Antenna grounding
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OceanaRadio
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A DC-grounded antenna uses a small coil that is felt as a short to ground by DC but does not pass RF at the design frequencies of the antenna. Does it offer any protection that other antennas don't? Not in my opinion. The percentage of DC in a given lightning strike always varies, and there is a lot of DC involved. But the MAJORITY of lightning has RF characteristics, most of which is around 100 MHz. A long way from DC to be sure, and a DC-grounded antenna offers no protection whatsoever from anything but DC voltages.
Purely a sales-gimmick, it doesn't hurt to have one, but I wouldn't assume it operates any safer than other antennas. Lightning protection never takes into account whether an antenna is dc-grounded or not.
Brgds,
Jack
cberk01964
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I have a diamond discone, mounted to a tripod, bolted to the roof. My first question, is the ground clamp connected to one of the legs of the tripod sufficent?
Second, the #4 bare copper ground runs down the
"eve"(roof edge) thena gradual turn/curve and down the vertical edge of the home. Is it "ok" to tuck the wire under the vinal trim? It then connects to the 8ft ground rod.
And the final question. The distance from the home ground and the antenna ground is 25ft. Should I have a rod between these if I'm going to bond them? And is the #4 wire ok for bonding these? Thank's
Second, the #4 bare copper ground runs down the
"eve"(roof edge) thena gradual turn/curve and down the vertical edge of the home. Is it "ok" to tuck the wire under the vinal trim? It then connects to the 8ft ground rod.
And the final question. The distance from the home ground and the antenna ground is 25ft. Should I have a rod between these if I'm going to bond them? And is the #4 wire ok for bonding these? Thank's
I say again I am no expert, but here is my OPINION
From what I read #4 would be more than adequate, not sure about under the siding though, 25 feet for bonding I think some else said that additional ground rod(s) for a longer run are a good idea, if you use a 8 foot rod then, the additional rods if used should be driven every 8 feet. not sure though talk to a cellular phone tower installer, one posted on this thread and then left, haven't heard back from him.
From what I read #4 would be more than adequate, not sure about under the siding though, 25 feet for bonding I think some else said that additional ground rod(s) for a longer run are a good idea, if you use a 8 foot rod then, the additional rods if used should be driven every 8 feet. not sure though talk to a cellular phone tower installer, one posted on this thread and then left, haven't heard back from him.
cberk01964
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What about the ground clamp placment, is that ok? I imagine the entire antenna would be grounded considering it's a steel.
And what do you think the differance is if the wire is running under the siding, verse's lying on the outside?
And what do you think the differance is if the wire is running under the siding, verse's lying on the outside?
The fewer bolt friction type of connections the better, the mast is clamped into the tripod with three bolts right, according to what I read the antenna, the mast and mounting "structure" (tripod) should all be tied together for best results. For example I suppose you could use a lug on the antenna mounting bolts, and a separate stainless steel nut, in theory that would take care of the mast and antenna, add a new lug at one of the tripod to mast bolts. Personally I would keep the wire where I could inspect it periodically, I suppose if you want to cover the wire with the siding that is up to you.
Don_Burke
Member
I would run the grounding wire as high as practical to have an unspliced conductor all the way to the grounding system. A current of a few thousand amps has an interesting opinion of what a "good" connection is.
I see we can agree on something:wink:
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