Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-dh02.r1000.mx.aol.com (Internet Inbound) with ESMTP id 8B94F38000081; Mon, 14 May 2012 17:09:24 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1SU2VG-0000kH-TS for rs_out_1@blacksheep.org; Mon, 14 May 2012 22:08:26 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1SU2VG-0000k7-4W for rsgb_lf_group@blacksheep.org; Mon, 14 May 2012 22:08:26 +0100 Received: from mailout-de.gmx.net ([213.165.64.23]) by relay1.thorcom.net with smtp (Exim 4.77) (envelope-from ) id 1SU2VD-0006zK-Fb for rsgb_lf_group@blacksheep.org; Mon, 14 May 2012 22:08:24 +0100 Received: (qmail invoked by alias); 14 May 2012 21:08:21 -0000 Received: from p4FD0BAB1.dip.t-dialin.net (EHLO Clemens04) [79.208.186.177] by mail.gmx.net (mp019) with SMTP; 14 May 2012 23:08:21 +0200 X-Authenticated: #17214767 X-Provags-ID: V01U2FsdGVkX1+PApUlqAiPljlB51JO0LaQlHa8YHN/zVV97EekRm q/nZBTZqoequNc Message-ID: <009b01cd3215$b135d690$1502a8c0@Clemens04> From: "Clemens Paul" To: References: <4FAFEA71.8030700@iup.uni-heidelberg.de><4FB01B8C.8050004@gmx.de><3f9e01cd3157$72c9dc80$1502a8c0@Clemens04> Date: Mon, 14 May 2012 23:07:30 +0200 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.3664 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.3664 X-Y-GMX-Trusted: 0 X-Spam-Score: -0.0 (/) 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: Warren, I've buried out the article which was pubished in QST Oct 2010 and carefully studied again. Below you see a short excerpt from the text: "Results: Forward gain with 180 feet of feeder, assuming a 2:1 VSWR, was predicted to vary from -28.6 dBi at 1.8 MHz to -6.4 dBi at 10.1 MHz and this appears to have been achieved. On all bands noise from the OS antenna exceeded that due to the receiver. Additional amplification above that from the preamplifier in the radio may not have been necessary if the antenna was only used in the forward direction. In this application, while receiving off the back, an additional ampli- fication stage may be needed, especially on the lower bands." One point of G3LNP's approach is in fact -as I said - to use the orthogonally steerable null to suppress an interfering station which arrives on the same bearing (and frequency), but at a different vertical angle than the desired station.E.g. he could separate Polish stations from German stations on 160m because their signals arrived at different vertical angles yet on the same bearing.This special feature is only usable when the antenna is receiving off the back. The second point is that in the normal forward mode the *range* of the steerable vertical angle of the backward null can be extended.. While the standard variable resistance can change the angle between 85° and ~40° the variable rectance can extend this range to zero degrees. [...] Content analysis details: (-0.0 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at http://www.dnswl.org/, no trust [213.165.64.23 listed in list.dnswl.org] 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (cpaul[at]gmx.net) -0.0 T_RP_MATCHES_RCVD Envelope sender domain matches handover relay domain -0.0 SPF_PASS SPF: sender matches SPF record 0.0 HTML_MESSAGE BODY: HTML included in message X-Scan-Signature: 80dfd4418e586cee7526d670ae10acbc Subject: Re: LF: Cardioid RX antenna for LF... Content-Type: multipart/alternative; boundary="----=_NextPart_000_0095_01CD3226.56A62ED0" 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: 0:2:488721344:93952408 X-AOL-SCOLL-URL_COUNT: 0 x-aol-sid: 3039ac1d41164fb1748374e6 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none This is a multi-part message in MIME format. ------=_NextPart_000_0095_01CD3226.56A62ED0 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: 8bit Warren, I've buried out the article which was pubished in QST Oct 2010 and carefully studied again. Below you see a short excerpt from the text: ----------------------------------------------- "Results: Forward gain with 180 feet of feeder, assuming a 2:1 VSWR, was predicted to vary from -28.6 dBi at 1.8 MHz to -6.4 dBi at 10.1 MHz and this appears to have been achieved. On all bands noise from the OS antenna exceeded that due to the receiver. Additional amplification above that from the preamplifier in the radio may not have been necessary if the antenna was only used in the forward direction. In this application, while receiving off the back, an additional ampli- fication stage may be needed, especially on the lower bands." -------------------------------------------------------- One point of G3LNP's approach is in fact -as I said - to use the orthogonally steerable null to suppress an interfering station which arrives on the same bearing (and frequency), but at a different vertical angle than the desired station.E.g. he could separate Polish stations from German stations on 160m because their signals arrived at different vertical angles yet on the same bearing.This special feature is only usable when the antenna is receiving off the back. The second point is that in the normal forward mode the *range* of the steerable vertical angle of the backward null can be extended.. While the standard variable resistance can change the angle between 85° and ~40° the variable rectance can extend this range to zero degrees. 73 Clemens DL4RAJ ----- Original Message ----- From: "Warren Ziegler" To: Sent: Monday, May 14, 2012 1:26 AM Subject: Re: LF: Cardioid RX antenna for LF... Clemens, The G3LNP reactance tuned loop receives off the front so it has the same output level as a similar sized K9AY etc, the vertical angle of the rear facing null is steerable by varying the reactance. 73 Warren K2ORS On Sun, May 13, 2012 at 6:26 PM, Clemens Paul wrote: >> BTW, Tony Preedy G3LNP published an article last year in QST which >> had a loop with variable reactance and resistance termination, by >> varying the reactance one could adjust the vertical angle of the main >> lobe. > > > If_I_recall_it_correctly this design uses the *backside* lobe of the K9AY > for vertical beam steering which is as we know a lot, 20dB-30dB,even weaker > than the low gain frontside lobe. > 73 > Clemens > DL4RAJ.. > ----- Original Message ----- From: "Warren Ziegler" > To: > Sent: Sunday, May 13, 2012 11:37 PM > > Subject: Re: LF: Cardioid RX antenna for LF... > > > -- 73 Warren K2ORS WD2XGJ WD2XSH/23 WE2XEB/2 WE2XGR/1 ----- E-Mail ist virenfrei. Von AVG überprüft - www.avg.de Version: 2012.0.2171 / Virendatenbank: 2425/4996 - Ausgabedatum: 13.05.2012 ------=_NextPart_000_0095_01CD3226.56A62ED0 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Warren,
 
I've buried out the article which was pubished=20 in QST Oct 2010
and carefully studied again.
Below you see a short excerpt from the = text:
-----------------------------------------------
=
"Results:
Forward gain with 180 feet of feeder, =
assuming a 2:1=20 VSWR, was predicted to vary
from -28.6 dBi at 1.8 MHz to -6.4 dBi at =
10.1 MHz and this appears to have been
achieved. On all bands = noise from=20 the OS
antenna exceeded that due to the receiver. =
Additional=20 amplification above that from the
preamplifier in the radio may not = have=20 been
necessary if the antenna was only used in the
forward = direction. In=20 this application, while
receiving off the back, an additional=20 ampli-
fication stage may be needed, especially on
the lower=20 bands."
--------------------------------------------------------
One point of G3LNP's approach is in fact = -as I said -=20 to use the orthogonally steerable null
to suppress an interfering station which = arrives on=20 the same bearing (and frequency),
but at a different vertical angle than the = desired=20 station.E.g. he could separate Polish stations
from German stations on 160m because their = signals=20 arrived at different vertical angles yet
on the same bearing.This special feature is only = usable=20 when the antenna is receiving off the = back.  
The second point is that in the normal forward=20 mode the *range* of the steerable vertical angle
of the backward null can be = extended..
While the standard variable resistance can = change the=20 angle between 85=B0 and ~40=B0
the variable rectance can extend this range to = zero=20 degrees.
 
73
Clemens
DL4RAJ 
 
 
----- Original Message -----
From: "Warren Ziegler" <wd2xgj@gmail.com>
To: <rsgb_lf_group@blacksheep.org>
Sent: Monday, May 14, 2012 1:26 AM
Subject: Re: LF: Cardioid RX antenna for=20 LF...

Clemens,

     The G3LNP = reactance tuned=20 loop receives off the front so it has
the same output level as a = similar=20 sized K9AY etc, the vertical angle
of the rear facing null is = steerable by=20 varying the reactance.

73 Warren K2ORS


On Sun, May 13, = 2012 at=20 6:26 PM, Clemens  Paul <cpaul@gmx.net> = wrote:
>> BTW,=20 Tony Preedy G3LNP published an article last year in QST = which
>> had a=20 loop with variable reactance and resistance termination, by
>> = varying=20 the reactance one could adjust the vertical angle of the = main
>>=20 lobe.
>
>
> If_I_recall_it_correctly this design uses = the=20 *backside* lobe of the K9AY
> for vertical beam steering which is = as we=20 know a lot, 20dB-30dB,even weaker
> than the low gain frontside=20 lobe.
> 73
> Clemens
> DL4RAJ..
> ----- Original = Message=20 ----- From: "Warren Ziegler" <wd2xgj@gmail.com>
> = To:=20 <rsgb_lf_group@blacksheep.org>
>=20 Sent: Sunday, May 13, 2012 11:37 PM
>
> Subject: Re: LF: = Cardioid RX=20 antenna for LF...
>
>
>



--
73 = Warren=20 K2ORS
WD2XGJ
WD2XSH/23
WE2XEB/2
WE2XGR/1



-----=
E-Mail=20 ist virenfrei.
Von AVG =FCberpr=FCft - www.avg.de
Version: = 2012.0.2171 /=20 Virendatenbank: 2425/4996 - Ausgabedatum: 13.05.2012=20

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