Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-dk05.r1000.mx.aol.com (Internet Inbound) with ESMTP id D5B95380000B4; Fri, 12 Aug 2011 14:22:24 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1QrwMY-0006ZG-8f for rs_out_1@blacksheep.org; Fri, 12 Aug 2011 19:21:42 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1QrwMX-0006Z7-Qb for rsgb_lf_group@blacksheep.org; Fri, 12 Aug 2011 19:21:41 +0100 Received: from out1.ip08ir2.opaltelecom.net ([62.24.128.244]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1QrwMV-00072N-Bc for rsgb_lf_group@blacksheep.org; Fri, 12 Aug 2011 19:21:41 +0100 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: Aj4BAHluRU5cHYdB/2dsb2JhbABBgk2Be49jhAFEjwh4gTsFAQEFCAEBAxYzAiwBAQMFAgEDBA0EAQEKIQICFAEEGgYWCAYTCgECAgEBh2CpMJFDhTeBEASCUaEx X-IronPort-AV: E=Sophos;i="4.67,363,1309734000"; d="scan'208,217";a="498901693" Received: from host-92-29-135-65.as13285.net (HELO xphd97xgq27nyf) ([92.29.135.65]) by out1.ip08ir2.opaltelecom.net with SMTP; 12 Aug 2011 19:21:33 +0100 Message-ID: <007801cc591c$a2affa60$0401a8c0@xphd97xgq27nyf> From: "mal hamilton" To: References: <4E4527EF.2000304@iup.uni-heidelberg.de> <52970A62D1224CAF9A966D1743DCBF00@PcMinto> <4E456AB7.6090403@iup.uni-heidelberg.de> Date: Fri, 12 Aug 2011 19:21:20 +0100 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 6.00.2600.0000 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2600.0000 X-Spam-Score: 0.0 (/) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001 Subject: Re: LF: PA3BCA Content-Type: multipart/alternative; boundary="----=_NextPart_000_0075_01CC5925.043D9AF0" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.8 required=5.0 tests=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-global-disposition: G X-AOL-SCOLL-SCORE: 0:2:481571328:93952408 X-AOL-SCOLL-URL_COUNT: 0 x-aol-sid: 3039ac1db4094e456f606f3b X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none This is a multi-part message in MIME format. ------=_NextPart_000_0075_01CC5925.043D9AF0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable My loading coil is 0.5 mH approx wound with 3mm litz wire, it has no = cover just a glass lid on top. Air and rain circulates around it to keep = it cool and weather changes has little effect ie sunshine or showers, = even during stormy windy wx there is very little loading variations.=20 If you have a large loading coil and short antenna wires circumstances = could be different.=20 g3kev ----- Original Message -----=20 From: Stefan Sch=C3=A4fer=20 To: rsgb_lf_group@blacksheep.org=20 Sent: Friday, August 12, 2011 7:02 PM Subject: Re: LF: PA3BCA Hi Minto, Am 12.08.2011 19:42, schrieb Minto Witteveen:=20 How much power were you generating? 73=E2=80=99s, Minto pa3bca It changes all the time. Not even sure since i just have an E field = probe to decouple some power from my TX antenna and feed it to a 50 uA = amperemeter, shunted by a potentiometer. This poti was adjusted to show = 100% full scale when using 120 W RF before some weeks. Now reduced the = parallel R on the poti so it shows just 25 uA then. Got 50 uA anyway by = QRO and more (not sure). So it should be arround 500W. This is -6 dBfs = :-) But the antenna, i.e. the coil and its cover is very lossy it seems. = When there was rain, i have up to twice the losses :-( Need to search = for an alternative cover (mustn't burn, so a water barrel is no = alternative...). 73, Stefan/DK7FC ------=_NextPart_000_0075_01CC5925.043D9AF0 Content-Type: text/html; charset="UTF-8" Content-Transfer-Encoding: quoted-printable =EF=BB=BF
My loading coil is 0.5 mH approx wound with 3mm = litz wire,=20 it has no cover just a glass lid on top. Air and rain circulates around = it to=20 keep it cool and weather changes has little effect ie sunshine or = showers, even=20 during stormy windy wx there is very little loading variations. =
If you have a large loading coil and short = antenna wires=20 circumstances could be different.
g3kev
 
 
----- Original Message -----
From:=20 Stefan = Sch=C3=A4fer
Sent: Friday, August 12, 2011 = 7:02=20 PM
Subject: Re: LF: PA3BCA

Hi Minto,

Am 12.08.2011 19:42, schrieb Minto = Witteveen:=20

How much = power were=20 you generating?

73=E2=80=99s,=20 Minto pa3bca
 


It changes all the = time. Not=20 even sure since i just have an E field probe to decouple some power = from my TX=20 antenna and feed it to a 50 uA amperemeter, shunted by a = potentiometer. This=20 poti was adjusted to show 100% full scale when using 120 W RF before = some=20 weeks. Now reduced the parallel R on the poti so it shows just 25 uA = then. Got=20 50 uA anyway by QRO and more (not sure). So it should be arround 500W. = This is=20 -6 dBfs :-)

But the antenna, i.e. the coil and its cover is = very lossy=20 it seems. When there was rain, i have up to twice the losses :-( Need = to=20 search for an alternative cover (mustn't burn, so a water barrel is no = alternative...).


73, = Stefan/DK7FC
------=_NextPart_000_0075_01CC5925.043D9AF0--