Dear Graham, Gus, LF Group,
Since SM6BHZ can use 503.8 - 504.0kHz, and also Rik ON7YD and other ON
stations (not sure about this mode, though), it would seem to make sense to
use this as the default European WSPR frequency range. I think the other Eu
beacon stations are restricted to using spot frequencies.
I also have received some enquiries from Fritz Raab, W1FR, who is
coordinating the US 500k band plan for their recently extended band,
regarding having a common agreed WSPR beacon segment, which would certainly
make good sense. The proposed US band plan looks like this:
495.0 - 495.1 QRSS, 1-Hz spacing, 40 stations
495.1 - 495.6 CW/PSK beacons midwest, 100-Hz spacing, 10 stations
495.6 - 499.0 Comms
497.5 Calling frequency
499.0 - 501.0 Reserved for heritage stations and special events
501.0 - 501.2 WSPR
501.2 - 505.0 Comms
505.0 - 505.2 DX window
505.2 - 508.5 Comms
507.5 Calling frequency
508.5 - 510.0 CW/PSK beacons east, south, west, Pacific, 50-Hz spacing, 30
stations
510.0 - 511.0 WE2XGR beacons
511.0 - 515.0 WE2XGR SSB and wideband modes
Quoting from W1FR's email:
"...
(a) 501.0-501.2: Conveniently on one side of our comms
band. Will not overload WSPR receivers near 504 kHz.
Apparently in EU CW-beacon band.
(b) 503.8-504.0: Apparently same as what you guys are
using. Cuts our comms band in the middle. Nearby
stations may overload US receivers trying to hear EUs.
(c) 503.9-504.1: Same problems as above with cutting
comms band in two and overloading. Conveniently
straddles both G/ON/EI and Canadian bands.
..."
Although it is possible to operate WSPR with split TX/RX frequencies, this
has the drawback that, without 2 receivers, you can only receive stations
from one side of the pond during one session. This is a drawback for
receiving stations outside western Europe and the US, and for gathering
propagation data from WSPR. There is some argument that it could be
difficult to receive DX signals in the presence of strong local beacons in
the same frequency range, but I think this is less of a problem on 500k WSPR
due to the relatively weak ground-wave signals and the randomised time
slots, compared to the experience with 136kHz QRSS beacons. I suppose the
main reason for sticking with 503.8 - 504.0kHz is that it has become the
default for UK stations, and that the band below 503.0kHz has been mostly
used for CW. On the other hand, a significant number of stations experience
QRM near to 504.0kHz, attributed to the 2nd harmonic of Atlantic 252,
although that may not be the only source. So a beacon segment near the lower
band edge in line with the US intention could actually give better results.
What do other people think?...
Cheers, Jim Moritz
73 de M0BMU
...
Graham,
for me there is no problem to tramsmit under 504 kHz.
Why not run WSPR beacon from 503.900- 504.000 kHz !?
de Gus SM6BHZ
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