folded dipoles
"chuck" wrote in message
...
Dave wrote:
the noise is caused by corona on the antenna due to the electric field
between the ground and cloud. this field can be many thousands of kv per
meter which is enough to cause sharp points and tips of elements to
generate corona which makes the hiss and pop noises.
Hi Dave,
Yeah, that's another hypothesis. One might even be led to reason that
insulation would prevent these corona discharges. Yet, it is quite easy to
charge a grounded antenna (completely insulated) with the electric field
that exists between the ground and clouds (or air masses).
So we have at least two candidate causes for what is called by some
"precipitation static": charged particles physically impinging on the
antenna wire; and electrostatically induced charges that produce corona
discharges. Are there others? Can both processes occur simultaneously? Are
the two processes simply different paths to the same end: corona
discharges?
Do we have a way to test these competing hypotheses?
the easiest test is done for us, all we have to do is observe.
'precipitation' static can occur without rain or snow, and it sounds exactly
like the noise when there is rain or snow... so i say the corona effect is
the major cause and any effect from charged particles is secondary and much
smaller.
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