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W5DXP June 21st 12 03:55 AM

loop antennas and noise suppresion
 
On Wednesday, June 20, 2012 12:05:07 PM UTC-5, Boomer wrote:
This is an attractive specification, but comes with a
serious performance cost.


A G5RV is a good performer on 75m, 40m, 20m, and 12m. Here's why on 75m and 40m.

http://www.w5dxp.com/G5RV.HTM
--
73, Cecil, w5dxp.com

Sal M. O'Nella[_2_] June 22nd 12 04:02 AM

loop antennas and noise suppresion
 

"W5DXP" wrote in message
...
On Wednesday, June 20, 2012 3:40:40 PM UTC-5, Sal M. O'Nella wrote:
I have no idea how to ground a dipole and I don't think I've ever done it
except by accident.


Apparently, you have never had P-static problems with your dipoles. I,
however, had a coax connector start arcing in the middle of the night and
it sounded like a machine gun.
--
73, Cecil, w5dxp.com


Nonsuch, Cecil, unless it's been an off-again-on-again
problem that I simply never appreciated for its affect on
my QSOs.

With Field Day coming and my being the Field Day Chairman
for the local club (www.sobars.org), as well as our President,
any diddling with my home QTH dipoles must wait.

I am taking an unproven design for a 20m Cubical quad to FD.
By EZNEC, it looks good but it wants a 75-ohm feed, which I am
prepared to provide. I have a choked cable ready to go.

In your opinion, is there a ground required? At the antenna or at
my van? Both? I own some ground rods and a sledgehammer.

(Last year, I used a 20m dipole at 30 feet, operating out of my van.
Everything floated above ground without incident and many QSOs.)

I value your opiniion.

73
"Sal"
(really KD6VKW)



Szczepan Bialek June 22nd 12 04:20 PM

loop antennas and noise suppresion
 

"Sal M. O'Nella" napisał w wiadomości
...


(Last year, I used a 20m dipole at 30 feet, operating out of my van.
Everything floated above ground without incident and many QSOs.)

I value your opiniion.


In Marconi opinion:
http://www.nobelprize.org/nobel_priz...ni-lecture.pdf

"By "connected to earth" I do not necessarily mean an ordinary metallic
connection as used for ordinary wire telegraphs.
The earth wire may have a condenser in series with it, or it may be
connected to what is really equivalent, a capacity area placed close to the
surface
of the ground (Fig. 4).
It is now perfectly well known that a condenser, if large enough, does not
prevent the passage of high frequency oscillations, and therefore in these
cases
the earth is for all practical purposes connected to the antennae."


And Wiki:
"The use of the term ground (or earth) is so common in electrical and
electronics applications that circuits in portable electronic devices such
as cell phones and media players as well as circuits in vehicles such as
ships, aircraft, and spacecraft may be spoken of as having a "ground"
connection without any actual connection to the Earth. This is usually a
large conductor attached to one side of the power supply (such as the
"ground plane" on a printed circuit board) which serves as the common return
path for current from many different components in the circuit." From:
http://en.wikipedia.org/wiki/Ground_(electricity)
S*





[email protected] June 22nd 12 05:15 PM

loop antennas and noise suppresion
 
Szczepan Bialek wrote:

"Sal M. O'Nella" napisa? w wiadomo?ci
...


(Last year, I used a 20m dipole at 30 feet, operating out of my van.
Everything floated above ground without incident and many QSOs.)

I value your opiniion.


In Marconi opinion:


Marconi was wrong, idiot.

And the topic of discussion is prevention of static build up on antennas
which requires a particular set of circumstances to occur and does NOT
happen all the time and everywhere.

You are an idiot.





Ian[_5_] June 22nd 12 06:51 PM

loop antennas and noise suppresion
 
"Szczepan Bialek" wrote in message
...

"Sal M. O'Nella" napisał w wiadomości
...


(Last year, I used a 20m dipole at 30 feet, operating out of my van.
Everything floated above ground without incident and many QSOs.)

I value your opiniion.


In Marconi opinion:
http://www.nobelprize.org/nobel_priz...ni-lecture.pdf

"By "connected to earth" I do not necessarily mean an ordinary metallic
connection as used for ordinary wire telegraphs.
The earth wire may have a condenser in series with it, or it may be
connected to what is really equivalent, a capacity area placed close to
the
surface
of the ground (Fig. 4).
It is now perfectly well known that a condenser, if large enough, does not
prevent the passage of high frequency oscillations, and therefore in these
cases
the earth is for all practical purposes connected to the antennae."


And Wiki:
"The use of the term ground (or earth) is so common in electrical and
electronics applications that circuits in portable electronic devices such
as cell phones and media players as well as circuits in vehicles such as
ships, aircraft, and spacecraft may be spoken of as having a "ground"
connection without any actual connection to the Earth. This is usually a
large conductor attached to one side of the power supply (such as the
"ground plane" on a printed circuit board) which serves as the common
return
path for current from many different components in the circuit." From:
http://en.wikipedia.org/wiki/Ground_(electricity)
S*


What is your point is (other than demonstrating copy-and-paste)? If it is
that "all aerials require an earth" then you're clearly ignoring previous
postings which have said that this is not the case.
The Wiki item doesn't seem to appreciate the difference between a return
path on a circuit board and a connection to earth.

Regards, Ian.




tom June 23rd 12 01:54 AM

loop antennas and noise suppresion
 
On 6/22/2012 10:20 AM, Szczepan Bialek wrote:
"Sal M. napisał w wiadomości
...


(Last year, I used a 20m dipole at 30 feet, operating out of my van.
Everything floated above ground without incident and many QSOs.)

I value your opiniion.


In Marconi opinion:
http://www.nobelprize.org/nobel_priz...ni-lecture.pdf

"By "connected to earth" I do not necessarily mean an ordinary metallic
connection as used for ordinary wire telegraphs.
The earth wire may have a condenser in series with it, or it may be
connected to what is really equivalent, a capacity area placed close to the
surface
of the ground (Fig. 4).
It is now perfectly well known that a condenser, if large enough, does not
prevent the passage of high frequency oscillations, and therefore in these
cases
the earth is for all practical purposes connected to the antennae."


And Wiki:
"The use of the term ground (or earth) is so common in electrical and
electronics applications that circuits in portable electronic devices such
as cell phones and media players as well as circuits in vehicles such as
ships, aircraft, and spacecraft may be spoken of as having a "ground"
connection without any actual connection to the Earth. This is usually a
large conductor attached to one side of the power supply (such as the
"ground plane" on a printed circuit board) which serves as the common return
path for current from many different components in the circuit." From:
http://en.wikipedia.org/wiki/Ground_(electricity)
S*


And he changes his argument again. Because now the electrons cannot
flow to ground. Which blows his whole "antennas radiate electrons"
argument.

Troll or moron? You decide.

tom
K0TAR



Szczepan Bialek June 23rd 12 04:07 PM

loop antennas and noise suppresion
 

"tom" napisal w wiadomosci
. net...
On 6/22/2012 10:20 AM, Szczepan Bialek wrote:
"Sal M. napisał w wiadomości
...


(Last year, I used a 20m dipole at 30 feet, operating out of my van.
Everything floated above ground without incident and many QSOs.)

I value your opiniion.


In Marconi opinion:
http://www.nobelprize.org/nobel_priz...ni-lecture.pdf

"By "connected to earth" I do not necessarily mean an ordinary metallic
connection as used for ordinary wire telegraphs.
The earth wire may have a condenser in series with it, or it may be
connected to what is really equivalent, a capacity area placed close to
the
surface
of the ground (Fig. 4).
It is now perfectly well known that a condenser, if large enough, does
not
prevent the passage of high frequency oscillations, and therefore in
these
cases
the earth is for all practical purposes connected to the antennae."


And Wiki:
"The use of the term ground (or earth) is so common in electrical and
electronics applications that circuits in portable electronic devices
such
as cell phones and media players as well as circuits in vehicles such as
ships, aircraft, and spacecraft may be spoken of as having a "ground"
connection without any actual connection to the Earth. This is usually a
large conductor attached to one side of the power supply (such as the
"ground plane" on a printed circuit board) which serves as the common
return
path for current from many different components in the circuit." From:
http://en.wikipedia.org/wiki/Ground_(electricity)
S*


And he changes his argument again. Because now the electrons cannot flow
to ground. Which blows his whole "antennas radiate electrons" argument.


All time the electrons flow to or from the ground.
"Let me answer some of your questions. Capacitors loose their charge both
through the insulation between the plates and through the air surrounding
the capacitor. The charge is a surplus of electrons on one plate and a
rarefaction of electrons on the other. Where the electrons are compacted
(the negative plate) the electrons tend to push each other off. Where there
is a deficit of electrons (the positive plate) electrons are attracted from
other sources - air, the positive plate. Both of these actions tend to
decrease the potential difference between the plates... to discharge the
capacitor. From: http://www.newton.dep.anl.gov/askasc...0/phy00900.htm


Troll or moron? You decide.


" Variable capacitors with their plates open to the atmosphere were commonly
used in radio tuning circuits."
If you have such try to measure "the Capacitor charge holding" and decide.
S*



Ian[_5_] June 23rd 12 04:27 PM

loop antennas and noise suppresion
 
"Szczepan Bialek" wrote in message
.. .

All time the electrons flow to or from the ground.
"Let me answer some of your questions. Capacitors loose their charge both
through the insulation between the plates and through the air surrounding
the capacitor. The charge is a surplus of electrons on one plate and a
rarefaction of electrons on the other. Where the electrons are compacted
(the negative plate) the electrons tend to push each other off. Where
there is a deficit of electrons (the positive plate) electrons are
attracted from other sources - air, the positive plate. Both of these
actions tend to decrease the potential difference between the plates... to
discharge the capacitor. From:
http://www.newton.dep.anl.gov/askasc...0/phy00900.htm

S*

Let's disregard the spelling error ("loose" and "lose").
The article continues thus:

"How can this be discouraged? There are a number of possibilities, but they
are selectively employed due to practical and economic reasons. Two possible
methods - Increase the distance between the plates or change the material
separating the plates. For instance glass insulators are sometimes used on
very large (tall as a house) capacitors or the capacitor may be packed in
oil. "

Anyone seen a capacitor that is as big as a house?

snip

"Often one wants a capacitor to have the largest possible capacitance. This
is accomplished by making the plates large in area and close together and
filling the space between the plates with an insulator which has a large
dielectric constant. A parallel plate capacitor has a capacitance given by C
= eA/d, where e is the dielectric constant, A is the area of the plates and
d is the separation between the plates. Notice that making the area large
and the separation small makes it easier for a current to flow between the
plates, thereby discharging them. For many purposes the small leakage
current is not a serious problem. Often a large value of capacitance is much
more important than a slow discharge. Notice that even with air between the
plates, cosmic rays will occasionally pass through the capacitor, ionizing
the air and thereby discharging the capacitor slightly."

Note the statement "makes it easier for a current to flow between the
plates". That's "between the plates" and not "flow to earth".

snip

"It is true, most capacitors tend to self-discharge about 50% in something
like 15 minutes."
That's "self-discharge" and not "discharge to earth".

For a detailed discussion of electrons, why not try posting on one
of the Physics or Science newsgroups?

Regards, Ian.




Ian[_5_] June 23rd 12 04:37 PM

loop antennas and noise suppresion
 
"Szczepan Bialek" wrote in message
.. .
Troll or moron? You decide.


" Variable capacitors with their plates open to the atmosphere were
commonly used in radio tuning circuits."
If you have such try to measure "the Capacitor charge holding" and decide.
S*


Hi folks.

Apologies for my long posting a few minutes ago. I do not like selective
quotes but I forgot that Szczepan only understands copy-and-paste.
Of course, we all kn ow that copy-and-paste is merely the movement of
electrons flying in tight formation.

Please excuse my tryping terrors - they are merely the random movement of
heavy electrons hitting the keys on my keyboard. It's worst for me when one
falls off the keyboard and lands on my foot.

73, Ian.



[email protected] June 23rd 12 05:24 PM

loop antennas and noise suppresion
 
Szczepan Bialek wrote:

All time the electrons flow to or from the ground.


Nope.

"Let me answer some of your questions. Capacitors loose their charge both
through the insulation between the plates and through the air surrounding
the capacitor. The charge is a surplus of electrons on one plate and a
rarefaction of electrons on the other. Where the electrons are compacted
(the negative plate) the electrons tend to push each other off. Where there
is a deficit of electrons (the positive plate) electrons are attracted from
other sources - air, the positive plate. Both of these actions tend to
decrease the potential difference between the plates... to discharge the
capacitor. From: http://www.newton.dep.anl.gov/askasc...0/phy00900.htm


A valid statement but you have no clue what it is talking about or what
any of it means in the real world.

It has nothing to do with what is being discussed.

" Variable capacitors with their plates open to the atmosphere were commonly
used in radio tuning circuits."


Again, a valid statement but you have no clue what it is talking about or what
any of it means in the real world.

It has nothing to do with what is being discussed.

If you have such try to measure "the Capacitor charge holding" and decide.


This is just babble.

You are an idiot.




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