Return-Path: Received: from mtain-dg04.r1000.mx.aol.com (mtain-dg04.r1000.mx.aol.com [172.29.65.12]) by air-mc07.mail.aol.com (v129.4) with ESMTP id MAILINMC074-a97e4c0e52fd229; Tue, 08 Jun 2010 10:26:05 -0400 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by mtain-dg04.r1000.mx.aol.com (Internet Inbound) with ESMTP id 6CA4138000084; Tue, 8 Jun 2010 10:26:02 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1OLzjP-0001w5-Aq for rs_out_1@blacksheep.org; Tue, 08 Jun 2010 15:24:43 +0100 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1OLzjO-0001vw-RC for rsgb_lf_group@blacksheep.org; Tue, 08 Jun 2010 15:24:42 +0100 Received: from cavuit02.kulnet.kuleuven.be ([134.58.240.44]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1OLzjK-0004E0-3R for rsgb_lf_group@blacksheep.org; Tue, 08 Jun 2010 15:24:42 +0100 Received: from smtps01.kuleuven.be (smtpshost01.kulnet.kuleuven.be [134.58.240.74]) by cavuit02.kulnet.kuleuven.be (Postfix) with ESMTP id 0D8EC51C01D for ; Tue, 8 Jun 2010 16:24:28 +0200 (CEST) Received: from ICTS-S-HUB-N2.luna.kuleuven.be (icts-s-hub-n2.luna.kuleuven.be [10.112.9.12]) by smtps01.kuleuven.be (Postfix) with ESMTP id 04AB631E702 for ; Tue, 8 Jun 2010 16:24:28 +0200 (CEST) Received: from ICTS-S-EXC2-CA.luna.kuleuven.be ([10.112.11.13]) by ICTS-S-HUB-N2.luna.kuleuven.be ([10.112.9.12]) with mapi; Tue, 8 Jun 2010 16:24:28 +0200 X-Kuleuven: This mail passed the K.U.Leuven mailcluster From: Rik Strobbe To: "rsgb_lf_group@blacksheep.org" Date: Tue, 8 Jun 2010 16:20:05 +0200 Thread-Topic: Re: RE: COIL WINDING THOUGHT Thread-Index: AcsHFANgP5ib8PRlSeqLO7ht4xZT8AAAa2x7 Message-ID: References: <002001cb070c$99d44b20$0401a8c0@xphd97xgq27nyf> ,<004201cb0713$7c295e10$0401a8c0@xphd97xgq27nyf> In-Reply-To: <004201cb0713$7c295e10$0401a8c0@xphd97xgq27nyf> Accept-Language: nl-NL, nl-BE Content-Language: nl-BE X-MS-Has-Attach: X-MS-TNEF-Correlator: acceptlanguage: nl-NL, nl-BE MIME-Version: 1.0 X-KULeuven-Information: Katholieke Universiteit Leuven X-KULeuven-Scanned: Found to be clean X-KULeuven-Envelope-From: rik.strobbe@fys.kuleuven.be X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001 Subject: LF: RE: Re: RE: COIL WINDING THOUGHT Content-Type: multipart/alternative; boundary="_000_BF4A524700075746A6467658DFC7102C5107CB1264ICTSSEXC2CAlu_" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.5 required=5.0 tests=HTML_40_50,HTML_MESSAGE, TO_ADDRESS_EQ_REAL 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: 3039ac1d410c4c0e52fa2405 X-AOL-IP: 193.82.116.20 X-Mailer: Unknown (No Version) --_000_BF4A524700075746A6467658DFC7102C5107CB1264ICTSSEXC2CAlu_ Content-Type: text/plain; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable Just had a look at a roll of 8 stranded wire (Belden) : it is rated 300Vrm= s Assuming an antenna capacitance of 500pF (=3D 35kOhm at 9kHz) you only ne= ed 8.5mA through the coil to generate 300V. 73, Rik ON7YD ________________________________ Van: owner-rsgb_lf_group@blacksheep.org [owner-rsgb_lf_group@blacksheep.or= g] namens mal hamilton [g3kevmal@talktalk.net] Verzonden: dinsdag 8 juni 2010 16:04 Aan: rsgb_lf_group@blacksheep.org Onderwerp: LF: Re: RE: COIL WINDING THOUGHT Jim and Co will hardly be involved with 30kv more like 3kv or less They will let us know g3kev ----- Original Message ----- From: Rik Strobbe To: rsgb_lf_group@blacksheep.org Sent: Tuesday, June 08, 2010 2:47 PM Subject: LF: RE: COIL WINDING THOUGHT Beware of the very high voltages between the strands. Stefan mentioned up to 30kV loading coil voltage, I guess even a fraction= of this voltage will cause arcing between the strands In addition the high stray capacitance will reduce the Q. 73, Rik ON7YD ________________________________ Van: owner-rsgb_lf_group@blacksheep.org [owner-rsgb_lf_group@blacksheep.org] namens mal hamilton [g3kevma= l@talktalk.net] Verzonden: dinsdag 8 juni 2010 15:15 Aan: rsgb Onderwerp: LF: COIL WINDING THOUGHT All vlf men Instead of winding miles of single strand insulated wire to achive the req= uired inductance, use instead insulated multi strand wire and series the= strands, normally the individual strands have coloured insulation and con= venient to connect in series. also gather up all the ferrite cores you can find put into a suitable container= and insert into coil. The above idea might save some coil winding time. another thouight while I am composing Litz wire. Get hold of some old Decca coils ( I have a couple) find the beginning and= end and do the same as above, this however is more difficult although ind= ividually insulated they are all the same colour, but with a meter to iden= tify each strand it can be done de mal/g3kev --_000_BF4A524700075746A6467658DFC7102C5107CB1264ICTSSEXC2CAlu_ Content-Type: text/html; charset="iso-8859-1" Content-Transfer-Encoding: quoted-printable
Just had a look at a roll of 8 stranded wire (Belden) : it= is rated 300Vrms
Assuming  an antenna cap= acitance of 500pF (=3D 35kOhm at 9kHz) you only need 8.5mA through the coi= l to generate 300V.
 
73, Ri= k  ON7YD
 
Van: owner-rsgb_= lf_group@blacksheep.org [owner-rsgb_lf_group@blacksheep.org] namens mal ha= milton [g3kevmal@talktalk.net]
Verzonden: dinsdag 8 juni 2010 16:04
Aan: rsgb_lf_group@blacksheep.org
Onderwerp: LF: Re: RE: COIL WINDING THOUGHT

Jim and Co will hardly be involved wi= th 30kv more like 3kv or less
They will let us know
g3kev
 
 
----- Original Message -----
Sent: Tuesday, June 08, 2010 2:47= PM
Subject: LF: RE: COIL WINDING THOUG= HT

Beware of the very high voltages between the strands.
Stefan mentioned up to 30kV loading= coil voltage, I guess even a fraction of this voltage will cause arcing= between the strands
In addition the high stray capacitan= ce will reduce the Q.
 
73, Rik  ON7YD
 
Van: owner-rsgb_lf_group@blacksheep.org [owner-rsgb_lf_group@blacksheep.org= ] namens mal hamilton [g3kevmal@talktalk.net]
Verzonden: dinsdag 8 juni 2010 15:15
Aan: rsgb
Onderwerp: LF: COIL WINDING THOUGHT

All vlf men
Instead of winding miles of single st= rand insulated wire to achive the required inductance, use instead insulat= ed multi strand wire and series the strands, normally the individual stran= ds have coloured insulation and convenient to connect in series.
also
gather up all the ferrite cores you= can find put into a suitable container and insert into coil.
The above idea might save some coil= winding time.
 
another thouight while I am composing=
 
Litz wire.
 
Get hold of some old Decca coils ( I= have a couple) find the beginning and end and do the same as above, this= however is more difficult although individually insulated they are all th= e same colour, but with a meter to identify each strand it can be done
 
de mal/g3kev
 
--_000_BF4A524700075746A6467658DFC7102C5107CB1264ICTSSEXC2CAlu_--