> 160 meters is different from other bands in some
> respects and it might be interesting to play around with it. For one
> thing, groundwave is excellent, better than any other band, I believe.
> Jim is about 100 miles from me and even running low power he was 20 to
> 30 over S9.
>From a technical perspective 160 meters poses significant issues
for skywave RTTY. In particular, multipath and differential
fading are much worse than even on 80 meters (and they are already
problem there).
If one were going to attempt serious work on 160 as opposed to
simply cluttering the band with another high power local signal,
it would be far better to use 23 (22.725) Hz shift FSK. PSK31 or
a slower PSK31 -like mode that was far less effected by multipath
and selective fading.
Emission modes with high baud rates, multiple tones and/or
wide shifts (a wide spread between lowest and highest tone)
are not well suited for lower frequencies. Although it is
another couple orders of magnitude lower in frequency, the
military has even resorted to on/off keyed RTTY in the LF
spectrum (60 - 200 KHz) at very slow speeds due to the technical
limitations.
73,
... Joe, W4TV
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