Dear Martin and Group,
Most of the Loran noise seems to come from Lessay on the
French coast, which is much nearer SE England than Wales, so
one would expect the Loran noise to be relatively weak at your
QTH. At my QTH (Hertfordshire), Loran is often the limiting factor
on receive sensitivity when QRM/QRN is low. If Loran is not a
factor, you should be able to hear a crackle of QRN, especially
after dark. Perhaps the other GW stations could tell you what to
expect.
A possible reason you are experiencing general lack of sensitivity
might be receiver front-end overload. Most RXs just have a low-
pass front end filter for the LF/MF range, and the non-resonant
antenna means your RX is being bombarded with LF and MF
broadcast signals, and powerful LF commercial stations, all of
which will be vastly stronger than tiny amateur signals, which
consequently will get buried by assorted intermods, blocking, etc. If
this is the case, tuning the antenna (as described by G4GVC in the
LF handbook), or using a preselector, (G3YXM's design, for
example) might improve the situation greatly.
Cheers, Jim Moritz
73 de M0BMU
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