Return-Path: Received: from mtain-md05.r1000.mx.aol.com (mtain-md05.r1000.mx.aol.com [172.29.96.89]) by air-de07.mail.aol.com (v129.10) with ESMTP id MAILINDE073-5ebc4de582877b; Tue, 31 May 2011 20:06:31 -0400 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-md05.r1000.mx.aol.com (Internet Inbound) with ESMTP id 00F583800008D; Tue, 31 May 2011 20:06:29 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1QRYwF-0003T5-RS for rs_out_1@blacksheep.org; Wed, 01 Jun 2011 01:05:31 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1QRYwF-0003Sw-CM for rsgb_lf_group@blacksheep.org; Wed, 01 Jun 2011 01:05:31 +0100 Received: from relay.uni-heidelberg.de ([129.206.100.212]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1QRYwE-0006Hg-1G for rsgb_lf_group@blacksheep.org; Wed, 01 Jun 2011 01:05:31 +0100 Received: from freitag.iup.uni-heidelberg.de (freitag.iup.uni-heidelberg.de [129.206.29.204]) by relay.uni-heidelberg.de (8.14.1/8.14.1) with ESMTP id p5105Tus018294 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES256-SHA bits=256 verify=NO) for ; Wed, 1 Jun 2011 02:05:29 +0200 Received: from [129.206.22.206] (pc206.iup.uni-heidelberg.de [129.206.22.206]) by freitag.iup.uni-heidelberg.de (8.12.11.20060308/8.11.2) with ESMTP id p5105TTB003041 for ; Wed, 1 Jun 2011 02:05:29 +0200 Message-ID: <4DE581D4.3020606@iup.uni-heidelberg.de> Date: Wed, 01 Jun 2011 02:03:32 +0200 From: =?ISO-8859-1?Q?Stefan_Sch=E4fer?= User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.1; de; rv:1.9.1.8) Gecko/20100227 Thunderbird/3.0.3 MIME-Version: 1.0 To: rsgb_lf_group@blacksheep.org References: <824942.16340.qm@web28506.mail.ukl.yahoo.com> In-Reply-To: <824942.16340.qm@web28506.mail.ukl.yahoo.com> X-Spam-Score: 1.6 (+) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001,HTML_TAG_EXIST_TBODY=0.126,RATWARE_GECKO_BUILD=1.426 Subject: Re: LF: VLF - G3XIZ QRT - MF QRV Content-Type: multipart/alternative; boundary="------------010502040203080804080707" 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: 3039ac1d60594de582853fb8 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none X-Mailer: Unknown (No Version) --------------010502040203080804080707 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Hello Chris, Sorry to hear about the short circuit in the coil. Can you repair it by using an isolating paint? I have never had HV problems on my coil so far although using QRO. But surely my wires are longer and so the voltages lower too... I've been using this paint to fix and protect the winding: http://www.elektroradar.de/WebRoot/Store/Shops/ElektroRadar/Products/Images/54/0335254/643340_0335254.jpg It helps to keep the winding at its place when laying in the car. Am 31.05.2011 16:38, schrieb Chris Osborn: > Thank you Stefan, > I hope that you had a pleasant weekend and thank you for looking for > the signal. > I have made some aerial improvements although not as much as I had > anticipated. > I now have an inverted 'L' 48m long and with a mean height 11m > I have far better insulators too. > I shall do some more improvements later. > Sounds good! > My loading coil became unserviceable yesterday at 06.10Z whilst > transmitting. > I think that a flying insect hit the wires and exploded, causing a > short-circuit. > I have had this problem before with insects with high voltages. > I shall try to rectify the coil and then see if my aerial shows an > improvement in signal strength. > Eddie G3ZJO picks me up regularly and his VLF grabber is most useful. > Has anyone an easier way of making a 1.3 H loading coil ? > My present dual-overlaid winding coil took many hours to make and > seems quite unreliable. > The best what you can do is getting more wifre in the air, you know. The more C, the less L. Of course height is an issue. You know how to play the game, just like on LF.. There have been thoughts about ferrite materials but when running QRO there is no alternative for a real air coil i think. Vy 73, Stefan/DK7FC > --------------010502040203080804080707 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Hello Chris,

Sorry to hear about the short circuit in the coil. Can you repair it by using an isolating paint? I have never had HV problems on my coil so far although using QRO. But surely my wires are longer and so the voltages lower too...
I've been using this paint to fix and protect the winding: http://www.elektroradar.de/WebRoot/Store/Shops/ElektroRadar/Products/Images/54/0335254/643340_0335254.jpg
It helps to keep the winding at its place when laying in the car.
Am 31.05.2011 16:38, schrieb Chris Osborn:
Thank you Stefan,
 
I hope that you had a pleasant weekend and thank you for looking for the signal.
 
I have made some aerial improvements although not as much as I had anticipated.
I now have an inverted 'L'  48m long and with a mean height 11m
I have far better insulators too.
I shall do some more improvements later.
Sounds good!
 
My loading coil became unserviceable yesterday at 06.10Z whilst transmitting.
I think that a flying insect hit the wires and exploded, causing a short-circuit.
I have had this problem before with insects with high voltages.
 
I shall try to rectify the coil and then see if my aerial shows an improvement in signal strength.
Eddie G3ZJO picks me up regularly and his VLF grabber is most useful.
 
Has anyone an easier way of making a 1.3 H loading coil ?
My present dual-overlaid winding coil took many hours to make and seems quite unreliable.
The best what you can do is getting more wifre in the air, you know. The more C, the less L. Of course height is an issue. You know how to play the game, just like on LF..

There have been thoughts about ferrite materials but when running QRO there is no alternative for a real air coil i think.

Vy 73, Stefan/DK7FC
--------------010502040203080804080707--