Dear John, LF Group,
Well I would certainly try to work you - for a UK - only band, you are
probably the ultimate in DX!
QSOs over your kind of distance seems to be more difficult on 500k than
136k, partly because of the lower ERP limit, partly because of the more
variable propagation at this distance. I think CW is the prefered mode on
500k at the moment because it is familiar and most stations can work each
other within mainland UK once they have TX and antenna sorted out. Most of
the QSOs are fairly routine and don't get mentioned on the reflector. The
QRSS beacons from DL and SM are quite well received here, so probably
feasible for a longer distance QSO if CW fails. Several stations have QRSS
capability, which is pretty simple to set up and use if you have a PC and a
CW TX.
For the TX antenna, I would go for the long wire - height is the most
important thing as Alan says, but if you have a reasonable length of wire it
makes it easier to match the antenna and reduces losses. The trees seem to
be one of the main things that reduce antenna efficiency, so at least you
won't have that problem! The grounding is not too critical most of the time;
I have found that a number of ground rods connected together is as good as
anything, but that might be different if your ground is mostly rock.
A simple way of boosting sensitivity with a loop antenna is to make the loop
bigger - 1m diameter is a bit small for weak signal reception without a
low-noise preamp. It is easy to make a fixed wire loop of several m^2 aimed
in the general direction of interest - see
http://www.wireless.org.uk/lazy.htm - which was intended for 136kHz, but
will also work with a reduction in tuning inductance at 500k, provided the
coax is not too long.
Navtex is still on 518kHz (and 490kHz) - maybe it is just me, but there seem
to be fewer broadcasts than there used to be... still, you should not have
to wait long for a broadcast to appear on 518k at least.
Good luck - hope you get QRV soon!
Cheers, Jim Moritz
73 de M0BMU
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