Return-Path: Received: from post.thorcom.com (post.thorcom.com [195.171.43.25]) by mtain-dk03.r1000.mx.aol.com (Internet Inbound) with ESMTP id D18F338000096; Wed, 28 Mar 2012 13:05:15 -0400 (EDT) Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1SCwHe-0005NH-C2 for rs_out_1@blacksheep.org; Wed, 28 Mar 2012 18:03:42 +0100 Received: from [195.171.43.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1SCwHd-0005N8-SE for rsgb_lf_group@blacksheep.org; Wed, 28 Mar 2012 18:03:41 +0100 Received: from out1.ip04ir2.opaltelecom.net ([62.24.128.240]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1SCwHb-0006Q3-JQ for rsgb_lf_group@blacksheep.org; Wed, 28 Mar 2012 18:03:41 +0100 X-IronPort-Anti-Spam-Filtered: true X-IronPort-Anti-Spam-Result: ApMBAMJDc09cGScG/2dsb2JhbAANMAi7fAEBAQEDZxENBAsJCAQBAQEJFggHCQMCAQIBNAkIEwYCAQEFiAy7FYp0hh4EjgKadA X-IronPort-AV: E=Sophos;i="4.75,332,1330905600"; d="scan'208,217";a="366753342" Received: from host-92-25-39-6.as13285.net (HELO [192.168.2.4]) ([92.25.39.6]) by out1.ip04ir2.opaltelecom.net with ESMTP; 28 Mar 2012 18:03:33 +0100 Message-ID: <4F734461.1070501@talktalk.net> Date: Wed, 28 Mar 2012 18:03:29 +0100 From: qrss User-Agent: Mozilla/5.0 (Windows NT 5.1; rv:11.0) Gecko/20120312 Thunderbird/11.0 MIME-Version: 1.0 To: rsgb_lf_group@blacksheep.org References: In-Reply-To: X-Spam-Score: 1.4 (+) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001,RATWARE_GECKO_BUILD=1.426 Subject: Re: LF: RE: DF6NM on 8970.002 Content-Type: multipart/alternative; boundary="------------050403050909030106020204" X-Spam-Checker-Version: SpamAssassin 2.63 (2004-01-11) on post.thorcom.com X-Spam-Level: X-Spam-Status: No, hits=0.7 required=5.0 tests=HTML_20_30,HTML_FONTCOLOR_BLUE, HTML_FONTCOLOR_UNKNOWN,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: 0:2:495181888:93952408 x-aol-sid: 3039ac1db4074f7344cb20a8 X-AOL-IP: 195.171.43.25 X-AOL-SPF: domain : blacksheep.org SPF : none This is a multi-part message in MIME format. --------------050403050909030106020204 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit Oh memories, including the BY100 diode. Eddie On 28/03/2012 17:19, Dave G3WCB. wrote: > Hi, Markus, LF, > Bentley accoustics produced the "Ionofane"loudspeaker, that used a > corona or plasma discharge as a sound source. > Perhaps you should consider modulating your carrier with some music, > for the amusement of the neighbours? ;-) > http://www.radiomuseum.org/r/faneacoust_ionofane_601.html > 73, dave G3WCB IO91RM > > -----Original Message----- > *From:* owner-rsgb_lf_group@blacksheep.org > [mailto:owner-rsgb_lf_group@blacksheep.org]*On Behalf Of *Markus > Vester > *Sent:* 27 March 2012 22:23 > *To:* rsgb_lf_group@blacksheep.org > *Subject:* VLF: DF6NM on 8970.002 > > It's a beautiful night! At 20:25, I have started up a straight > carrier on 8970.002 Hz (DHO locked). If all stays well I will > leave it on until after sunrise. > An interesting observation on the side: In the first few minutes, > I drove the amp up to 400 mA antenna current. A little corona > became visible near the ends of two of the three topload wires - > it wasn't very bright, not unlike 3rd magnitude stars when viewed > from the ground 10 m below. But the 9 kHz sound from > antenna itself could be heard quite loudly, which is a potential > cause for neighbourhood trouble. > Then I reduced the drive to 350 mA where the corona disappeared > completely. So did the noise, the antenna became absolutely quiet! > All that was left was a little noise from the coil in the dustbin > on the balcony, and the transformer indoors. Thus the predominant > cause for a squeaking antenna must be corona. The fact that it can > be heard at 9 rather than 18 kHz demonstrates that the discharge > must have an asymmetric dependence on the voltage polarity. > At the same time, wideband electrical noise on the nearby LF > grabber antenna went down by 20 dB. > BTW If you like you can actually read my VLF frequency > from an alias line on the LF TA grabber: It is created by the 24th > VLF harmonic, intermodulating with DCF 77, thus appearing on 24 x > 8970.002 - 77500 = 137780.048 Hz. > Best regards, > Markus (DF6NM) > --------------050403050909030106020204 Content-Type: text/html; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Oh memories, including the BY100 diode.

Eddie

On 28/03/2012 17:19, Dave G3WCB. wrote:
Hi, Markus, LF,
 
Bentley accoustics produced the "Ionofane"loudspeaker, that used a corona or plasma discharge as a sound source.
 
Perhaps you should consider modulating your carrier with some music, for the amusement of the neighbours? ;-)
 
 
73, dave G3WCB IO91RM
-----Original Message-----
From: owner-rsgb_lf_group@blacksheep.org [mailto:owner-rsgb_lf_group@blacksheep.org]On Behalf Of Markus Vester
Sent: 27 March 2012 22:23
To: rsgb_lf_group@blacksheep.org
Subject: VLF: DF6NM on 8970.002

It's a beautiful night! At 20:25, I have started up a straight carrier on 8970.002 Hz (DHO locked). If all stays well I will leave it on until after sunrise.
 
An interesting observation on the side: In the first few minutes, I drove the amp up to 400 mA antenna current. A little corona became visible near the ends of two of the three topload wires - it wasn't very bright, not unlike 3rd magnitude stars when viewed from the ground 10 m below. But the 9 kHz sound from antenna itself could be heard quite loudly, which is a potential cause for neighbourhood trouble.
 
Then I reduced the drive to 350 mA where the corona disappeared completely. So did the noise, the antenna became absolutely quiet! All that was left was a little noise from the coil in the dustbin on the balcony, and the transformer indoors. Thus the predominant cause for a squeaking antenna must be corona. The fact that it can be heard at 9 rather than 18 kHz demonstrates that the discharge must have an asymmetric dependence on the voltage polarity.
 
At the same time, wideband electrical noise on the nearby LF grabber antenna went down by 20 dB.
 
BTW If you like you can actually read my VLF frequency from an alias line on the LF TA grabber: It is created by the 24th VLF harmonic, intermodulating with DCF 77, thus appearing on 24 x 8970.002 - 77500 = 137780.048 Hz.
 
Best regards,
Markus (DF6NM)

--------------050403050909030106020204--