Return-Path: Received: from mtain-dj01.r1000.mx.aol.com (mtain-dj01.r1000.mail.aol.com [172.19.187.137]) by air-md08.mail.aol.com (v129.4) with ESMTP id MAILINMD082-8b914d6ec4311a; Wed, 02 Mar 2011 17:26:57 -0500 Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-dj01.r1000.mx.aol.com (Internet Inbound) with ESMTP id 74D0D3800009E; Wed, 2 Mar 2011 17:26:56 -0500 (EST) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1PuuUq-0002W6-Ad for rs_out_1@blacksheep.org; Wed, 02 Mar 2011 22:26:16 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1PuuUp-0002Vx-Rt for rsgb_lf_group@blacksheep.org; Wed, 02 Mar 2011 22:26:15 +0000 Received: from smtp5.freeserve.com ([193.252.22.128]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1PuuUn-0007AQ-3x for rsgb_lf_group@blacksheep.org; Wed, 02 Mar 2011 22:26:15 +0000 Received: from me-wanadoo.net (localhost [127.0.0.1]) by mwinf3418.me.freeserve.com (SMTP Server) with ESMTP id 610AC1C000AD for ; Wed, 2 Mar 2011 23:26:07 +0100 (CET) Received: from me-wanadoo.net (localhost [127.0.0.1]) by mwinf3418.me.freeserve.com (SMTP Server) with ESMTP id 537EF1C000AE for ; Wed, 2 Mar 2011 23:26:07 +0100 (CET) Received: from AGB (unknown [91.109.51.246]) by mwinf3418.me.freeserve.com (SMTP Server) with SMTP id 12AED1C000AD for ; Wed, 2 Mar 2011 23:26:07 +0100 (CET) X-ME-UUID: 20110302222607770.12AED1C000AD@mwinf3418.me.freeserve.com Message-ID: From: "Graham" To: References: In-Reply-To: Date: Wed, 2 Mar 2011 22:26:06 -0000 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal Importance: Normal X-Mailer: Microsoft Windows Live Mail 14.0.8117.416 X-MimeOLE: Produced By Microsoft MimeOLE V14.0.8117.416 X-Antivirus: avast! (VPS 110302-1, 02/03/2011), Outbound message X-Antivirus-Status: Clean X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001 Subject: Re: LF: Corona Discharge - how to prevent ? Content-Type: multipart/alternative; boundary="----=_NextPart_000_00D8_01CBD928.D28A0150" 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 x-aol-global-disposition: G x-aol-sid: 3039cdbc9d054d6ec42f16ea X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none ------=_NextPart_000_00D8_01CBD928.D28A0150 Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Thanks Alan , John. Yes that seems to be the solution , may be a ball would do the= same thing ?.. I was wrangling with the charge distribution angle= .. as to the best way , assuming a sharp point on the ring woul= d still produce the same corona ?=20 The double stacked ring looked a good idea , but is only in= 'one plane' what happens at 90 deg ie in front and behind ...= ? The tube has possibilities, I have some copper brake pipe , that = should do the job .... Pity to quench it, it looks quite impressive in the night ! , (n= ot sure what its doing to the local medium wave reception though...) tnx - G..=20 From: Graham=20 Sent: Wednesday, March 02, 2011 8:32 PM To: rsgb_lf_group@blacksheep.org=20 Subject: LF: Corona Discharge - how to prevent ? Corona Discharge - how to prevent ? Running into corona problems with a small loaded antenna , term= inating as a wire at the far end=20 Q has any one addressed this problem and found a suitable solutio= n ? Apparently more prevalent on 136 khz , this is presenting on 500= k , I can find reference to rounded objects and rings , one bein= g two sets of ring's the second being insulated to reduce the= v/mm stress , but these where part of a high voltage insulator= with the far end earthed , not so in this case, the wire ends= in free space .. Increasing the surface area will distribute the charge , but wi= ll not reduce the stress as this is a generated field as opposed= to a static build up ? Links / ides ? Tnx - Graham . ------=_NextPart_000_00D8_01CBD928.D28A0150 Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Thanks  Alan , John.
 
Yes that  seems  to be the= solution , may=20 be a  ball   would  do  the  same thing= ?.. I=20 was  wrangling with the charge  distribution angle .. as to= the =20 best  way  , assuming a  sharp point on the  ring&= nbsp;=20 would  still  produce the  same  corona  ?=20
 
The  double  stacked = ring =20 looked a  good  idea  , but  is  only = in 'one=20 plane'  what  happens  at  90  deg  ie&n= bsp; in=20 front  and behind ...  ?
 
The tube  has possibilities, I= have some =20 copper brake  pipe , that   should  do the job=20 ....
 
Pity to  quench it, it = ; looks =20 quite impressive  in the  night  !=20 , (not  sure what its doing to the  local
medium wave reception  though...= )
 
tnx - G..

From: Graham
Sent: Wednesday, March 02, 2011 8:32 PM
Subject: LF: Corona Discharge - how to prevent ?

Corona Discharge - how to  preve= nt =20 ?
 
Running  into  corona probl= ems =20 with  a  small  loaded  antenna , terminating = ; as=20 a  wire  at the far  end
 
Q has any one  addressed = this =20 problem and  found a  suitable solution ?
 
Apparently  more  prevalent= on 136 =20 khz , this  is  presenting  on 500k , I can  find&= nbsp;=20 reference  to rounded  objects and  rings , one = being =20 two  sets  of ring's the  second  being  insu= lated=20 to  reduce the  v/mm stress , but these  where  pa= rt of=20 a  high  voltage insulator  with the  far  en= d =20 earthed , not so  in this  case, the  wire  ends= in=20 free  space ..
 
Increasing the  surface  ar= ea =20 will  distribute  the  charge , but  will  no= t =20 reduce the stress  as this  is  a generated  field= as=20 opposed to a  static build up ?
 
Links / ides ?
 
Tnx - Graham .




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