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[195.171.43.25]) by mx.google.com with ESMTP id fw4si6145567wjb.97.2014.01.11.10.23.11 for ; Sat, 11 Jan 2014 10:23:12 -0800 (PST) Received-SPF: neutral (google.com: 195.171.43.25 is neither permitted nor denied by best guess record for domain of owner-rsgb_lf_group@blacksheep.org) client-ip=195.171.43.25; Authentication-Results: mx.google.com; spf=neutral (google.com: 195.171.43.25 is neither permitted nor denied by best guess record for domain of owner-rsgb_lf_group@blacksheep.org) smtp.mail=owner-rsgb_lf_group@blacksheep.org; dkim=pass header.i=@mx.aol.com Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1W233b-0004F3-EA for rs_out_1@blacksheep.org; Sat, 11 Jan 2014 18:13:15 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1W233a-0004Eu-OW for rsgb_lf_group@blacksheep.org; Sat, 11 Jan 2014 18:13:14 +0000 Received: from omr-d01.mx.aol.com ([205.188.252.208]) by relay1.thorcom.net with esmtps (TLSv1:AES256-SHA:256) (Exim 4.77) (envelope-from ) id 1W233Y-0004pp-0E for rsgb_lf_group@blacksheep.org; Sat, 11 Jan 2014 18:13:13 +0000 Received: from mtaout-mab01.mx.aol.com (mtaout-mab01.mx.aol.com [172.26.249.81]) by omr-d01.mx.aol.com (Outbound Mail Relay) with ESMTP id 02103700000A5 for ; Sat, 11 Jan 2014 13:13:10 -0500 (EST) Received: from White (95-91-238-155-dynip.superkabel.de [95.91.238.155]) by mtaout-mab01.mx.aol.com (MUA/Third Party Client Interface) with ESMTPA id E9DC238000081 for ; Sat, 11 Jan 2014 13:13:06 -0500 (EST) Message-ID: From: "Markus Vester" To: References: ,<45C914842E044970AE255AC43CA09FB3@White>, , Date: Sat, 11 Jan 2014 19:13:04 +0100 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal Importance: Normal X-Mailer: Microsoft Windows Live Mail 12.0.1606 X-MimeOLE: Produced By Microsoft MimeOLE V12.0.1606 x-aol-global-disposition: G DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=mx.aol.com; s=20121107; t=1389463989; bh=wdk9WowfKUjcX9GfAcuIzZar/7TFy/ZqVqIydZplLKU=; h=From:To:Subject:Message-ID:Date:MIME-Version:Content-Type; b=jPtIN4DiNPvaiNfxbNIowv5U36ZYpFb/Bd6QDC2b2GyIW1M1JN7pjX2VwVrhBnRlM jljLj+QF9wjzyNBHOiKMBG7P869DnI+XupAEfRgOzXbBxSjw9ZCXDuORBowvYkpDrb z+fRdYpHDGXZmaH7pPY2t0kOrL/eIBMvMxzGe5uI= x-aol-sid: 3039ac1af95152d189b23158 X-AOL-IP: 95.91.238.155 X-Spam-Score: 0.9 (/) 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: Yes. I sneaked a separate ground wire down the chimney to the basement, where PE and heating system are connected to the metal water inlet pipe. On a cold and dry winter day, the antenna resistance at LF (including the coil) is as low as 15 ohms. This probably is probably aided by a Faraday shielding effect from the thermal insulation under the roof, which is covered by a vapor-stop layer consisting of very thin aluminium foil strips - seems the roof is acting as a sort of ground screen. [...] Content analysis details: (0.9 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at http://www.dnswl.org/, no trust [205.188.252.208 listed in list.dnswl.org] 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (markusvester[at]aol.com) -0.0 SPF_PASS SPF: sender matches SPF record -0.1 RP_MATCHES_RCVD Envelope sender domain matches handover relay domain 0.0 HTML_MESSAGE BODY: HTML included in message 0.0 T_DKIM_INVALID DKIM-Signature header exists but is not valid 1.0 FREEMAIL_REPLY From and body contain different freemails X-Scan-Signature: 9b3026b1f8b02ffe2f7d65ee41ac1a6b Subject: Re: VLF: 8270 (antenna and grounding) Content-Type: multipart/alternative; boundary="----=_NextPart_000_0007_01CF0F01.27412B40" 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_40_50,HTML_MESSAGE, MISSING_OUTLOOK_NAME 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 Dies ist eine mehrteilige Nachricht im MIME-Format. ------=_NextPart_000_0007_01CF0F01.27412B40 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Yes. I sneaked a separate ground wire down the chimney to the basement, = where PE and heating system are connected to the metal water inlet pipe. = On a cold and dry winter day, the antenna resistance at LF (including = the coil) is as low as 15 ohms. This probably is probably aided by a = Faraday shielding effect from the thermal insulation under the roof, = which is covered by a vapor-stop layer consisting of very thin aluminium = foil strips - seems the roof is acting as a sort of ground screen. The telescopic rod consists of several sliding sections separated by = insulating plastic rings, which I thought was good. But I was plagued by = erratic partial discharge problems between segments, which sometimes = came and went away with wind-induced bending. Strong noise in my = neighbour's FM radio, and strange krrrk krrrrrk sounds coming out of the = chimney doorlet. In a recent rework, I have connected all segments with = little bolts, and tied the bottom of the mast to ground potential. 73, Markus From: Bob Raide=20 Sent: Saturday, January 11, 2014 6:44 PM To: rsgb_lf_group@blacksheep.org=20 Subject: RE: VLF: 8270 Markus; That is an amazing antenna! That short to work so well at VLF. Evan = for LF but it really works for you. I see no provision for ground = system and would guess you use house plumbing for ground system? =20 -------------------------------------------------------------------------= ------- From: markusvester@aol.com To: rsgb_lf_group@blacksheep.org Date: Sat, 11 Jan 2014 18:26:30 +0100 Subject: Re: VLF: 8270 Bob, it's the same antenna that I use for LF. The mast is a fishing rod on an = aluminium telescopic pole, pushed out of an unused chimney. It carries = three topload legs (N, W and S), about 42 m wire in total (230 pF). The = apex is 20 m AGL or 11 m above the roof, but the effective height is = only 9 m (calibrated at 138 kHz). On VLF frequencies this is probably = even a bit lower due to increased shunting effect from trees. Assuming = heff =3D 0.8 m, radiation resistance on 8.3 kHz would be 0.08 milliohm. = With 60 Watts input, I got 0.3 A and 25 kV rms, and radiated power = (EMRP) would be around 7 microwatts. Here's a sketch of the wire layout and the auxiliary H- and E-field = receive antennas: http://dl.dropboxusercontent.com/u/26404526/Hans-Fallada-59_antennas.jpg = One could actually see the antenna in Google Map's slant view, but the = imagery may have changed since: http://dl.dropboxusercontent.com/u/26404526/googlemaps_df6nm_antenna.jpg http://maps.google.de/maps?ll=3D49.4158,11.1350&z=3D21 Best 73, Markus From: Bob Raide=20 Sent: Saturday, January 11, 2014 5:37 PM To: rsgb_lf_group@blacksheep.org=20 Subject: RE: VLF: 8270 Markus; What are you using for antenna on 8270? =20 -------------------------------------------------------------------------= ------- From: bvgbob@hotmail.com To: rsgb_lf_group@blacksheep.org Date: Sat, 11 Jan 2014 14:28:32 +0100 Subject: RE: VLF: 8270 Hello Markus! Nice signal here, congratulations! Lubos, OK2BVG -------------------------------------------------------------------------= ------- From: markusvester@aol.com To: rsgb_lf_group@blacksheep.org CC: paul@abelian.netcom.co.uk Date: Sat, 11 Jan 2014 13:59:58 +0100 Subject: Re: VLF: 8270 Took the carrier off air at 12:48. Looks like a good trace at OK2BVG, = and a dash with marginal SNR in Todmorden UK.=20 73, Markus From: Markus Vester=20 Sent: Saturday, January 11, 2014 11:33 AM To: rsgb_lf_group@blacksheep.org=20 Subject: VLF: 8270 At 10:23 I have started to transmit a straight carrier on 8270.000 Hz, = estimated ERP around 14 uW. If all stays well, I'll leave it on for a = couple of hours, trying to leave a dash on Lubos' and perhaps Paul's = spectrograms. 73, Markus (DF6NM) ------=_NextPart_000_0007_01CF0F01.27412B40 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Yes. I sneaked a separate ground wire down the chimney = to the=20 basement, where PE and heating system are connected to the=20 metal water inlet pipe. On = a cold and=20 dry winter day, the antenna resistance at LF (including the coil) = is as low=20 as 15 ohms. This probably is probably aided by a Faraday=20 shielding effect from the thermal insulation under the roof, = which is=20 covered by a vapor-stop layer consisting of very thin = aluminium foil=20 strips - seems the roof is acting as a sort of ground = screen.
 
The telescopic rod consists of = several sliding=20 sections separated by insulating plastic rings, which I thought was=20 good. But I was plagued by erratic partial discharge problems = between=20 segments, which sometimes came and went away with wind-induced = bending. Strong noise in my neighbour's FM radio, and strange krrrk = krrrrrk=20 sounds coming out of the chimney doorlet. In a recent rework,=20 I have connected all segments with little bolts, = and tied=20 the bottom of the mast to ground potential.
 
73, Markus

From: Bob Raide
Sent: Saturday, January 11, 2014 6:44 PM
Subject: RE: VLF: 8270

Markus;
That is an amazing antenna!  That short = to work so=20 well at VLF.  Evan for LF but it really works for you.  I = see no=20 provision for ground system and would guess you use house plumbing for = ground=20 system?
 
From: markusvester@aol.com
To: rsgb_lf_group@blacksheep.org=
Date:=20 Sat, 11 Jan 2014 18:26:30 +0100
Subject: Re: VLF: 8270

Bob,
 
it's the same antenna that I use = for LF. The=20 mast is a fishing rod on an aluminium telescopic pole, pushed out of an = unused=20 chimney. It carries three topload legs (N, W and S), about 42 m = wire in=20 total (230 pF). The apex is 20 m AGL or 11 m above the roof, = but the=20 effective height is only 9 m (calibrated at 138 kHz). On VLF = frequencies=20 this is probably even a bit lower due to increased shunting effect from = trees.=20 Assuming heff =3D 0.8 m, radiation resistance on 8.3 kHz would = be 0.08=20 milliohm. With 60 Watts input, I got 0.3 A and 25 kV rms,=20 and radiated power (EMRP) would be around 7 = microwatts.
 
Here's a sketch of the wire layout and = the=20 auxiliary H- and E-field receive antennas:
http://dl.dropboxusercontent.com/u/26404526/Hans-Fallada-= 59_antennas.jpg 
 
One could actually see the = antenna in Google=20 Map's slant view, but the imagery may have changed = since:
http://dl.dropboxusercontent.com/u/26404526/googlemaps_df= 6nm_antenna.jpg
http://maps.google.de/maps?ll=3D49.4158,11.1350&z=3D21
 
Best 73,
Markus

From: Bob = Raide
Sent: Saturday, January = 11, 2014 5:37=20 PM
To: rsgb_lf_group@blacksheep.org
Subject: RE: VLF:=20 8270

Markus;
What are you using = for antenna=20 on 8270?
 
From: bvgbob@hotmail.com
To:=20 rsgb_lf_group@blacksheep.org
Date: Sat, 11 Jan 2014 14:28:32 +0100
Subject: RE: VLF:=20 8270

Hello Markus!
Nice signal here,=20 congratulations!

Lubos, = OK2BVG

From: markusvester@aol.com
To:=20 rsgb_lf_group@blacksheep.org
CC: paul@abelian.netcom.co.uk
Date:=20 Sat, 11 Jan 2014 13:59:58 +0100
Subject: Re: VLF: = 8270

Took the carrier off air at = 12:48. Looks=20 like a good trace at OK2BVG, and a dash with marginal SNR in Todmorden = UK.=20
 
73, Markus
 

From: Markus = Vester=20
Sent: Saturday, = January 11,=20 2014 11:33 AM
To: = rsgb_lf_group@blacksheep.org
Subject: VLF:=20 8270

At 10:23 I have started to = transmit a=20 straight carrier on 8270.000 Hz, estimated ERP around 14 uW. If all = stays well,=20 I'll leave it on for a couple of hours, trying to leave a dash = on Lubos'=20 and perhaps Paul's spectrograms.
 
73, Markus=20 (DF6NM)
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