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Old February 25th 06, 07:56 PM posted to rec.radio.amateur.boatanchors
biz
 
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Default OK YOU BRAINIACS - another Question!

Simple one really ...

Why doesn't radio penetrate water ?

I mean the REAL reason.

I can see why it won't go through dirt - so radio in underground mines won't
or should'nt work very well.

But why not water ? I know low freq will penetrate water to about 50 to 100
feet depending on its strength. Light penetrates to 200 feet.

Does it vary by frequency ? I assume it does cause water vapor and rain dows
attenuate microwave signals while not effecting vhf or uhf.

Does anyome have a chart fo RF attenuation in water?

Also related - Navy did some studies in antennas. In one they noted that an
antenna enclosed in water will lower the resonant frequency. Which in
pactical terms means you could have a much smaller 80 meter dipole if you
can enclosed it within a plastic tube of water. Believe they did the
experiemnt with both fresh and sea water and the results were the same.

So... does enclose an antenna in water increase it's inductance? or
capacitance ? or both?

Just curious.. - WDØHCO - Biz