Return-Path: Received: (qmail 8088 invoked from network); 12 Dec 1999 11:16:31 -0000 Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by 212.159.2.33 with SMTP; 12 Dec 1999 11:16:31 -0000 Received: from majordom by post.thorcom.com with local (Exim 3.02 #1) id 11x7Ot-0006zh-00 for rsgb_lf_group-outgoing@blacksheep.org; Sun, 12 Dec 1999 11:42:51 +0000 Received: from mail1-gui.server.ntli.net ([194.168.222.13]) by post.thorcom.com with esmtp (Exim 3.02 #1) id 11x7Os-0006yE-00 for rsgb_lf_group@blacksheep.org; Sun, 12 Dec 1999 11:42:50 +0000 X-Priority: 3 X-MSMail-Priority: Normal Received: from cableol.co.uk ([194.168.18.88]) by mail1-gui.server.ntli.net (Post.Office MTA v3.1 release PO203a ID# 0-33929U70000L2S50) with ESMTP id AAA20672 for ; Sun, 12 Dec 1999 10:54:50 +0000 Message-ID: <38537D60.6CFF9931@cableol.co.uk> Date: Sun, 12 Dec 1999 10:48:00 +0000 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 From: "Steve Rawlings" X-Mailer: Mozilla 4.04 [en] (Win95; I) MIME-Version: 1.0 To: rsgb_lf_group@blacksheep.org Subject: Re: LF: Re: re: Insulators References: <000701bf4413$99828b40$080e01d5@dave> <003901bf4489$1d3fec00$0600a8c0@main> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 8bit Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Sender: Dave G3YXM wrote: > . . . Just a cautionary note about the use of plastic tubes to support LF > aerials. > Water collects inside the tube (if it is horizontal) and RF then tracks > along it and the whole thing catches fire... I know this! A good point. I've experienced similar problems with tubes when used as insulators. During a telephone conversation with Bill G0AKY, he described a similar 'trick' to that described by Dave G3YMC. Bill cuts his round white plastic tube (e.g. gutter down-pipe, up to 100 mm diameter) into lengths about 30 mm long. He then uses heat to soften the sections into an oval shape. I suppose the overall result is rather like using a cable tie, but may be more UV resistant than the common type of cable tie. Regards to all, Steve GW4ALG