Return-Path: Received: (qmail 23543 invoked from network); 8 Feb 2000 21:32:02 -0000 Received: from unknown (HELO post.thorcom.com) (212.172.148.70) by dimple.core.plus.net.uk with SMTP; 8 Feb 2000 21:32:02 -0000 Received: from majordom by post.thorcom.com with local (Exim 3.02 #1) id 12II5f-0008SP-00 for rsgb_lf_group-outgoing@blacksheep.org; Tue, 08 Feb 2000 21:22:31 +0000 Received: from [195.166.128.23] (helo=merlins.force9.net) by post.thorcom.com with smtp (Exim 3.02 #1) id 12II5b-0008SK-00 for rsgb_lf_group@blacksheep.org; Tue, 08 Feb 2000 21:22:27 +0000 Received: (qmail 275 invoked from network); 8 Feb 2000 21:22:20 -0000 Received: from mayfly.plus.net.uk (HELO mayfly.force9.net) (195.166.128.28) by merlins.plus.net.uk with SMTP; 8 Feb 2000 21:22:20 -0000 Received: (qmail 23082 invoked from network); 8 Feb 2000 21:22:19 -0000 Received: from 136.03-02.quay.dial.plus.net.uk (HELO main) (212.159.70.136) by mayfly.plus.net.uk with SMTP; 8 Feb 2000 21:22:19 -0000 Message-ID: <015601bf727b$43a20a20$0600a8c0@main> From: "Dave" To: "LF Group" References: <18416.200002081752@gemini> Subject: LF: Re: LF Antenna Radiation Date: Tue, 8 Feb 2000 19:28:09 -0000 MIME-Version: 1.0 Content-Type: text/html; charset=windows-1252 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.00.2014.211 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group Sender: Content-transfer-encoding: 8bit

Good work Jim and Dave....

Snippety-snip

>As others have discussed,
>imperfect ground results in a null in the radiation pattern at ground
>level. If the maximum radiation occurs at 20 degrees elevation, you
>would have to position the measuring antenna at a height of 1400
>metres at 4.2km distance in order to measure it.

>The results seem to be in reasonable agreement with the opinions
>a few weeks ago resulting from PA0SE and DK8KW's
>measurements, ie, that people were several dB short of the ERP
>they thought they had.

I always thought that the idea of a "high angle" antenna was interesting, equivalent to a low dipole on topband which is useless locally but gets out OK at a distance. The measured erp would be tiny, but the high angle signal would propagate pretty well. You could then jack up the power to 10 kilowatts and work the world...

If only it were a practical proposition at LF.... ah dreams!

73, Dave G3YXM.