jawod wrote:
. . .
Seems to me, that Joules per unit time is precisely the measure that's
needed in this "analysis". Is this Voltage, or am I mistaken?

Joules (energy) per unit time is power, not voltage.

Compare the density of the dust cloud with the charge collected. There
should be a correlation. What about velocity of the cloud: more charges
transferred per unit time.

Charge per unit time is current.

If your rug was scorched, some "work" was done. My college physiscs is
only a nightmare away: what is the relation of Joules to work?

The joule is a unit of energy. Work is energy, so it can also be
expressed in joules.

. . .
If a given volume of dust particles moves through the field of an
antenna (it would have a field, wouldn't it? ... even if grounded?

An antenna creates an electrostatic field if charged, but an
electromagnetic field only if that charge is being accelerated, that is,
if it carries current which changes with time.

perhaps field is the wrong word), increasing velocity of the volume
would mean more particles per unit time passing the antenna. Hence more
charge transferred: more charge per unit time. Again, is this Voltage?

No, charge per unit time is current.

. . .

It's impossible to contribute much to the understanding of complex
phenomena without first gaining an understanding of the most basic
principles.

Roy Lewallen, W7EL

Tom Donaly wrote:
Whether it's dust, snow, or the atmospheric electric field charging the
antenna, the noise is still corona discharge. At least that's what most
of the sources say.

It is my understanding that the air around a conductor must
ionize for it to be defined as corona. Obviously, there is
a time when charge is transferred to the antenna before
ionization (corona) occurs. Corona is defined as a discharge
function. The charging function must necessarily occur before
corona. If the charge is not allowed to accumulate up to the
ionization level, corona will not occur, by definition.
Precipitation static occurs before the corona threshold is
reached. For what it's worth, here's what the 2000 ARRL
Handbook says:

"Precipitation Static and Corona Discharge"

"Precipitation static is an almost continuous hash-type noise
that often accompanies various kinds of precipitation, including
snowfall. Precipitation static is caused by rain drops, snowflakes
or even *wind-blown dust*, transferring a small electrical charge
on contact with an antenna."

"Electrical fields under thunderstorms are sufficient to place
many objects such as trees, hair and antennas, into corona
discharge."

Although not stated explicitly, seems to me there is a strong
implication that precipitation static is not strong enough to
ionize the air, i.e. not strong enough to cause corona to exist.
Indeed, the arcing at a coax connector or the DC grounding of
an antenna may be enough to prevent ionization and corona
during a precipitation static episode.
--
73, Cecil http://www.qsl.net/w5dxp

jawod wrote:
Cecil Moore wrote:

Tom Donaly wrote:

Whether it's dust, snow, or the atmospheric electric field charging
the antenna, the noise is still corona discharge. At least that's
what most
of the sources say.



The argument is not what it is called. The argument is whether
charged dry-air dust particles can transfer charge to bare-wire
antennas.

Man, you guys really crack me up. I must admit I kinda enjoy reading
your posts, though.

\There must be some source citing experimental evidence of charged
particles in a dust storm transferring their charges to a collector of
some sort (antenna). I alluded earlier to a practical use of such
collection...
Cecil, you said you have no idea how many Joules were represented (or
something along those lines).

Seems to me, that Joules per unit time is precisely the measure that's
needed in this "analysis". Is this Voltage, or am I mistaken?

Compare the density of the dust cloud with the charge collected. There
should be a correlation. What about velocity of the cloud: more charges
transferred per unit time.

If your rug was scorched, some "work" was done. My college physiscs is
only a nightmare away: what is the relation of Joules to work?

What was the other issue: number of particles versus the charge per
particle? Got me.

As the particles are swept off the surface of the desert, would their
charge (per particle) be distributed (as Gauss or some other )?

I would think the # particles would be more important.

If a given volume of dust particles moves through the field of an
antenna (it would have a field, wouldn't it? ... even if grounded?
perhaps field is the wrong word), increasing velocity of the volume
would mean more particles per unit time passing the antenna. Hence more
charge transferred: more charge per unit time. Again, is this Voltage?

I guess I can't part with my trickle charger idea.

You guys have at it. Thanks for letting me butt in.

John

There was once an article in the old Scientific American Amateur
Scientist section about using the earth's electric field to
power various static electric motors. Just build a motor from
one of the simple designs on the web; using a weather balloon,
run a wire up 300 feet or so (should give you 9000 volts or
so on a clear day); attach your motor between the wire and ground, and,
once the wire charges up, the motor turns. You won't get much work
out of it, but it'll run a long time.
73,
Tom Donaly, KA6RUH

Cecil Moore wrote:

Tom Donaly wrote:

Whether it's dust, snow, or the atmospheric electric field charging
the antenna, the noise is still corona discharge. At least that's what
most
of the sources say.


It is my understanding that the air around a conductor must
ionize for it to be defined as corona. Obviously, there is
a time when charge is transferred to the antenna before
ionization (corona) occurs. Corona is defined as a discharge
function. The charging function must necessarily occur before
corona. If the charge is not allowed to accumulate up to the
ionization level, corona will not occur, by definition.
Precipitation static occurs before the corona threshold is
reached. For what it's worth, here's what the 2000 ARRL
Handbook says:

"Precipitation Static and Corona Discharge"

"Precipitation static is an almost continuous hash-type noise
that often accompanies various kinds of precipitation, including
snowfall. Precipitation static is caused by rain drops, snowflakes
or even *wind-blown dust*, transferring a small electrical charge
on contact with an antenna."

"Electrical fields under thunderstorms are sufficient to place
many objects such as trees, hair and antennas, into corona
discharge."

Although not stated explicitly, seems to me there is a strong
implication that precipitation static is not strong enough to
ionize the air, i.e. not strong enough to cause corona to exist.
Indeed, the arcing at a coax connector or the DC grounding of
an antenna may be enough to prevent ionization and corona
during a precipitation static episode.

Cecil, you can do a web search for "precipitation static," and
"Saint Elmo's fire," to find out what most people think
precipitation static is. Before I'd believe that each little
raindrop makes a noise as it strikes the antenna, I'd want to
see an experiment showing this. Most of the sources on the
web, at least, don't mention it, but generally agree with
Tom about the cause of the problem. You can read all that
for yourself.
73,
Tom Donaly, KA6RUH

Tom Donaly wrote:
Cecil, you can do a web search for "precipitation static," and
"Saint Elmo's fire," to find out what most people think
precipitation static is. Before I'd believe that each little
raindrop makes a noise as it strikes the antenna, I'd want to
see an experiment showing this.

It's only raindrops having a charge different from
the antenna that make the noise and I have previously
explained the mechanism of charge equalization between
the two dipole elements through the link.

Seems to me only magical thinking would result in each
and every raindrop having a charge exactly equal to the
antenna upon which it is falling. I'd like to see you
come up with a proof for such an assertion.

Most of the sources on the
web, at least, don't mention it, but generally agree with
Tom about the cause of the problem. You can read all that
for yourself.

I have read it for myself and *nothing* I have read agrees
with W8JI. Corona doesn't exist until ionization takes
place. Precipitation static and even arcing do not require
any corona to exist. Here's a web page that explains the
difference between arcing and corona discharge including
a gray area called "brush discharges".

http://www.ce-mag.com/archive/1999/novdec/mrstatic.html

Please notice that arcing at a coax connector doesn't require
corona at all.
--
73, Cecil, http://www.qsl.net/w5dxp

Cecil Moore wrote:
Tom Donaly wrote:

Cecil, you can do a web search for "precipitation static," and
"Saint Elmo's fire," to find out what most people think
precipitation static is. Before I'd believe that each little
raindrop makes a noise as it strikes the antenna, I'd want to
see an experiment showing this.


It's only raindrops having a charge different from
the antenna that make the noise and I have previously
explained the mechanism of charge equalization between
the two dipole elements through the link.

Seems to me only magical thinking would result in each
and every raindrop having a charge exactly equal to the
antenna upon which it is falling. I'd like to see you
come up with a proof for such an assertion.

Most of the sources on the
web, at least, don't mention it, but generally agree with
Tom about the cause of the problem. You can read all that
for yourself.


I have read it for myself and *nothing* I have read agrees
with W8JI. Corona doesn't exist until ionization takes
place. Precipitation static and even arcing do not require
any corona to exist. Here's a web page that explains the
difference between arcing and corona discharge including
a gray area called "brush discharges".

http://www.ce-mag.com/archive/1999/novdec/mrstatic.html

Please notice that arcing at a coax connector doesn't require
corona at all.

Cecil,
show me your experiments. You can ratiocinate your head
off and you still won't be any closer to the truth. Tell me how I
can spray water drops on my antenna and make a noise in my
receiver as each drop hits the antenna. Can you do it?
73,
Tom Donaly, KA6RUH

On Thu, 15 Jun 2006 17:42:40 GMT, "Tom Donaly"
wrote:

You can ratiocinate your head
off and you still won't be any closer to the truth.

Hi Tom,

As Judge Judy would say, "Don't discharge on my leg and tell me its
corona even if you've been drinking beer."

73's
Richard Clark, KB7QHC

Tom Donaly wrote:
show me your experiments. You can ratiocinate your head
off and you still won't be any closer to the truth. Tell me how I
can spray water drops on my antenna and make a noise in my
receiver as each drop hits the antenna. Can you do it?

No, I think it is up to you to prove that each and every
raindrop that falls has exactly the same charge as
any antenna upon which it might fall. Which means that
you must prove that all antennas being rained upon have
identical unchanging charges. That is what would have to
be true for you to be correct. Sorry Tom, please peddle
your magical thinking to someone else. What do you think
about the 2000 ARRL Handbook quote?

"Precipitation static is an almost continuous hash-type noise
that often accompanies various kinds of precipitation, including
snowfall. Precipitation static is caused by rain drops, snowflakes
or even wind-blown dust, transferring a small electrical charge
on contact with an antenna."

The physics of charged particles has been understood for
a century or so. I am not going to waste my time proving
those known and accepted facts of physics. It is up to you
and W8JI to prove a century of physics knowledge to be
wrong. Good luck on proving that all static is caused by
corona discharge even in the absence of the necessary
ionization that defines the word "corona".
--
73, Cecil, http://www.qsl.net/w5dxp

Richard Clark wrote:
On Thu, 15 Jun 2006 17:42:40 GMT, "Tom Donaly"
wrote:


You can ratiocinate your head
off and you still won't be any closer to the truth.


Hi Tom,

As Judge Judy would say, "Don't discharge on my leg and tell me its
corona even if you've been drinking beer."

73's
Richard Clark, KB7QHC

In Cecil's case he'd claim it was Corona Extra.
73,
Tom Donaly, KA6RUH

Cecil Moore wrote:

Tom Donaly wrote:

show me your experiments. You can ratiocinate your head
off and you still won't be any closer to the truth. Tell me how I
can spray water drops on my antenna and make a noise in my
receiver as each drop hits the antenna. Can you do it?


No, I think it is up to you to prove that each and every
raindrop that falls has exactly the same charge as
any antenna upon which it might fall. Which means that
you must prove that all antennas being rained upon have
identical unchanging charges. That is what would have to
be true for you to be correct. Sorry Tom, please peddle
your magical thinking to someone else. What do you think
about the 2000 ARRL Handbook quote?

"Precipitation static is an almost continuous hash-type noise
that often accompanies various kinds of precipitation, including
snowfall. Precipitation static is caused by rain drops, snowflakes
or even wind-blown dust, transferring a small electrical charge
on contact with an antenna."

The physics of charged particles has been understood for
a century or so. I am not going to waste my time proving
those known and accepted facts of physics. It is up to you
and W8JI to prove a century of physics knowledge to be
wrong. Good luck on proving that all static is caused by
corona discharge even in the absence of the necessary
ionization that defines the word "corona".

You're the one who made the statements, Cecil, so you're the one
who has to prove them. Just tell me how you sprayed charged
water drops on your antenna and recorded the noise from your
receiver when each one of them hit. If you can't do that, all
appeals to a higher authority are meaningless.
73,
Tom Donaly, KA6RUH