Below is a link to a video describing the development work on an
interesting concept for an antenna:

http://www.youtube.com/watch?v=9tIZUhu21sQ

RF

On Sep 6, 9:56*am, Richard Fry wrote:
Below is a link to a video describing the development work on an
interesting concept for an antenna:

*http://www.youtube.com/watch?v=9tIZUhu21sQ

RF

magnetic coupling to the stream seems kind of odd, but it appears to
work for him. i wonder what happens if you go qro? i would expect
some heating of the water and maybe even some ionization or corona
that might cause instability in the stream. i would also guess the
tuning would be difficult in high winds.

On Sep 6, 10:59*am, K1TTT wrote:
On Sep 6, 9:56*am, Richard Fry wrote:

Below is a link to a video describing the development work on an
interesting concept for an antenna:

*http://www.youtube.com/watch?v=9tIZUhu21sQ

RF

magnetic coupling to the stream seems kind of odd, but it appears to
work for him. *i wonder what happens if you go qro? *i would expect
some heating of the water and maybe even some ionization or corona
that might cause instability in the stream. *i would also guess the
tuning would be difficult in high winds.

If anything is to occur it would be at the toroid which the water is
flowing thru. In this case the
diamagnetic material is the prime mover with respect to toroidal
field.
What the feed line is doing is not mentioned and it could well be the
toroid windings alone is doing all the radiating

On 9/6/2010 10:28 AM, Art Unwin wrote:

...
What the feed line is doing is not mentioned and it could well be the
toroid windings alone is doing all the radiating

Watch the video again. If we can believe that the video has not been
manipulated then, the signals are not present until the water flows ...

I seen this done many moons ago with a thick quartz tube(s) and a column
of mercury, mercury height varied to tune ... I'll bet the "mercury"
antenna is/was immensely more efficient ... the magnetic coupling would
be a great aid in NOT having to tune the match constantly ...

Regards,
JS

On 9/6/2010 8:59 AM, K1TTT wrote:
magnetic coupling to the stream seems kind of odd, but it appears to
work for him. i wonder what happens if you go qro? i would expect
some heating of the water and maybe even some ionization or corona
that might cause instability in the stream. i would also guess the
tuning would be difficult in high winds.

Wind would seem to be a weak point. The top of the conductive stream
would dissipate at different heights depending on the wind velocity, so
a gusty wind would be constantly altering the effective antenna length.

Roy Lewallen, W7EL

On Sep 6, 2:00*pm, Roy Lewallen wrote:
On 9/6/2010 8:59 AM, K1TTT wrote:

magnetic coupling to the stream seems kind of odd, but it appears to
work for him. *i wonder what happens if you go qro? *i would expect
some heating of the water and maybe even some ionization or corona
that might cause instability in the stream. *i would also guess the
tuning would be difficult in high winds.

Wind would seem to be a weak point. The top of the conductive stream
would dissipate at different heights depending on the wind velocity, so
a gusty wind would be constantly altering the effective antenna length.

Roy Lewallen, W7EL

Part of the speal given talked about the scarecity of real estate for
the many antennas on ships! Why don't they use non frequency dependent
antennas so antennas can be shared, especially when in combat? And
what do submarines use for antennas
when in the stealth mode?

On 9/6/2010 4:41 PM, Art Unwin wrote:

...
Part of the speal given talked about the scarecity of real estate for
the many antennas on ships! Why don't they use non frequency dependent
antennas so antennas can be shared, especially when in combat? And
what do submarines use for antennas
when in the stealth mode?

Antennas which pop up out of the deck plating would be something. That
idiot has just developed a very expensive toy ... and a very poor one at
that.

Regards,
JS

On Sep 6, 11:41*pm, Art Unwin wrote:
On Sep 6, 2:00*pm, Roy Lewallen wrote:

On 9/6/2010 8:59 AM, K1TTT wrote:

magnetic coupling to the stream seems kind of odd, but it appears to
work for him. *i wonder what happens if you go qro? *i would expect
some heating of the water and maybe even some ionization or corona
that might cause instability in the stream. *i would also guess the
tuning would be difficult in high winds.

Wind would seem to be a weak point. The top of the conductive stream
would dissipate at different heights depending on the wind velocity, so
a gusty wind would be constantly altering the effective antenna length.

Roy Lewallen, W7EL

Part of the speal given talked about the scarecity of real estate for
the many antennas on ships! Why don't they use non frequency dependent
antennas so antennas can be shared, especially when in combat? And
what do submarines use for antennas
when in the stealth mode?

i would tell you, but then i would have to kill you!

K1TTT wrote:
On Sep 6, 11:41 pm, Art Unwin wrote:
On Sep 6, 2:00 pm, Roy Lewallen wrote:

On 9/6/2010 8:59 AM, K1TTT wrote:
magnetic coupling to the stream seems kind of odd, but it appears to
work for him. i wonder what happens if you go qro? i would expect
some heating of the water and maybe even some ionization or corona
that might cause instability in the stream. i would also guess the
tuning would be difficult in high winds.
Wind would seem to be a weak point. The top of the conductive stream
would dissipate at different heights depending on the wind velocity, so
a gusty wind would be constantly altering the effective antenna length.
Roy Lewallen, W7EL
Part of the speal given talked about the scarecity of real estate for
the many antennas on ships! Why don't they use non frequency dependent
antennas so antennas can be shared, especially when in combat? And
what do submarines use for antennas
when in the stealth mode?

i would tell you, but then i would have to kill you!

Naahhh.. everyone knows they drag an insulated wire, which is why NEC
was updated some years ago to handle insulated wires in a conductive medium.

Now.. when their periscope is up, indeed, there's a lot of special stuff
that goes into shared apertures. Look to the work of Jaumann in WWII..

And with sharing apertures.. it's not so much non-frequency dependent
radiators that is the problem, it's isolation between the Tx and Rx.
Multimegawatt pulses from your radar tend to raise cain with your
sensitive receiver, even if your diplexer does have 100dB isolation.

Finally, it is challenging to make something that can efficiently
radiate at a frequency while not reflecting that same frequency (i.e.
re-radiating). Brings a whole new meaning to "match at the feedpoint"
when your RCS has to be a tiny, tiny fraction of the physical size.
(for reference, the RCS of a resonant dipole with shorted feed is about
0.2 lambda^2)

"Roy Lewallen" wrote in message
...
On 9/6/2010 8:59 AM, K1TTT wrote:
magnetic coupling to the stream seems kind of odd, but it appears to
work for him. i wonder what happens if you go qro? i would expect
some heating of the water and maybe even some ionization or corona
that might cause instability in the stream. i would also guess the
tuning would be difficult in high winds.

Wind would seem to be a weak point. The top of the conductive stream would
dissipate at different heights depending on the wind velocity, so a gusty
wind would be constantly altering the effective antenna length.

Roy Lewallen, W7EL

Let's fix the wind problem and shorten the antenna!
Have the water spray up into a receiving vessel the distributes the water
into
5 or 6 radial tubes that make up a capacitive hat. :-)

While we're at it, let's spray out some radials for a counterpoise!

Hey, if we can catch all the water and recirculate it, then we can
add material to increase the conductivity of the water.
ok,ok I'll stop.
MikeK