Return-Path: Received: from rly-dg02.mx.aol.com (rly-dg02.mail.aol.com [172.19.151.86]) by air-dg06.mail.aol.com (v123.3) with ESMTP id MAILINDG061-5aa49af18fa252; Wed, 04 Mar 2009 19:12:50 -0500 Received: from post.thorcom.com (post.thorcom.com [193.82.116.20]) by rly-dg02.mx.aol.com (v123.3) with ESMTP id MAILRELAYINDG025-5aa49af18fa252; Wed, 04 Mar 2009 19:12:45 -0500 Received: from majordom by post.thorcom.com with local (Exim 4.14) id 1Lf1Bh-0003Cr-18 for rs_out_1@blacksheep.org; Thu, 05 Mar 2009 00:11:45 +0000 Received: from [193.82.116.32] (helo=relay1.thorcom.net) by post.thorcom.com with esmtp (Exim 4.14) id 1Lf1Bg-0003Ci-L1 for rsgb_lf_group@blacksheep.org; Thu, 05 Mar 2009 00:11:44 +0000 Received: from mailout09.t-online.de ([194.25.134.84]) by relay1.thorcom.net with esmtp (Exim 4.63) (envelope-from ) id 1Lf1Bf-0001BF-Me for rsgb_lf_group@blacksheep.org; Thu, 05 Mar 2009 00:11:44 +0000 Received: from fwd01.aul.t-online.de by mailout09.sul.t-online.de with smtp id 1Lf1Bc-0007ht-00; Thu, 05 Mar 2009 01:11:40 +0100 Received: from [192.168.2.22] (VUgWesZOwhB1O3WAQI2jFrpFVVRXbWgTXc1she4BqkZ56SfRmn0rAN42+LIae5nw0n@[93.196.30.47]) by fwd01.t-online.de with esmtp id 1Lf1BU-0Vc4bw0; Thu, 5 Mar 2009 01:11:32 +0100 MIME-Version: 1.0 From: hajo.brandt.dj1zb@t-online.de To: X-Mailer: T-Online eMail 6.07.0001 Date: 05 Mar 2009 00:11 GMT Message-ID: <1Lf1BU-0Vc4bw0@fwd01.t-online.de> X-ID: VUgWesZOwhB1O3WAQI2jFrpFVVRXbWgTXc1she4BqkZ56SfRmn0rAN42+LIae5nw0n X-TOI-MSGID: e7f45097-8a30-41a3-bab4-522da6783ffa X-Karma: unknown: X-Spam-Score: 0.6 (/) X-Spam-Report: autolearn=disabled,HTML_MESSAGE=0.001,NO_REAL_NAME=0.55,UNPARSEABLE_RELAY=0.001 Subject: Re: LF: Re: capture 67hz.jpg Content-Type: Multipart/Alternative; Boundary="__Next_1236211885_Part33__" 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_40_50,HTML_MESSAGE, NO_REAL_NAME 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-IP: 193.82.116.20 --__Next_1236211885_Part33__ Content-Type: Text/Plain; Charset="ISO-8859-1" Content-Transfer-Encoding: 8Bit "Markus Vester" schrieb: Dear Henny, my QTH is about 400 m from a railway line, and I regularly saw their 16.667 Hz power frequency and several ELF harmonics. The E-fields are relatively strong as the lines normally do not carry a grounded top wire for lightning protection. The "modulation" could be caused by some switching activity. Another origin might be a controlled rectifier on the 50 Hz mains, which could be triggered at a subharmonic frequency. Best regards, Markus, DF6NM Dear Markus, I have even thougth that this "67Hz" in reality might have been 66.667 Hz, and this would open other ideas, such as mixer products between 50 Hz and 16,667 Hz etc. HW? 73 Ha-Jo, DJ1ZB ----- Original Message ----- From: henny van elst To: blacksheep Sent: Wednesday, March 04, 2009 7:43 PM Subject: LF: capture 67hz.jpg Hi,Lf capture unid signal 67hz,but who ? henny pa3cpm best 73s --__Next_1236211885_Part33__ Content-Type: Text/HTML; Charset="ISO-8859-1" Content-Transfer-Encoding: 8Bit T-Online eMail   "Markus Vester" <markusvester@aol.com> schrieb:
Dear Henny,
 
my QTH is about 400 m from a railway line, and I regularly saw their 16.667 Hz power frequency and several ELF harmonics. The E-fields are relatively strong as the lines normally do not carry a grounded top wire for lightning protection. The "modulation" could be caused by some switching activity.
 
Another origin might be a controlled rectifier on the 50 Hz mains, which could be triggered at a subharmonic frequency.
 
Best regards,
Markus, DF6NM


Dear Markus,

I have even thougth that this "67Hz" in reality might have been 66.667 Hz, and this would open other ideas, such as mixer products between 50 Hz and 16,667 Hz etc.

HW?

73 Ha-Jo, DJ1ZB 

----- Original Message -----
Sent: Wednesday, March 04, 2009 7:43 PM
Subject: LF: capture 67hz.jpg

Hi,Lf
capture unid signal 67hz,but who ?
henny pa3cpm
best 73s
  --__Next_1236211885_Part33__--