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Old February 18th 11, 06:20 PM posted to rec.radio.amateur.antenna
Szczepan Bialek Szczepan Bialek is offline
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First recorded activity by RadioBanter: Oct 2009
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Default A small riddle, just for fun


"joe" napisal w wiadomosci
...
Szczepan Bialek wrote:

Transmitting antenna is like electron gun.


If electrons leaving the antenna are what makes it work, then please
explain how an antenna coated by an insulator like plastic or fiberglass
works.


Permittivity is material and frequency dependent. The space and an insulator
like ice and plastic or fiberglass have small value.
Water has 81.

An antenna covered with ice works. But if the ice is melting and the all
pores are filled with water the antenna do not work.

The key issue is the net DC current. Of course as a result of ansymmetry.
More electrons flow up then come back.

This net result is easy to measure.
S*
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