Return-Path: Received: (qmail 16793 invoked from network); 3 Jul 2003 10:09:54 -0000 Received: from netmail02.services.quay.plus.net (212.159.14.221) by mailstore with SMTP; 3 Jul 2003 10:09:54 -0000 Received: (qmail 29703 invoked by uid 10001); 3 Jul 2003 10:09:53 -0000 Received: from post.thorcom.com (193.82.116.70) by netmail02.services.quay.plus.net with SMTP; 3 Jul 2003 10:09:53 -0000 X-SQ: A Received: from majordom by post.thorcom.com with local (Exim 4.14) id 19Y10E-0001FL-Ki for rsgb_lf_group-outgoing@blacksheep.org; Thu, 03 Jul 2003 11:07:46 +0100 Received: from [212.135.6.14] (helo=smarthost4.mail.uk.easynet.net) by post.thorcom.com with esmtp (Exim 4.14) id 19Y10A-0001FC-9p for rsgb_lf_group@blacksheep.org; Thu, 03 Jul 2003 11:07:42 +0100 Received: from tnt-13-185.easynet.co.uk ([212.134.22.185] helo=erica) by smarthost4.mail.uk.easynet.net with smtp (Exim 4.10) id 19Y107-000PuL-00 for rsgb_lf_group@blacksheep.org; Thu, 03 Jul 2003 11:07:41 +0100 Message-ID: <000a01c3414c$0a940aa0$b91686d4@erica> From: "g3ldo" To: rsgb_lf_group@blacksheep.org References: <001001c33ff6$545b9a60$93e9fc3e@l8p8y6> <002501c34006$e140af00$09dc9384@jka> <001a01c340bb$c8d6fae0$2de9fc3e@l8p8y6> Date: Thu, 3 Jul 2003 11:14:52 +0100 MIME-Version: 1.0 X-Priority: 3 X-MSMail-Priority: Normal X-Mailer: Microsoft Outlook Express 5.50.4522.1200 X-MimeOLE: Produced By Microsoft MimeOLE V6.00.2800.1106 Subject: LF: LF Antennas Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: 8bit X-Spam-Status: No, hits=-0.5 required=5.0tests=REFERENCESversion=2.55 X-Spam-Checker-Version: SpamAssassin 2.55 (1.174.2.19-2003-05-19-exp) X-SA-Exim-Scanned: Yes Sender: Precedence: bulk Reply-To: rsgb_lf_group@blacksheep.org X-Listname: rsgb_lf_group X-SA-Exim-Rcpt-To: rsgb_lf_group-outgoing@blacksheep.org X-SA-Exim-Scanned: No; SAEximRunCond expanded to false John, W1TAG said: ------------------------------- It is occasionally useful to suggest to the newer readers of this reflector that despite the advice given by G3KEV, significant fun and useful knowledge may be had by LF experimenters who have neither a large wallet or a large amount of real estate. -------------------------------- Yes that is true. I5TGC's antenna system is probably the best example of what can be done from a small QTH closely followed by the arrangement at G3XDV. Mal G3KEV said: -------------------------------------- Lots of real estate is not necessary for a 100 ft vertical antenna, about 6ft x 6ft concrete base but the average telescopic tower base is about 1 sq ft. and does not require guys for wire antennas. One insulated radial running around the garden enclosure will work well. against a base loaded or gamma matched mast............... .............If you are happy with you crystal set why change. Any radio amateur serious about LF activities needs a farm or ranch of some sort!!!!!!!! ------------------------------------- A bit of contadiction there. A 100ft (33m) telescopic tower is not a sensible option for a small garden for obvious reasons. Commercial towers for LF, were the tower itself is the antenna element have to be insulated from ground at the base. For a self-supporting structure this means a tower structure similar to that used by Decca. Otherwise it means guying. Gamma or Omega matching systems can be used at 160m but are definitely not on at LF. How long would your matching rod have to be do you think? You need a lot of wire for a resonant insulated radial at 136kHz. My suburban LF antenna has been described as a 'bit of wet string' by Mal but it does seem to work OK. Regards, Peter, G3LDO e-mail Web >