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Old March 8th 15, 12:17 AM posted to rec.radio.amateur.antenna
[email protected] nm5k@wt.net is offline
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First recorded activity by RadioBanter: Jul 2006
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Default E/M radiation from a short vertical aerial

On Friday, March 6, 2015 at 7:31:12 PM UTC-6, Jerry Stuckle wrote:

That depends entirely on the radiation pattern of the antenna. For
instance, the sky wave will be that part of the pattern which has fairly
high angle of radiation (but lower than the space wave), and the surface
wave will have a very low angle of radiation.


The space wave will be quite low angle if working from one point
on the earth to another point on the earth. Strictly speaking, a
space wave could be at any angle, if you include talking from the
earth to someone in space. Earth to ISS is space wave.
The signals one receives from a local VHF/UHF FM radio or TV station
are space wave. Two CB'ers talking to each other 5 miles apart are
using space wave. Only in the case of the earth dweller talking to
someone in space, or on the moon, etc would be using a space wave
at a higher angle than the usual angle needed for sky wave.

And on the high HF bands like 10m, in some cases the angles used
for skywave can be fairly low if working DX.
But those angles would still likely be a bit higher than terrestrial
earth to earth space wave communication.

True ground wave, which to me, is the same as the surface wave,
actually can follow the curvature of the earth, which a space wave
cannot do. But true ground or surface waves are generally only
taken advantage of on the lower frequencies such as MW, or LW.

But they can be used likely as high as say the 40m band in some
cases. I used to have a fairly stout ground wave on 40m when I
ran a high ground plane. And I think part of that energy was acting
as a surface wave and following the curvature of the earth.
The reason I think so, is because the distances I could work with it
were a good bit farther than what I would expect with the space wave
alone.
And I could use the space and surface wave in that case, no matter
what time of day or night, or regardless of the conditions needed for
sky wave between the two locations. So lots of times during the day
when the MUF dropped low enough to lose those people who were 100-150
miles away via sky wave, I was still able to work them via the ground
wave. The people using the dipoles and such could hardly hear a peep
out of the ones I was working in those cases.


And BTW - don't worry about the trolls who have no idea what they are
talking about - but insist on showing their ignorance, anyway.


We sure wouldn't want to have any of that, now would we.. :/