Return-Path: Received: (qmail 3782 invoked from network); 4 May 2003 21:30:24 -0000 Received: from warrior.services.quay.plus.net (212.159.14.227) by mailstore with SMTP; 4 May 2003 21:30:24 -0000 Received: (qmail 20250 invoked from network); 4 May 2003 21:30:28 -0000 Received: from post.thorcom.com (193.82.116.70) by warrior.services.quay.plus.net with SMTP; 4 May 2003 21:30:28 -0000 X-SQ: A Received: from majordom by post.thorcom.com with local (Exim 4.14) id 19CR2f-00084e-6F for rsgb_lf_group-outgoing@blacksheep.org; Sun, 04 May 2003 22:29:05 +0100 Received: from [212.135.6.14] (helo=smarthost4.mail.uk.easynet.net) by post.thorcom.com with esmtp (Exim 4.14) id 19CR2a-00084V-5J for rsgb_lf_group@blacksheep.org; Sun, 04 May 2003 22:29:00 +0100 Received: from tnt-2-101.easynet.co.uk ([195.40.196.101] helo=erica) by smarthost4.mail.uk.easynet.net with smtp (Exim 4.10) id 19CR2Z-0009dS-00 for rsgb_lf_group@blacksheep.org; Sun, 04 May 2003 22:28:59 +0100 Message-ID: <000801c31285$053956a0$65c428c3@erica> From: "g3ldo" To: rsgb_lf_group@blacksheep.org References: <002b01c3109e$081b7440$3704210a@Hugh> Date: Sun, 4 May 2003 22:34:25 +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: Re: Way off subject ... and totally batty Content-Type: text/plain; charset=iso-8859-1; format=flowed Content-Transfer-Encoding: 8bit X-Spam-Status: No, hits=-9.8 required=5.0tests=QUOTED_EMAIL_TEXT,REFERENCESversion=2.53 X-Spam-Checker-Version: SpamAssassin 2.53 (1.174.2.15-2003-03-30-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 Hi Hugh > Has anyone else tried this with their LF/VLF receivers ? > > I have put a microphone on my SLM and have been receiving bats. I used a > tiny electret condenser mic capsule on the input of the D2006, with the > usual 1.5V cell and blocking cap to power the capsule. I was able to pick up > bat sounds up to 55kHz. There were some clicks down at 22.5kHz, and some > twitters around 45kHz. I think they are just the common or garden > Pipistrelle bats. > The first available FFT software for displaying frequency time and amplitude that could be used with a soundcard was Spectrogram, written by R. S. Horne. This software was originally designed for displaying the spectrum of birdsong and different amplitudes were assigned colours. Your bats might make some pretty pictures with this software and a microphone directly on the soundcard. Regards, Peter, G3LDO e-mail Web