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Old February 4th 05, 03:48 AM
ShortwaveMan
 
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I found one bit you can read about reversal of earth's magnetic field:
http://uplink.space.com/showflat.php...ro&Number=2107


~~~~~ God gives peace not war +
"ShortwaveMan" wrote in message
ink.net...
It is a scientific fact recently discovered, that the earth's magnetic
field is steadilly weakening. They think it is because the polarity of the
field is changing: they call it a "reversal". Be that as it may, it is my
feeling that it is real and causing shortwave reception to degrade because
the ionosphere is affected by the magnetic field.

I used to think that the magnetic field was quite uniform, unmoving and
static but scientists have found that is not the case at all. Bottom line
is that charged particles react to magnetic fields. The reflective layer
is a layer of particles of the atmosphere that results from solar
radiation of many forms stripping electrons off the particles.

Think of the layer of charged particles as a mirror. If the mirror is in a
quiet stream, light reflecting off the mirror will be uniform. If the
stream is ruffled or full of eddies and the bottom is full of rocks, the
light will be disturbed by the stream and not uniform at all. If the light
in the analogy is the radio energy (radio waves if you like), then any
ruffling or movement in the layer is going to ruffle the signal too, so it
may fade in and out or be fluttery or full of static and so on. If the
magnetic field of the earth is moving and changing a lot in different ways
in different places, a lot of radio energy is either being lost into space
or absorbed. It is a bit like two people holding a big sheet of aluminum
foil between them and moving it around in the sun. If the foil is held
still, the stream of reflected light is quiet and steady, but if the foil
is moving around in a stiff wind, the light will go all over the place,
not necessarilly into the viewer's eyes.

This may be just temporary, or it may be a long term effect, but one thing
is certain, the environment in which we live is affected by physical
forces in continual flux. If the "reversal" occurs in our lifetime, it may
get very interesting. The same magnetic field on which we have come to
rely for communications also protects the planet from harmful radiation
such as x-rays and ultraviolet light. That means if the field diminishes
or disappears, so will our protection from radiation. You can find a lot
on the internet about the subject of pole reversals if you want to study
the subject.

~~~~~ God gives peace not war +
wrote in message
oups.com...


Found a link to a picture..describes Propagation by frequecy; etc..


http://www.ips.gov.au/Main.php?CatID...ospheric%20Map

- My question is:
WHY has propagation been so Fu*k*d up.. during the last year?? ??