Envelope-to: dave@picks.force9.co.uk
Delivery-date: Wed, 22 Jun 2005 17:21:43 +0100
From: "james moritz" <j.r.moritz@herts.ac.uk>
To: rsgb_lf_group@blacksheep.org
Date: Wed, 22 Jun 2005 17:20:14 +0100
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In-Reply-To: <NKEMLGOEKANPNJOBFBAFGEGFCFAA.g4wgt@tiscali.co.uk>
Subject: LF: RE: RE: Rugby Loran QRV
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Dear Gary, LF Group,

I don't think it is a total disaster, although it will certainly make CW
operation much harder for stations in the central part of the UK, and I
guess it will also affect the LF SSB John and the cave radio people use. The
signal from Rugby to your QTH and most of the UK will be mostly ground wave,
so probably not much different between day and night. On the other hand, the
QRN noise level usually rises 10dB or more during the night, so the effect
of the Loran noise will effectively be reduced. I guess where you are you
should get a quite good null with your loop antenna - although the nulls
will also reduce wanted signal levels from other UK and southern European
stations. The same applies at my QTH, plus it will be difficult to null out
both Lessay and Rugby at the same time.

QRSS operation should be little affected provided a signal frequency can be
chosen that is between two Loran lines - but even random frequency selection
should be OK in a majority of cases because there are more gaps than lines.
With signals with BW of more than a few Hz, such as PSK31, "Hell", or the
wider settings of "Jason" and DFCW it will be difficult to avoid some
interference problems, however.

Cheers, Jim Moritz
73 de M0BMU

-----Original Message-----
From: owner-rsgb_lf_group@blacksheep.org
[mailto:owner-rsgb_lf_group@blacksheep.org] On Behalf Of Gary - G4WGT
Sent: 22 June 2005 13:49
To: rsgb_lf_group@blacksheep.org
Subject: LF: RE: Rugby Loran QRV

...I compared noise levels with previous Spec Lab captures & I am also
reading about a 10db or more increase across 136 KHz using on the spectrum
graph on Spec Lab. The waterfall display is showing strong LORAN lines all
across the display, considering this is at mid-day is it going to be worse
at night in darkness? if this is the case it will be useless for me. With
the G3LNP loop connected straight to the Yaesu FT-747 & the loop tuned to
the 136 KHz band the signal strength on the S-Meter has increased from S4 to
S9...