Jim, Andy, LF Group,
I am not in the position to put in anything re transmitting on 500kHz myself
but I would like to stronly support the position of Jim M0MBU. 
WSPR is a vy interesting mode and its advantages of having an "automatic"
background in logging and distributing the reception results is really
fascinating. 
And as John, F5VLF had put it just recently and as he urged us (the
amateurs) to keep on experimenting: "...To cite just two examples of this
ingenuity (the ham's): transmitting loops seem to have been almost unknown
to the old-time professionals, and some of the low data rate systems we have
been experimenting with would have been impracticable then. ...". 
We have different modes now and different means to detect weak signals and
WSPR is definitely one mode in this group with new advantages!
We are neither ships (exception DI2AM) nor do we have powerful transmitters
with huge antennas beside the sea (maybe you guys in G-land have it and we
just don't know it, hi!), so we still have a lot to find out.
I am very greatful for all amateurs who make great personal efforts to
provide beacons for the rest of us!
73
de
Klaus
DJ6LB
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