Return to KLUBNL.PL main page

rsgb_lf_group
[Top] [All Lists]

LF: DK7FC in Todmorden at 2970 Hz

To: [email protected]
Subject: LF: DK7FC in Todmorden at 2970 Hz
From: Paul Nicholson <[email protected]>
Date: Sun, 26 Mar 2017 20:41:06 +0000
Dkim-signature: v=1; a=rsa-sha256; q=dns/txt; c=relaxed/relaxed; d=abelian.org ; s=default; h=Content-Transfer-Encoding:Content-Type:MIME-Version:Date: Message-ID:To:Subject:From:Sender:Reply-To:Cc:Content-ID:Content-Description: Resent-Date:Resent-From:Resent-Sender:Resent-To:Resent-Cc:Resent-Message-ID: In-Reply-To:References:List-Id:List-Help:List-Unsubscribe:List-Subscribe: List-Post:List-Owner:List-Archive; bh=mtlGmQcWKMEoWCN/G6Xi/3Gx+8aVz6/Gl8/HV+2SjSc=; b=ckgAQ+uktQxhrAvc7ug9QQdjYN a0+RinDrAmJ4MFBbAiJeyNg9fIDtMi8bBWHHJI4zh3XerFErIfJp/Ez8cjqjGRaQRLSYckceFhhEs 0+cXLA55yeTPe892G4n6n+u6P1OCValFwH4kE2r8J6Lje21bsSFoXT645qI2ZKZZVd7E=;
Reply-to: [email protected]
Sender: [email protected]
User-agent: Mozilla/5.0 (X11; Linux x86_64; rv:45.0) Gecko/20100101 Thunderbird/45.5.1
Stefan wrote (10th March):

> Since 16:56 UTC  i'm running 180 mA antenna current
> on (2970 + 7/(24*3600)) Hz, i.e. on 2970.000081 Hz

After coherently stacking 13:00 to 00:00 for 9 days in a
bandwidth of 25.25 uHz I get a clear signal at significance
of around 5 sigma:

 http://abelian.org/vlf/tmp/170326a.png

The peak has S/N 14.0 dB in 25.25uHz, which is -66 dB in
2.5kHz bandwidth.   Signal azimuth is east with the expected
phase angle between E and H antennas.

The days used were 11th to 16th plus 18th to 20th.  Attempting
to include the 17th, or 21st to 23rd reduced the S/N.
Leaving out any of the nine stacks days also reduces the S/N.

The amplitude of each daily contribution is normalised by
the average power in a 20Hz bandwidth around the signal
frequency.

No other bandwidth or daily time range produces a stronger
peak.   14:00 to 19:00 in 55.5 uHz gives about 12dB S/N.

So far, no attempt has been made to compensate for night time
phase delay.

Distance is 881.2 km, approximately 8.7 wavelengths.

--
Paul Nicholson
--

<Prev in Thread] Current Thread [Next in Thread>