Message-ID: <3E22C382.7F58BD42@att.net>
Date: Mon, 13 Jan 2003 13:47:46 +0000
From: "Dexter McIntyre" <dmcintyre@att.net>
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To: "RSGB LF" <rsgb_lf_group@blacksheep.org>, 
 "lowfer" <lowfer@mailman.qth.net>
Subject: LF: [Fwd: AW: HBG 75 kHz transmitter]
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On several occasions the HBG plot showed an almost instant drop and
return of the signal received here in NC.  These drops didn't look like
propagation events so I emailed the HBG engineer to see if perhaps these
events were transmitter related.  Below is the response I received.

Dex 


Gregor.Dudle@metas.admin.ch wrote:
> 
> Sir
> 
> Thank you very much for your message. It is a nice to hear that our signals
> can be received in North Carolina.
> 
> As for the signal drops, I confirm that our transmitter was down for a short
> time on both occasions you mention in your mail. Both events were due to bad
> weather conditions (strong winds) in the antenna area.
> 
> Jan 7   05:57 to 06:22 (UTC) (I'm recording a measurement every 5 minute,
> therefore the real downtime might be slightly longer)
> Jan 11  06:43 to 07:18 (UTC)
> 
> To complete your records: the transmitter was also down at least 2 times for
> shorter laps (on Jan 6 around 18:00 UTC and 20:37 UTC (I think they these
> failures are also visible on your graph
> http://www.w4dex.com/75khz/hbg07jan03.jpg)
> 
> Do not hesitate to contact me again if you need further information
> 
> Best regards
> 
> Gregor Dudle
> 
> > -----Ursprüngliche Nachricht-----
> > Von:  Dexter McIntyre [SMTP:dmcintyre@att.net]
> > Gesendet am:  11 January 2003 15:47
> > An:   gregor.dudle@metas.admin.ch
> > Betreff:      HBG 75 kHz transmitter
> >
> > Sir,
> >
> > For the past month I have been monitoring and plotting the signal
> > strength of your 75 kHz transmission for LF propagation studies.  I am
> > located in North Carolina, USA.  Today, 11 January and on 7 January, I
> > saw a sudden drop in signal strength of approximately 15 dB.  Both times
> > the signal was down for about half an hour then came back to normal
> > level.  I am trying to determine if these were actually propagation
> > events or if perhaps there was transmitter maintenance being performed
> > during these times.
> >
> > If you are interested in seeing my plots the current one is available
> > at:
> >
> > http://www.w4dex.com/75khz/hbg.jpg
> >
> > The dip at approximately 0640 to 0720 on the 11th of January:
> >
> > http://www.w4dex.com/75khz/hbg11jan03.jpg
> >
> > The dip at approximately 0550 to 0620 on the 7th of January:
> >
> > http://www.w4dex.com/75khz/hbg07jan03.jpg
> >
> > Also a directory of all plots is at:
> >
> > http://www.w4dex.com/75khz/
> >
> > Thank you,
> > Dexter McIntyre
> > Stanfield, NC USA
> > http://www.w4dex.com/