Jim posed some possible flaws in alternative ways of generating BPSK in
terms of bandwidth.
I think we must work out what is an acceptable bandwidth for LF
transcontinental working (or indeed any other distance or path).
We must not be trapped into thinking that bandwidths close to those used for
QRSS are essential. They may be convenient - even efficient - but if there is
room on the band for people to use CW for intra-Europe working, why be
forced into anything less for inter-continental? This means 30dB bandwidths in
the region of 100Hz and 60dB bandwidths of, say 500Hz. In practice, there
are very few people close enough to each other for a signal 60dB down to be
audible at all.
Plainly there must be enough space to accommodate a group of people trying
to work across the Atlantic, but this is a bandplanning issue not a technical
one.
In short, if it is acceptable for me to use CW to work VE, it should be
acceptable for BPSK to have the same practical bandwidth.
I bet that will start a battle!!!
Mike, G3XDV (IO91VT)
http://www.lf.thersgb.net
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