Spam detection software, running on the system "relay1.thorcom.net", has identified this incoming email as possible spam. The original message has been attached to this so you can view it (if it isn't spam) or label similar future email. If you have any questions, see the administrator of that system for details. Content preview: Hi Stefan, Your RX antenna looks very similar to the K9AY which has been used Very successfully by many LF /MF operators for years. It is a little difficult for me to picture the details as I am looking at it on my phone. An excellent web site for such antennas is Dallas Langford's Yahoo group, he has spent years optimizing similar antennas and has achieved results superior to beverage antennas with some of phased loops. I will send a link if you are interested when I get home. 73 Warren K2ORS [...] Content analysis details: (2.0 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.7 RCVD_IN_DNSWL_LOW RBL: Sender listed at http://www.dnswl.org/, low trust [209.85.216.171 listed in list.dnswl.org] 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (wd2xgj[at]gmail.com) -0.0 SPF_PASS SPF: sender matches SPF record 2.6 FU_COMMON_SUBS2 URI: Sub-dir seen often in spam (2). 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: ad8e5dd63f7497fd9d71d15044db2e2b Subject: Re: LF: Cardioid RX antenna for LF... Content-Type: multipart/alternative; boundary=20cf3074b01ed13de104bfee6e94 X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: * X-Spam-Status: No, hits=1.6 required=5.0 tests=CELL_PHONE_BOOST,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: 0:2:433645440:93952408 X-AOL-SCOLL-URL_COUNT: 0 X-AOL-SCOLL-AUTHENTICATION: mail_rly_antispam_dkim-d009.1 ; domain : gmail.com DKIM : pass x-aol-sid: 3039ac1d61874faff1bc0159 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none --20cf3074b01ed13de104bfee6e94 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable Hi Stefan, Your RX antenna looks very similar to the K9AY which has been used Very successfully by many LF /MF operators for years. It is a little difficult for me to picture the details as I am looking at it on my phone. An excellent web site for such antennas is Dallas Langford's Yahoo group, he has spent years optimizing similar antennas and has achieved results superior to beverage antennas with some of phased loops. I will send a link if you are interested when I get home. 73 Warren K2ORS 73 K2ORS On May 13, 2012 1:11 PM, "Stefan Sch=E4fer" < Stefan.Schaefer@iup.uni-heidelberg.de> wrote: > Hello Group, > > I've just started to play a bit in EZNEC, trying to simulate a receive > loop antenna for the new YV7MAE grabber. http://dl.dropbox.com/u/** > 74746618/LF/YV7MAE_LF_Grabber.**html... still using a wire receive antenna with excellen= t results but now a > directional antenna is needed. > > So i modelled a loop with a possible shape and a ground connection. Then = i > added a R on the far end of the source. The results of the elevation and = 3D > plot are surprising good. Maybe i have done a mistake in modelling? Optim= al > performance was obtained at R =3D 8 kOhm. This resulted in the best F/B a= nd > beamwidth... Results of ZENEC are here: http://dl.dropbox.com/u/** > 19882028/LF/Cardioid%20for%**20LF.png > > Any ideas, experiance or advice? > > I guess a preamp is needed when such a antenna is used. The typical 1:9 > un-un does not look useful for me... > > 73, Stefan/DK7FC > > --20cf3074b01ed13de104bfee6e94 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: quoted-printable

Hi Stefan,
Your RX antenna looks very similar to the K9AY which has been used
Very successfully by many LF /MF operators for years.=A0=A0 It is a little = difficult for me to picture the details as I am looking at it on my phone.= =A0 An excellent web site for such antennas is Dallas Langford's Yahoo = group, he has spent years optimizing similar antennas and has achieved resu= lts superior to beverage antennas with some of phased loops.
I will send a link if you are interested when I get home.
73 Warren K2ORS

73 K2ORS

On May 13, 2012 1:11 PM, "Stefan Sch=E4fer&= quot; <Stefan.S= chaefer@iup.uni-heidelberg.de> wrote:
Hello Group,

I've just started to play a bit in EZNEC, trying to simulate a receive = loop antenna for the new YV7MAE grabber. http://dl.dropbox.co= m/u/74746618/LF/YV7MAE_LF_Grabber.html ... still using a = wire receive antenna with excellent results but now a directional antenna i= s needed.

So i modelled a loop with a possible shape and a ground connection. Then i = added a R on the far end of the source. The results of the elevation and 3D= plot are surprising good. Maybe i have done a mistake in modelling? Optima= l performance was obtained at R =3D 8 kOhm. This resulted in the best F/B a= nd beamwidth... Results of ZENEC are here: http://dl.dropbox= .com/u/19882028/LF/Cardioid%20for%20LF.png

Any ideas, experiance or advice?

I guess a preamp is needed when such a antenna is used. The typical 1:9 un-= un does not look useful for me...

73, Stefan/DK7FC

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