From: Henry T. Rand Jr. (rrand@PICA.ARMY.MIL)
I have made many QRP contacts over 8000-9000 mile paths to places like ZL,
VK and YB. Some of these have been done with milliwatt power and some
with milliwatt power in my pre-tower/KT34XA days. It is not all that
difficult to do when propagation conditions are favorable.
There were a few instances where I heard my own signal as an echo. I remember
hearing this a few times on 15 and 12 meters. It was confusing the first time
as I though someone else was on frequency (I was using full break-in on CW)
but every time I stopped sending to listen the signal stopped. It wasn't too
hard to figure out it was an echo. I just sent single dits at high speed and
listened. Time delay was a small fraction of a second. I never attempted ot
to measure it. So, it is possible for a signal to propagate completely
around the world and be heard by the originating station. What is amazing
though is that it could happen with 4 watts and a dipole.
These long distance paths are where a beam really starts to make a difference.
Reducing the number of hops with a lower takeoff angle lowers the absorption
and allows the QRPer to be heard better or just heard at all. Height of the
beam also has a great effect. When I put up the tower and the XA, I noticed
immediately great improvements over my roof mounted(4 ft above) A3 triband
yagi. Under the right conditions though even a wire will get you through.
You just have to wait for them.
Randy Rand AA2U
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