"Richard Harrison" wrote in message
...
Art wrote:
"David just for the record, skin depth is proportional to
frequency----."

Not exactly. Skin depth is inversely proportional to the square root of
the frequency.

For example at 1 Hz the skin depth is about 2.6 in. in copper. At 10 Hz.
it is about 0.826 in. and at 100 Hz the depth is about 0.260 in. and at
1000 Hz the depth is 0.0826 in. etc.

Best regards, Richard Harrison, KB5WZI


don't confuse him with the facts!

On Jan 23, 5:05*pm, "Dave" wrote:
"Richard Harrison" wrote in message

...

Art wrote:
"David just for the record, skin depth is proportional to
frequency----."

Not exactly. Skin depth is inversely proportional to the square root of
the frequency.

For example at 1 Hz the skin depth is about 2.6 in. in copper. At 10 Hz..
it is about 0.826 in. and at 100 Hz the depth is about 0.260 in. and at
1000 Hz the depth is 0.0826 in. etc.

Best regards, Richard Harrison, KB5WZI

don't confuse him with the facts!

My facts were correct as stated. Richard stated the "exact"
proportions
which is really nit picking. Physics books say it is "proportional"
which states that it is frequency change what affects skin depth. It
is stated exactly that way in the book
that Richard has just obtained and quoted
Art

Warning - dilletente alert! Maybe even worth an embarrassing dolt cringe

This question may have been asked before, but is there a physical
experiment that is good for verifying skin effect?

Initially, It seemed pretty straightforward, but giving some thought to
the matter indicates it "ain't necessarily so".

I'm assuming that any thick conductor is going to have "skin" to any
where I can put a sensor, so even if I drilled an internal sensor, the
drill tunnel would form a part of the skin.

Giving that some thought, is it possible to make say a ribbed conductor
that resembled a tubular heat sink, would this device allow for more
current flow because of the greater amount of skin exposed compared to a
solid tube?

Just a little thought experiment.

- 73 de Mike N3LI -

On Jan 30, 10:00*am, Michael Coslo wrote:
Warning - dilletente alert! Maybe even worth an embarrassing dolt cringe

This question may have been asked before, but is there a physical
experiment that is good for verifying skin effect?

Initially, It seemed pretty straightforward, but giving some thought to
the matter indicates *it "ain't necessarily so".

I'm assuming that any thick conductor is going to have "skin" to any
where I can put a sensor, so even if I drilled an internal sensor, the
drill tunnel would form a part of the skin.

Giving that some thought, is it possible to make say a ribbed conductor
that resembled a tubular heat sink, would this device allow for more
current flow because of the greater amount of skin exposed compared to a
solid tube?

Just a little thought experiment.

* * * * - 73 de Mike N3LI -

All charges will congregate along the peaks of the ribs so I can't see
how a greater
area is generated for utelization !
Regards
Art

Art Unwin wrote:
On Jan 30, 10:00 am, Michael Coslo wrote:
Warning - dilletente alert! Maybe even worth an embarrassing dolt cringe

This question may have been asked before, but is there a physical
experiment that is good for verifying skin effect?

Initially, It seemed pretty straightforward, but giving some thought to
the matter indicates it "ain't necessarily so".

I'm assuming that any thick conductor is going to have "skin" to any
where I can put a sensor, so even if I drilled an internal sensor, the
drill tunnel would form a part of the skin.

Giving that some thought, is it possible to make say a ribbed conductor
that resembled a tubular heat sink, would this device allow for more
current flow because of the greater amount of skin exposed compared to a
solid tube?

Just a little thought experiment.

- 73 de Mike N3LI -

All charges will congregate along the peaks of the ribs so I can't see
how a greater area is generated for utelization !


Is what you are saying then that it is not truly a "skin" effect, which
would have the maximum current riding near the surface, but rather some
sort of effect that has that maximum current getting as far away from
the center of the conductor? In other words the vertical component of
the ribbing would have current flow as if it were at that distance from
the surface of a solid conductor.

Not trying to change th eworld here, just trying to get my head around
the issue. Lot's of things have misnomers as a name.

- 73 de Mike N3LI -

On Jan 30, 12:23*pm, Michael Coslo wrote:
Art Unwin wrote:
On Jan 30, 10:00 am, Michael Coslo wrote:
Warning - dilletente alert! Maybe even worth an embarrassing dolt cringe

This question may have been asked before, but is there a physical
experiment that is good for verifying skin effect?

Initially, It seemed pretty straightforward, but giving some thought to
the matter indicates *it "ain't necessarily so".

I'm assuming that any thick conductor is going to have "skin" to any
where I can put a sensor, so even if I drilled an internal sensor, the
drill tunnel would form a part of the skin.

Giving that some thought, is it possible to make say a ribbed conductor
that resembled a tubular heat sink, would this device allow for more
current flow because of the greater amount of skin exposed compared to a
solid tube?

Just a little thought experiment.

* * * * - 73 de Mike N3LI -

All charges will congregate along the peaks of the ribs so I can't see
how a greater area is generated for utelization !

Is what you are saying then that it is not truly a "skin" effect, which
would have the maximum current riding near the surface, but rather some
sort of effect that has that maximum current getting as far away from
the center of the conductor? In other words the vertical component of
the ribbing would have current flow as if it were at that distance from
the surface of a solid conductor.

Not trying to change th eworld here, just trying to get my head around
the issue. Lot's of things have misnomers as a name.

* * * * - 73 de Mike N3LI -

What I am saying is that the ribs could prevent the flow of eddy
currents which operate as a completed circular circuit. This is how
the detection of fissures in material is found by non destructive
means. If eddy current is not present then radiation cannot occur,
thus all is not known about radiation !
Frankly I would like to know of another situation where energy flows
in the absence of a completed circuit which would provide more insight
of the circuitry of a fractional wavelength antenna, as the existing
explanation appears to be a bit to glib
Regards
Art

"Art Unwin" wrote in message
...
On Jan 30, 12:23 pm, Michael Coslo wrote:
If eddy current is not present then radiation cannot occur,
thus all is not known about radiation !

eddy currents needed for radiation, now that is a good one. do the eddy
currents do the levitating of the magical diamagnetic neutrinos?

Frankly I would like to know of another situation where energy flows
in the absence of a completed circuit which would provide more insight
of the circuitry of a fractional wavelength antenna, as the existing
explanation appears to be a bit to glib

lets see:
1. energy flows from a flame, but not back into it
2. electromagnetic waves carry energy but don't need a complete circuit
3. sound waves carry energy but don't make a complete circuit
4. water waves carry energy but don't make a complete circuit
5. magical diamagnetic levitating neutrinos flow out from the sun and carry
energy but never go back... actually a whole bunch of charged and uncharged
particles flow out from the sun in the solar wind and never go back.

Michael Coslo wrote:
Just a little thought experiment.

Something else that I have wondered about:
Given a threaded rod with about double the surface
area of a piece of tubing, does the VF decrease?
Can a threaded rod be used to decrease the length
of a resonant vertical?
--
73, Cecil http://www.w5dxp.com

"Cecil Moore" wrote
Something else that I have wondered about:
Given a threaded rod with about double the surface
area of a piece of tubing, does the VF decrease?
__________________

The velocity of propagation of Andrew HJ8-50B, 3" OD, air-dielectric
Heliax® is 0.933c.

Both the inner and outer conductors of that coaxial cable are heavily
corrugated, so using threaded rod instead of smooth tubing may not
matter much to v.p.

RF

Cecil Moore wrote:
Michael Coslo wrote:
Just a little thought experiment.

Something else that I have wondered about:
Given a threaded rod with about double the surface
area of a piece of tubing, does the VF decrease?
Can a threaded rod be used to decrease the length
of a resonant vertical?

hmmm, interesting thought. I know where I can get a 8 foot threaded rod
of the same diameter as a solid rod. Maybe an experiment in the works.

- 73 de Mike N3LI -