Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by klubnl.pl (8.14.4/8.14.4/Debian-8+deb8u2) with ESMTP id wAOI0ncd023115 for ; Sat, 24 Nov 2018 19:00:51 +0100 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1gQc9j-0004iD-QQ for rs_out_1@blacksheep.org; Sat, 24 Nov 2018 17:55:47 +0000 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1gQc90-0004i2-Ar for rsgb_lf_group@blacksheep.org; Sat, 24 Nov 2018 17:55:02 +0000 Received: from sonic306-3.consmr.mail.bf2.yahoo.com ([74.6.132.42]) by relay1.thorcom.net with esmtp (Exim 4.91_59-0488984) (envelope-from ) id 1gQc8w-0004zi-2u for rsgb_lf_group@blacksheep.org; Sat, 24 Nov 2018 17:54:58 +0000 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=aol.com; s=a2048; t=1543082095; bh=l79854QncFVjMqnpI15HFlO0mgS9/4wEFqwJtPOPdRw=; h=Date:From:To:Subject:References:From:Subject; b=N7vjrP6SipKCAat16bIf63z0RbAaCdmP++pAb8zUnJ1xOLk8nvwTvmH7J/mrI99+IKPUbdX0iAP6AP0j7wsN3u3WvXJQ2ERWGeS8zBlpVuA4WCTptHq/NDGjaCtT3+MPXBdMJdIswsQwcWVutJvp5t9d1+ICfqBRN9TnyoK1HJPMePDuykxI/sQ4fdf/kViq9gGP1XWlVopFSKRG2ALhl/BZnT7CMBPg+rbiXrH+8lwePqbhLVsDmRMq1fev/S3hWFieGPFjz44sCukyjxUI6iL+XcZ+x7mms3yqN3490mdkFB0cDRXoA+ZOUzhWlagcjTg3r2lcyvNxaA4zIm5XTQ== X-YMail-OSG: C53WD4sVM1lT2PxoOhQC2CUAuzXb5ZUvnZ4finRHqFbMHG7qhRAHwD_984A0fJe bBsUN_v98.toxFe4gyjWqpqmbup.dLEs3Vx3XK0.lCWEKsamOONRw1sGfCki_JIgmD9dGFj1ACsU zZz4kA9REUM0AnMHpdPFIbL7nabg6w.ZkXS.TW_Pfn4Pe3.27Qp.xnAaOjF7h4fesiN7Ts1R8Si8 q8tFeNeJr054BRT.xUTaOJf9K1SKdIN7agYpPvvDp1AcU9fWPHsO_JYjtQGbxQ_f4nItS4ORrPks 3_EgnTOjhYwJnj8Oof1m424zNUzgwDbQ_rF23tTD.0pxNRbB5300.A6wcjucYD3LzknCbHJbWq18 lg1RNlFG.7U2_UyyCxiaeK7TehxTTHPPVY.9eHuuFxwy4Hohp0YDM_Z4h0haE.uZM9W3a3ZeiKiZ 0ugyfAGMIH6CvhyYkx2Ep3ExgrEtrAM03E.OpR7J4X0ohdd8Xd18FfWgot7wQn0NhZSEhOGHQmW2 0x0sZ7zWMwBK5OshKYYQcpJx71TNkVlXTJwurD1u21a1d6eYPcN4HPRTLkhpQ4bZBbxfMd0ys9eR 8fyv8fjsNGoEnV28Bfk0r6Dl05tapXxkmSuawpO6QDWTeDawssONKXLEspVXSu5mj7TawdB06chq 8mI6HugSPAEnjY9BcRoBqf.5K97ttg0mE0BZTp2MSpwBLAvsjtrgdbsKnCAN0Ihkurc1eXcrYByM uparB4xvmjEkAnTDb7EcV6qmdyUtjaJDd.ErNquPz99RQVea.wvUbUFczbMIlwqAosYzP4RVIGXm 2RLRsASASKMjLkesyAafH69FWx_dhkK4JFi_pdiViPfN9oK3w43jafLG1iRRZx_hVKyULmom8wFn e4l3txG4t2gzlYoAEHqIzxiQtKzwMMGl0ONaLG7nR2tE_pNgbmFEVDlEYHaM5_apuTQyVYVlAa1j lC6BkZ8V06sRFz927MxHQq_jAZlk- Received: from sonic.gate.mail.ne1.yahoo.com by sonic306.consmr.mail.bf2.yahoo.com with HTTP; Sat, 24 Nov 2018 17:54:55 +0000 Date: Sat, 24 Nov 2018 17:54:51 +0000 (UTC) From: Markus Vester To: rsgb_lf_group@blacksheep.org Message-ID: <1849701513.5496341.1543082091384@mail.yahoo.com> MIME-Version: 1.0 References: <1849701513.5496341.1543082091384.ref@mail.yahoo.com> X-Mailer: WebService/1.1.12729 aolwebmail Mozilla/5.0 (Windows NT 10.0; WOW64; Trident/7.0; Touch; rv:11.0) like Gecko X-Spam-Score: 1.0 (+) X-Spam-Report: Spam detection software, running on the system "relay1.thorcom.net", has NOT identified this incoming email as spam. The original message has been attached to this so you can view it or label similar future email. If you have any questions, see @@CONTACT_ADDRESS@@ for details. Content preview: Hi Chris, Paul, > I have always shorted out any unused turns on the loading coil I would not do that at LF because the induced current in the shorted secondary can be high and will surely increase overall losses. This is an inductive heater! My understanding is that at HF, shortin [...] Content analysis details: (1.0 points, 5.0 required) pts rule name description ---- ---------------------- -------------------------------------------------- -0.0 RCVD_IN_DNSWL_NONE RBL: Sender listed at http://www.dnswl.org/, no trust [74.6.132.42 listed in list.dnswl.org] -0.0 SPF_PASS SPF: sender matches SPF record 0.0 FREEMAIL_FROM Sender email is commonly abused enduser mail provider (markusvester[at]aol.com) 0.0 HTML_MESSAGE BODY: HTML included in message 0.0 T_DKIM_INVALID DKIM-Signature header exists but is not valid 1.0 FREEMAIL_REPLY From and body contain different freemails X-Scan-Signature: 18c242620d7d7b91a1caf5740aa3e326 Subject: Re: LF: No 2200m TX tonight Content-Type: multipart/alternative; boundary="----=_Part_5496340_1204930042.1543082091382" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: *** X-Spam-Status: No, hits=3.2 required=5.0 tests=FORGED_MUA_MOZILLA,HTML_20_30, 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 ------=_Part_5496340_1204930042.1543082091382 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: quoted-printable Hi Chris, Paul, > I have always shorted out any unused turns on the loading coil I would not do that at LF because the induced current in the shorted second= ary can be high and will surely increase overall losses. This is an inducti= ve heater! My understanding is that at HF, shorting low-band coil sections = during high-band operation may be necessary to avoid hitting an unfortunate= =C2=A0self-resonance, but I always felt that this is a compromise I would r= ather avoid. 73, Markus=C2=A0(DF6NM) -----Urspr=C3=BCngliche Mitteilung----- Von: Chris Wilson An: N1BUG Verschickt: Sa, 24. Nov. 2018 18:40 Betreff: Re: LF: No 2200m TX Tonight Hello N1BUG, Paul, I have always shorted out any unused turns on the loading coil with no issues. The matching transformer has floating unused turns though, but I think it's similar to yours, again no problem. The TX horizontal main loop has plastic egg insulators from a cattle fence. They grow green algae over time, and I have had them get iffy. The aerial wire is UK domestic mains insulated 7 strand cable. The insulations seems pretty robust, but given a bad insulator it will arc down the support rope. The loading coil is wound with the same stuff. Saturday, November 24, 2018, 2:39:40 PM, you wrote: > Hi Jay, > I haven't been able to attend a flea market in years. I'm sure I can > find a Cantenna on the auction site, but it won't be for little money. > I've been thinking about an 800W flange resistor on a big heat sink, > but would need to find a big heatsink. Maybe a medium heat sink > packed in ice... or sitting in snow as the case may be! > I did look at water heater elements after you mentioned that a year > ago, but I couldn't find any with a voltage / wattage rating that > looked close to 50 ohms. Also, I am not sure what the resistance vs. > temperature curve looks like on them. I'm torn. Being on a budget it > is always tempting to try the inexpensive route. But on those > occasions when the inexpensive solution fails to work out, one ends > up spending more in the long run. > If I don't find anything with the dummy load tests, I will modify > the coil to eliminate the shorted turn and see if anything changes. > That's an interesting task as one must lay in the snow to remove the > coil from the housing to get at the connections. It's all part of > the continuing adventure... ;-) > I'm going to stay on MF one more night as the trans-Atlantic QSOs > are fun. But I will get the small LF PA fixed up today and be ready > to come back very soon. > 73, > Paul --=20 Best regards, Chris=C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0 =C2=A0= =C2=A0 =C2=A0 =C2=A0 =C2=A0 mailto:dead.fets@gmail.com ------=_Part_5496340_1204930042.1543082091382 Content-Type: text/html; charset=UTF-8 Content-Transfer-Encoding: quoted-printable
Hi Chris, Paul,

> I have always shorted out an= y unused turns on the loading coil

I would not do that at LF because= the induced current in the shorted secondary can be high and will surely i= ncrease overall losses. This is an inductive heater! My understanding is th= at at HF, shorting low-band coil sections during high-band operation may be= necessary to avoid hitting an unfortunate self-resonance, but I alway= s felt that this is a compromise I would rather avoid.


73, Marku= s (DF6NM)



-----Urspr=C3=BCngliche Mitteilung-----
Vo= n: Chris Wilson <dead.fets@gmail.com>
An: N1BUG <rsgb_lf_group@= blacksheep.org>
Verschickt: Sa, 24. Nov. 2018 18:40
Betreff: Re: L= F: No 2200m TX Tonight


Hello N1BUG= ,



Paul, I have always shorted out any unused turns on the loading coil
with no issues. The matching transformer has floating unused = turns
though, but I think it's similar to yours, again no= problem. The TX
horizontal main loop has plastic egg ins= ulators from a cattle fence.
They grow green algae over t= ime, and I have had them get iffy. The
aerial wire is UK = domestic mains insulated 7 strand cable. The
insulations = seems pretty robust, but given a bad insulator it will arc
down the support rope. The loading coil is wound with the
same stuff.



Saturday, November 24, 2018, 2:39:40 PM, you wrote:

> Hi Jay,

&= gt; I haven't been able to attend a flea market in years. I'm sure I can> find a Cantenna on the auction site, but it won't be f= or little money.

> I've been thinki= ng about an 800W flange resistor on a big heat sink,
>= but would need to find a big heatsink. Maybe a medium heat sink
> packed in ice... or sitting in snow as the case may be!

> I did look at water heater elements a= fter you mentioned that a year
> ago, but I couldn't f= ind any with a voltage / wattage rating that
> looked = close to 50 ohms. Also, I am not sure what the resistance vs.
> temperature curve looks like on them. I'm torn. Being on a budget= it
> is always tempting to try the inexpensive route.= But on those
> occasions when the inexpensive solutio= n fails to work out, one ends
> up spending more in th= e long run.

> If I don't find anyth= ing with the dummy load tests, I will modify
> the coi= l to eliminate the shorted turn and see if anything changes.
> That's an interesting task as one must lay in the snow to remove t= he
> coil from the housing to get at the connections. = It's all part of
> the continuing adventure... ;-)

> I'm going to stay on MF one more nig= ht as the trans-Atlantic QSOs
> are fun. But I will ge= t the small LF PA fixed up today and be ready
> to com= e back very soon.

> 73,
> Paul





--
Best regard= s,
Chris             =               mailto:dead.fets@gmail.com



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