Return-Path: Received: from rly-dd06.mx.aol.com (rly-dd06.mail.aol.com [172.19.141.153]) by air-dd10.mail.aol.com (v124.15) with ESMTP id MAILINDD103-b814a65bf81345; Tue, 21 Jul 2009 09:15:55 -0400 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by rly-dd06.mx.aol.com (v124.15) with ESMTP id MAILRELAYINDD063-b814a65bf81345; Tue, 21 Jul 2009 09:15:48 -0400 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1MTFAk-0007Lj-2s for rs_out_1@blacksheep.org; Tue, 21 Jul 2009 14:14:22 +0100 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1MTFAj-0007La-I3 for rsgb_lf_group@blacksheep.org; Tue, 21 Jul 2009 14:14:21 +0100 Received: from smtp28.orange.fr ([80.12.242.100]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1MTFAS-00069l-QB for rsgb_lf_group@blacksheep.org; Tue, 21 Jul 2009 14:14:05 +0100 Received: from me-wanadoo.net (localhost [127.0.0.1]) by mwinf2807.orange.fr (SMTP Server) with ESMTP id B8DBD7000082 for ; Tue, 21 Jul 2009 15:14:08 +0200 (CEST) Received: from me-wanadoo.net (localhost [127.0.0.1]) by mwinf2807.orange.fr (SMTP Server) with ESMTP id AD9E27000091 for ; Tue, 21 Jul 2009 15:14:08 +0200 (CEST) Received: from acer9412 (ARouen-256-1-75-250.w90-22.abo.wanadoo.fr [90.22.2.250]) by mwinf2807.orange.fr (SMTP Server) with SMTP id 401517000082 for ; Tue, 21 Jul 2009 15:14:08 +0200 (CEST) X-ME-UUID: 20090721131408262.401517000082@mwinf2807.orange.fr Message-ID: From: "F6CWN" To: Date: Tue, 21 Jul 2009 13:14:07 -0000 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2900.5512 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2900.5579 X-Karma: unknown: X-Spam-Score: 3.4 (+++) X-Spam-Report: autolearn=disabled,FORGED_MUA_OUTLOOK=3.36,HTML_MESSAGE=0.001 Subject: Fw: LF: Re: IGBT in 136 KHz TX? Content-Type: multipart/alternative; boundary="----=_NextPart_000_0043_01CA0A05.20F87AF0" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: ** X-Spam-Status: No, hits=2.4 required=5.0 tests=FORGED_MUA_OUTLOOK,HTML_30_40, HTML_MESSAGE 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-IP: 193.82.116.20 ------=_NextPart_000_0043_01CA0A05.20F87AF0 Content-Type: text/plain; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable Subject: Re: LF: Re: IGBT in 136 KHz TX? Hello Laurence and all! =20 I use a two turns rx antenna, it works quite good (more directivity)= . And it are this type of aerial which has just given me the idea of= trying a large coil in TX. Wires in parallel are a very good idea to reduce losses. The problem (I think) is the Q of this aerial. It is necessary to bu= ild an automatic system (PID) to compensate the drift because the aeri= en is very sensitive to the environment variations. This is not easy= because power is high! Two advantages: smaller aerial and bigger directivity. Disadvantage: More copper in air (heavy!), really in case of problem= more important fire hazard. Without counting that the horizontal pola= risation of the field is forgotten. Conclusion: It is again necessary to think... VY 73: Jeff (PS: Ferrites are N67 and not N87!) ----- Original Message -----=20 From: Laurence BY3A-KL1X China=20 To: rsgb_lf_group@blacksheep.org=20 Sent: Tuesday, July 21, 2009 5:47 AM Subject: RE: LF: Re: IGBT in 136 KHz TX? Jeff - The "turns" of the mains WD2XDW loop were just distanced pa= rallel loops running in roughly the same plane to reduce the RF copper= losses and open up the bandwidth a bit - . I did try a couple of "tur= ns" but never managed to get the ommppff field. Interesting given the= fact that some people use 2 turns on their K9AY's successfully - =20 =20 All the loops ends up welded together on lugs and attached to the= tuner. Ive just overhauled the tuner ready to put on line for WE2XPQ= but it will be running lower power for a while as I dont want to star= t a forest fire in Alaska! =20 Back home in KL7 on August 14th again...just need time... =20 laurence BY3A-KL1X Tanggu China 34degC We2XPQ/ x Wd2XDW Wasilla AK =20 Subject: Re: LF: Re: IGBT in 136 KHz TX? Hello Markus and Rick! I have only just acquainted myself with your messages. (Just going out from hospital, big blood pressure problem...) Thanks a lot for precious information, of what make fun still! I recovered some ferrites N87 types which should work in 137 KHZ= . Another subject interests me, it is the possibility of transmitt= ing with a big spool of several turns (a bit as WD2XDW). But EIRP is= much weaker than with a vertical aerial, then it is necessary to "pus= h more" in power! Thanks in advance! 73: Jeff / F6CWN=20 =20 ----------------------------------------------------------------------= ------ Windows Live=99 SkyDrive=99: Store, access, and share your photos.= See how.=20 ------=_NextPart_000_0043_01CA0A05.20F87AF0 Content-Type: text/html; charset="Windows-1252" Content-Transfer-Encoding: quoted-printable
 
Subject: Re: LF: Re: IGBT in 13= 6 KHz=20 TX?

Hello Laurence and all!
 I use=20 a two turns rx antenna, it works quite good (more directivity).= And it=20 are this type of aerial which has just given me the idea of trying&n= bsp;a=20 large coil in TX.
Wires in parallel are a very good= idea to reduce=20 losses.
The problem (I think) is the Q of= this aerial. It=20 is necessary to build an automatic system (PID) to=20 compensate the drift because the aerien is very sensitive= to the=20 environment variations. This is not easy because power is=20 high!
Two advantages: smaller aerial and= bigger=20 directivity.
Disadvantage: More copper in air (h= eavy!), really=20 in case of problem more important fire hazard. Without counting that= the=20 horizontal polarisation of the field is forgotten.
 
Conclusion: It is again necessary= to=20 think...
 
VY 73: Jeff
 
(PS: Ferrites are N67 and not N87!)
 
 
----- Original Message -----
Sent: Tuesday, July 21, 200= 9 5:47=20 AM
Subject: RE: LF: Re: IGBT= in 136 KHz=20 TX?

Jeff - The "turns" of the mains WD2XDW loop we= re just=20 distanced parallel loops running in roughly the same plane to redu= ce the RF=20 copper losses and open up the bandwidth a bit - . I did try= a couple of=20 "turns" but never managed to get the ommppff field. Interesting gi= ven the=20 fact that some people use 2 turns on their K9AY's successfull= y -=20  
 
All the loops ends up welded together  on= lugs and=20 attached to the tuner.  Ive just overhauled the tuner ready= to put on=20 line for WE2XPQ but it will be running lower power for a while as= I dont=20 want to start a forest fire in Alaska!
 
Back home in= KL7 on=20 August 14th again...just need time...
 
laurence
BY3= A-KL1X=20 Tanggu China 34degC
We2XPQ/ x Wd2XDW Wasilla=20 AK
 

 Subject:= Re: LF:=20 Re: IGBT in 136 KHz TX?


Hello Markus and Rick!
 
I have only just acquainted mys= elf with your=20 messages.
(Just going out from hospital, big blood pressure= =20 problem...)
Thanks a lot for precious infor= mation, of=20 what make fun still!
I recovered some ferrites N87= types which=20 should work in 137 KHZ.
Another subject interests me,= it is the=20 possibility of transmitting with a big spool of several turns (a= bit as=20 WD2XDW). But EIRP is much weaker than with a vertical aeria= l, then it=20 is necessary to "push more"  in power!
 
Thanks in advance!
73: Jeff / F6CWN

 

Windows Live=99 SkyDrive=99: Store, access, and share your photos.= See how.
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