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Old February 14th 11, 10:50 PM posted to rec.radio.amateur.antenna
K1TTT K1TTT is offline
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First recorded activity by RadioBanter: Apr 2010
Posts: 484
Default A small riddle, just for fun

On Feb 14, 10:26*am, "Szczepan Bialek" wrote:
Uzytkownik "K1TTT" napisal w ...
On Feb 13, 10:18 am, "Szczepan Bialek" wrote:





In the giant Warsaw dipole was: "In the lower half of the mast, there was
a

vertical steel tube, attached to the mast's outer structure with large
insulators. This tube was grounded at the bottom, and connected
electrically
to the mast structure at half the total height. This technique works by
applying a DC ground at a point of minimum radiofrequency voltage,
conducting static charge to ground without diminishing the radio energy..
Static electrical charge can build up to high values, even at times of no
thunderstorm activity, when such tall structures are insulated from
ground.


Guess why the static charge is build up?


S*
if there is any breeze:http://en.wikipedia.org/wiki/Triboelectric_effect
or just the clear air electric field: "In fine weather, the potential


increases with altitude at the rate, according to some writers, of
about 30 volts per foot (100 V/m).[3]"
fromhttp://en.wikipedia.org/wiki/Atmospheric_electricity

You invented a new power plant. But what voltage will be there in fine
weather? In conductor must be the same. *Will it be like at bottom or as at
the top or in the middle?

The sentence "when such tall structures are insulated from ground" is wrong.
Should be: "when such *dipole works".
S*



try it and see... tie a wire to a kite and fly it up nice and high and
measure the dc voltage to ground. you can also draw current from it.
many years ago i built a motor that was powered by only a wire
sticking up about 20' in the clear air... very interesting free
power! but very dangerous near thunderstorm!