Return-Path: Received: from mtain-mc01.r1000.mx.aol.com (mtain-mc01.r1000.mx.aol.com [172.29.96.73]) by air-dc03.mail.aol.com (v126.13) with ESMTP id MAILINDC031-85ff4b4c86a861; Tue, 12 Jan 2010 09:26:48 -0500 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by mtain-mc01.r1000.mx.aol.com (Internet Inbound) with ESMTP id A65A838035CDB; Tue, 12 Jan 2010 09:26:38 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1NUhgb-0001B2-2x for rs_out_1@blacksheep.org; Tue, 12 Jan 2010 14:25:33 +0000 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1NUhga-0001At-KZ for rsgb_lf_group@blacksheep.org; Tue, 12 Jan 2010 14:25:32 +0000 Received: from out1.ip07ir2.opaltelecom.net ([62.24.128.243]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1NUhgX-0000sG-RM for rsgb_lf_group@blacksheep.org; Tue, 12 Jan 2010 14:25:32 +0000 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: AtAEAAoVTEtZ8Oh5/2dsb2JhbACCMIEviWsGunSNXINaVgQ X-IronPort-AV: E=Sophos;i="4.49,262,1262563200"; d="scan'208,217";a="433590287" Received: from unknown (HELO xphd97xgq27nyf) ([89.240.232.121]) by out1.ip07ir2.opaltelecom.net with SMTP; 12 Jan 2010 14:25:08 +0000 Message-ID: <001d01ca9393$09a3b640$0401a8c0@xphd97xgq27nyf> From: "mal hamilton" To: References: <249428.56994.qm@web28106.mail.ukl.yahoo.com> Date: Tue, 12 Jan 2010 14:25:05 -0000 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2600.0000 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2600.0000 X-Karma: unknown: X-Spam-Score: 0.1 (/) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001,HTML_TAG_EXIST_TBODY=0.126 Subject: Re: LF:Ice and frost on 600m antenna Content-Type: multipart/alternative; boundary="----=_NextPart_000_001A_01CA9393.09491320" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.9 required=5.0 tests=HTML_30_40,HTML_MESSAGE, HTML_TAG_EXISTS_TBODY 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-sid: 3039ac1d60494b4c869e3ceb X-AOL-IP: 193.82.116.20 ------=_NextPart_000_001A_01CA9393.09491320 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable Pete I use 1.5mm insulated multi strand wire normally but sometimes 2.5mm= but since it is insulated the WX seems to have little effect on it.Th= is is the 1/4 wave inv L TX antenna.Other antennas here use the same= type of wire and again the WX has little effect. My radials are also insulated 2.5 mm. Bare copper wire might be more vunerable to WX changes. de mal/g3kev ----- Original Message -----=20 From: M0FMT=20 To: rsgb_lf_group@blacksheep.org=20 Sent: Tuesday, January 12, 2010 1:51 PM Subject: LF:Ice and frost on 600m antenna Hi LF Group =20 In an attempt to calculating the effect of ICE (Haw frost) on= my antenna I get these results.=20 With a wire diameter of 1.5mm flex weave, it comes out to 1.1= amps for 60 watts RF applied. This is confirmed crudely by observing= a pair of car festoon lamps (12Vx0.5A each) in parallel in the antenn= a up lead glowing to full brightness. With an estimated increase in antenna wire diameter to 10mm ca= used by the Haw frost I did not notice any change in antenna current= by this method. Running the calculation through using a 10mm wire I get 1.2 am= ps and again to an absurd size of 20mm diameter there is virtually no= increase in current. =20 The recent WX at this location has had no noticeable effect on= the antenna. If it did I would suspect leakage through a dodgy insula= tor at the top of the inverted =E2=80=9CL=E2=80=9D up lead. The type I use is a deeply ribbed glass insulator about 8 inch= es long. 73 es GL petefmt =20 ------=_NextPart_000_001A_01CA9393.09491320 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable
Pete
I use 1.5mm insulated multi strand wi= re normally=20 but sometimes 2.5mm but since it is insulated the WX seems to have lit= tle=20 effect on it.This is the 1/4 wave= inv L TX=20 antenna.Other antennas here use the same type of wire and again the WX= has=20 little effect.
My radials are also insulated 2.5 mm.=
Bare copper wire might be more vunera= ble to WX=20 changes.
de mal/g3kev
 
----- Original Message -----
From:=20 M0FMT=
Sent: Tuesday, January 12, 20= 10 1:51=20 PM
Subject: LF:Ice and frost on= 600m=20 antenna


Hi LF Group

 =

In an attem= pt to=20 calculating the effect of ICE (Haw frost) on my antenna I get= these=20 results.=20

With a wire= diameter of=20 1.5mm flex weave, it comes out to 1.1 amps for 60 watts RF app= lied. This=20 is confirmed crudely by observing a pair of car festoon lamps= (12Vx0.5A=20 each) in parallel in the antenna up lead glowing to full brigh= tness.

With an est= imated=20 increase in antenna wire diameter to 10mm caused by the Haw fr= ost I did=20 not notice any change in antenna current by this method.

Running the= calculation=20 through using a 10mm wire I get 1.2 amps and again to an absur= d size of=20 20mm diameter there is virtually no increase in current.

 =

The recent= WX at this=20 location has had no noticeable effect on the antenna. If it di= d I would=20 suspect leakage through a dodgy insulator at the top of the in= verted =E2=80=9CL=E2=80=9D=20 up lead.

The type I= use is a=20 deeply ribbed glass insulator about 8 inches long.


73 es GL=20 petefmt


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