Thread: The earth
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Old April 15th 12, 10:50 AM posted to rec.radio.amateur.antenna
Rob[_8_] Rob[_8_] is offline
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First recorded activity by RadioBanter: Dec 2008
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Default The earth

Szczepan Bialek wrote:
Are we discussing spark transmission and non-resonant aerials?


The earth/chassis and the field electron emission..
S*


Hey Szczepan,

Spark transmitters are not used anymore.
Try to find some more recent articles about transmitting.

Today we use nicely synthesized carrier waves that are fed to
antennas suitable for the frequency in use, not a noise generator
and transformer to high voltages connected to a random wire net.

Especially when that frequency is somewhat higher (much higer
than what Marconi and Tesla were transmitting on), there is no
need for en earth connection or even a chassis.
That is because an antenna is used that is balanced or has its
own counterpoise for the driven element.

A connection to earth would not be effective anyway, because
antennas used at higher frequencies are often several wavelengths
above the earth, and a wire used to connect to the earth would
not behave like a conductor at those frequencies.

We also operate our antennas well below the point where arcing
occurs, so we don't have to deal with electron emission.

So now please go off to a group that operates the century old
techniques that you seem to be discussing.
Maybe you can find a Tesla coil enthousiasts group where your
voice will be appreciated, although I think they are not using
sparkgaps anymore either.