

Jets of seawater for radio antennae - smcl
http://bldgblog.blogspot.com/2010/11/liquid-radio.html

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wccrawford
When I first saw this, I wondered how it could possibly be cheaper or better
than just creating a metal rod of the same size.

But the ability to 'dismantle' the antenna for stealth makes sense, as well as
the ability to change the size of it on command.

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stygianguest
Antennas --especially big ones-- have a large radar cross section, i.e., very
visible on the radar. So a stealthy ship wants to avoid them. At the same
time, long distance communication requires very large wavelengths and
therefore large antennas. Temporary antennas are a good solution.

EDIT: this is of course in the article. Note to self: RTFM

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spazz
I suspect I'm not the only one tempted to convert the nearest fountain into an
antenna. Very nice indeed.

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MichaelApproved
The fountain part of the video didn't make sense to me. I suspect the salt
that would be added to the water in the fountain would have a corrosive effect
on it.

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JshWright
Wouldn't the stream of water be pretty easily deformed by wind or the motion
of the ship?

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mattmanser
He says in the article that you need 70-80ft for HF, 6 ft for VHF and 2 ft for
UHF, so I would guess so.

However they do also say you can use plastic tubing with it, so I guess
carrying around 6ft wouldn't be hard, though how practical that would be in
rough conditions is questionable.

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catechu
Would the magnetic field required be detectable by other means, offsetting the
stealth?

If not, that's pretty neat. Now to make an iPhone app for it...

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icegreentea
Magnetic anomaly detectors are already used by many navies for submarine
hunting and minesweeping.Typically mounted on aircraft. They use to use
similar equipment in the Vietnam war to detect truck ignition coils.

So quite possibly the magnetic field could be detected. On the other hand,if
you're transmitting radio, then you can be detected. And if you had an normal
antenna, that also sticks out like a sore thumb on radar. It took a LOT of
work to get the radars on the stealth fighters not to light up like a
Christmas tree. If you could set up your transmission to be fast enough (burst
transmission), then your magnetic field would be up for too short of a time to
be useful (possibly), much faster than a mechanical antenna can extend and
then retract.

Basically, I'm sure they thought of that. War is their business, they tend to
be pretty good at it.

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gaius
_War is their business, they tend to be pretty good at it._

We were talking about incentive programmes here just the other day...

