Alignment of (Narrow Band) DATA and
WSPR frequency’s on the 500
KHz band.
The original wspr frequency
502.4 was
defined as the
working frequency to
utilise the ‘clean’ area just
under the 504 harmonic, whilst avoiding
the various beacons
running across the
501/504 band at the time.
However, time has moved on and there are now numerous ‘dial setting’s’ in use
both sides of the Atlantic.
Due
to an apparent increase
in the side band
noise from the 504 signal ,
possibly by enhanced propagation ,
the ROS MF (100 hz b/w)
working frequency is to be re defined
as 500 USB dial set
giving a centre
carrier frequency of 501.500
Due to Ae
bandwidth and perhaps
alignment with
other band’s,
I would suggest
the original WSPR 502.4K is
replaced with the lower frequency
of 495.9K , thus
restoring the System’s coverage
and facilitating changes
of mode etc within a narrow bandwidth.
I don’t
see this
detracting from the monitoring of
spot frequency beacons
over 505Khz , but more appropriate
to transmitting stations ,
which by the nature of the
antenna arrays are not
able comfortably to
qsy from top
to bottom of the band
without re-tuning, not always a simple
option.
Comments or suggestions
please ?.
Graham
G0NBD