Message-ID: <041C5051F6E04ACDAD3DAC6252BABD52@gnat>
From: "Alan Melia" <alan.melia@btinternet.com>
To: <rsgb_lf_group@blacksheep.org>
References: <51BF39F4.5050500@iup.uni-heidelberg.de>
Date: Mon, 17 Jun 2013 18:34:43 +0100
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Subject: LF: Re: LF propagation
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I think you have be carefull interpreting this paper....the term "LF" would 
seem to refer to low HF though my German is not good enough to understand it 
fully. The ionospheric effects at these higher frequencies are completely 
different to what happens below 500kHz

There are so called "focussing" effects and effects due to ionospheric 
"tilt".....but there also other effects at LF. It is easy to be led astray 
relying perhaps only on amateur transmissions. I recollect over long periods 
the best times at 136kHz were either just after sunset, or just before dawn 
....few good periods seemed to happen around dark period at the receive site 
(03:00 local time) Modern beacons and auto logging could definitely add to 
knowledge in this area. However there are also questions......nothing will 
be received if the transmitter has stopped transmitting, but it will look 
like poor propagation.

Alan
G3NYK

----- Original Message ----- 
From: "Stefan Schäfer" <Stefan.Schaefer@iup.uni-heidelberg.de>
To: <rsgb_lf_group@blacksheep.org>
Sent: Monday, June 17, 2013 5:31 PM
Subject: LF: LF propagation


> Hi all,
>
> I just want to share this link, 
> http://www.vfo-magazin.de/1999/10/auswirkungen-der-sonnenfinsternis-auf-das-langwellenband/
>
> There is a picture which shows nicely why the best S/N of a LF DX signal 
> is achieved just before the sunrise at the TX location, when the RX 
> station is in the west, as we can see daily in TA detections. If German is 
> not your language, just use google translate.
>
> 73, Stefan/DK7FC
>