Earthing

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gamevision
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Earthing

Post by gamevision »

Can anyone explain how i can earth a Half Wave Open Dipole Antenna..

Is there a (rational and affordable) way to protect the transmiter in case lightening hits the antenna?

Regards
Andre`
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Dr. No
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Re: Earthing

Post by Dr. No »

gamevision wrote:Can anyone explain how i can earth a Half Wave Open Dipole Antenna..
Is there a (rational and affordable) way to protect the transmiter in case lightening hits the antenna?
Regards
I live in a very heavy lightning area. We switch the exciter into a dummy load if Lightning is closer than 2 or 3 km. Usually the storms blow past our area in about 15 minutes. We run a heavy 8 gauge copper wire up the side of the mast to the base on our antenna which is DC grounded. There is one 8 foot copper grounding rod just beside the bottom of the mast as it rests on the ground, a copper clamp attaches the wire to the grounding rod.

some moisture is always near this grounding rod so the quality of the earth ground is very good. dry sandy soil is not too good without some water added. a drip irrigation emitter was diverted to emit next to the earth ground. it probably dumps half a gallon every other day into the earth. We have experienced one direct hit to date.

There is no way to perfectly protect electrical equipment. we are fortunate to have never lost any euipment to electrical storms. . . . Yet.
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pcs
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Post by pcs »

DC grounded antenna is the first step. It helps with
indirect hits, too. These can be harmfull as well.

As far as earthing for lighting protection goes,
if you don't know what you're doing its probably
better to leave this to someone who does (I'm not
suggesting Mr No doesn't).

ARRL handbook and antenna book have sections dedicated
to this topic. A simple google search will probably
yield lots of info as well, mostly from hams.
Best regards,
Marko - PCS Electronics
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