I have been searching the internet, it seems to me someone would have:

1) Constructed an airtight room, filled it with a gas such as neon and
placed an antenna in such a room. The power/freq to the antenna could
be varied and "patterns" observed in how the rf was exciting the gas
into "glowing" in the visible range while observing any visible patterns
in such.

2) Constructed gas insulated coax enclosed in a glass or plastic tube
with sufficient gap in the outer conductor where observations could be
made to see if "reflections" or other observable anomalies, and voltage
and current observed.

Anyone aware of anything close to any of this. Seems like this is right
up some universitys' alley, nasa, etc. ...

Regards,
JS

John Smith I wrote:
I have been searching the internet, it seems to me someone would have:

1) Constructed an airtight room, filled it with a gas such as neon and
placed an antenna in such a room. The power/freq to the antenna could
be varied and "patterns" observed in how the rf was exciting the gas
into "glowing" in the visible range while observing any visible patterns
in such.

Might be fun, but I don't know about useful. And, whatever antenna you
want to 'see', just scale it down to fit inside a bell jar.

2) Constructed gas insulated coax enclosed in a glass or plastic tube
with sufficient gap in the outer conductor where observations could be
made to see if "reflections" or other observable anomalies, and voltage
and current observed.

I've found a slotted line works fine to 'see' a transmission line.

John Smith I wrote in news:etus10$hop$1
@nnrp.linuxfan.it:

I have been searching the internet, it seems to me someone would have:
....
2) Constructed gas insulated coax enclosed in a glass or plastic tube
with sufficient gap in the outer conductor where observations could be
made to see if "reflections" or other observable anomalies, and voltage
and current observed.
....

Been done already, it is called a slotted line, and it is one of the
methods of direct measurement of VSWR. Not only did it allow direct
measurement of VSWR, but the position of the pattern could be observed, and
located wrt a known mismatch (typically a s/c) at the load plane. thus
allowing calculation of the complex load impedance.

Owen

Dan Bloomquist wrote:
I've found a slotted line works fine to 'see' a transmission line.

A loop of 450 ohm ladder-line works fine to 'see'
a 450 ohm transmission line. Current nodes and
antinodes are easy to detect.
--
73, Cecil http://www.w5dxp.com

John Smith I wrote:

[...]

I hear, "Been there, done that."

However, Cecil has made the comparison of optics and RF (well, he has
been the most vocal on the subject), and I do NOT dispute that there are
similarities, indeed, they may well be "one and the same." I am neither
a believer that they are, nor do I favor that they are not ... the fact
that rf behaves both as a wave and as "photons" is NOT denied ... but,
a 20,000 cycle freq can be generated by, both, a musical instrument and
a vlf osc ... one can be received by the ear, the other cannot, the
other can be received by a receiver, the other cannot ... (and yes, I do
understand about "air vibrations" and the vibrations in the EM
spectrum!--and that the two spectrums' overlap!)

However, we have not really "seen" how rf is "launched" forth from our
antennas--how it interfaces with "nothing" (or, ether) or is escaping as
bundles of photons ...

I understand the use of field strength meters, gauss meters, etc. But
still, it is not the same as "seeing." An example might be a light
meter(s)/thermometer(s) in a room telling me about a light source--but
it isn't quite the same as opening the door of that room and viewing the
light source directly, to walk the room with mirror, prism, polarizer,
magnifier, etc. in hand.

I have even went and purchased thousands of surplus neon bulbs and
strung them on mono-filament lines about an antenna, placed neon bulbs
from them and made observations on 1W-1KW+ of power to a monopole (the
energy of youth is better expended that way--I mean, it beats hanging
out in bars!--but then girls took over :-P ) I always wished I had that
roomful of neon (or other excitable gas.) I have taped the neons to
coax and observed the flow of rf on the outer connector ...

I have seen a large neon bulb in a microwave and the patterns formed in
the gas ... and it only left me dreaming of the "neon room" and full
sized antennas in such ... (yes, vhf-uhf-shf if you can't afford a BIG
room.)

I would just like to view what I proposed in the original post to this
thread, good definition pics would suffice ... yanno, a pic is worth a
thousand words ... perhaps it has been done in another country?

Oh well, one has to have something to think about ... I really have a
hard time believing (taking a "leap of faith") until I have actually
seen something, it is like that for me--but then, you already knew that
.... bad as that is, I am quite comfortable with it ...

Warmest regards,
JS

John Smith I wrote:
Oh well, one has to have something to think about ... I really have a
hard time believing (taking a "leap of faith") until I have actually
seen something, it is like that for me--but then, you already knew that

That's the problem that the "zero energy in reflected
waves" crowd have. If they admit they can see themselves
in a mirror, they have defeated their own argument. So
they must necessarily close their eyes and deny reality.
--
73, Cecil http://www.w5dxp.com

Cecil Moore wrote:

...
That's the problem that the "zero energy in reflected
waves" crowd have. If they admit they can see themselves
in a mirror, they have defeated their own argument. So
they must necessarily close their eyes and deny reality.

Cecil:

I am open to that probability, indeed, it is an excellent explanation
(theory), one I probably most favor--that "mirror argument" of yours is
GOOD! damn GOOD!

For "crissakes" man, do you think me blind? 8-) grin

Warmest regards,
JS

John Smith I wrote:
I have been searching the internet, it seems to me someone would have:

1) Constructed an airtight room, filled it with a gas such as neon and
placed an antenna in such a room. The power/freq to the antenna could
be varied and "patterns" observed in how the rf was exciting the gas
into "glowing" in the visible range while observing any visible patterns
in such.

2) Constructed gas insulated coax enclosed in a glass or plastic tube
with sufficient gap in the outer conductor where observations could be
made to see if "reflections" or other observable anomalies, and voltage
and current observed.

Anyone aware of anything close to any of this. Seems like this is right
up some universitys' alley, nasa, etc. ...

Look up Lecher Lines... Essentially the same idea.

One can also see the evidence of breakdown after the fact, by, e.g.
melted spots in coax.


Another interesting experiment is to take a plate full of marshmallows,
closely packed, and put it into a microwave oven (without the rotating
table turning)..

The mode pattern (standing waves) will be melted into the marshmallows.

Cecil Moore wrote:
John Smith I wrote:
Oh well, one has to have something to think about ... I really have a
hard time believing (taking a "leap of faith") until I have actually
seen something, it is like that for me--but then, you already knew that

That's the problem that the "zero energy in reflected
waves" crowd have. If they admit they can see themselves
in a mirror, they have defeated their own argument. So
they must necessarily close their eyes and deny reality.

As a matter of inquiry, "You ever pointed a video cam at a mirror at the
end of a hallway and seen the infinite reflections?" Quite an
interesting effect, an experiment worth doing (well, it impressed
me--but then, you know that don't take much :-( )... you might remember
having seen it done as a special effect in movies before? Perhaps the
web has an example for those without a cam?

Regards,
JS

John Smith I wrote:

I have seen a large neon bulb in a microwave and the patterns formed in
the gas ... and it only left me dreaming of the "neon room" and full
sized antennas in such ... (yes, vhf-uhf-shf if you can't afford a BIG
room.)

We do this sort of testing at JPL. We have a large bell jar (6 ft across
or so) that we put antennas and high power RF components in and then
pump down to a vacuum or fill with simulated Mars atmosphere.

Mars gas is mostly CO2, Argon, and CO.. so not far off your idea of a
neon room.