Ah, the great grounding debate. Fought over by hams since Marconi was
in short pants.
I don't pretend to understand any of this stuff, but I do know that
everything involved: antenna ground, station ground, and utility ground
should be at the same potential so any strike or induced surge is even
across the entire system. How we get there is always the question.
A "single point ground" is favored by many hams, where station,
antennas, and utilities are all tied together at a single ground rod
(or multiple ground rod system). Even if this is the method of choice,
not always possible in an apartment situation. The same with
grounding rig to a cold water pipe, not always possible in an apartment.
There was an old trick of using a length of coax with capacitors at
each end between center and braid to provide a good RF ground. I
don't remember what value caps, or even how well it really worked.
The "hot mic" mentioned yesterday sound like RF in the shack. A
better ground of the rig, or a counter poise of 1/4 wavelength wire on
the desired freq may help.
73, Steve KW3A
On 4/15/2012 7:40 AM, John Miller wrote:
> Another one who doesn't know the difference in an RF ground and a lightning
> ground and the 2 should never interact any more than is absolutely needed.
> Tying them together is inviting the loss of equipment at best.
> ----- Original Message -----
> From: "Howard, W A 9 Y B W"<[log in to unmask]>
> To:<[log in to unmask]>
> Sent: Sunday, April 15, 2012 12:48 AM
> Subject: Re: grounding question
>
>
>> Tom,
>>
>> Mount the lightning arrestor directly on top of the ground rod.
>>
>> Run a ground cable # 4 or larger from same ground rod in to the shack and
>> connect it to a Brass or copper bar with screws spaced along its length
>> for
>> equipment grounds. You can either make this or purchase similar from
>> various ham radio stores. From these screws, run a ground wire to each
>> piece of equipment in your station. Do not, I repeat, do not daisy chain
>> your ground from one piece of equipment to another.
>>
>> Hope this helps.
>>
>> 73's
>>
>> Howard #3, W A 9 Y B W
>>
>>
>> ----- Original Message -----
>> From: "Tom Brennan"<[log in to unmask]>
>> To:<[log in to unmask]>
>> Sent: Saturday, April 14, 2012 8:43 PM
>> Subject: Re: grounding question
>>
>>
>>> The pole is about three feet from my window and the grounding rod is
>>> about
>>> a
>>> foot from the pole moving toard the window. Everything's just about on
>>> top of
>>> each other with the space I've got.
>>>
>>> Tom
>>>
>>>
>>> Tom Brennan KD5VIJ, CCC-A/SLP
>>> web page http://titan.sfasu.edu/~g_brennantg/sonicpage.html
>>>
>>> On Sat, 14 Apr 2012, Gerry Leary wrote:
>>>
>>>> Date: Sat, 14 Apr 2012 17:32:58 -0600
>>>> From: Gerry Leary<[log in to unmask]>
>>>> Reply-To: For blind ham radio operators<[log in to unmask]>
>>>> To: [log in to unmask]
>>>> Subject: Re: grounding question
>>>>
>>>> Do you get to put the pole in the ground? Maybe you could incorporate a
>>>> rod
>>>> there so that no one would know or see it. Then maybe you could put
>>>> your
>>>> 9
>>>> foot rod near the building.
>>>> ----- Original Message -----
>>>> From: "Tom Brennan"<[log in to unmask]>
>>>> To:<[log in to unmask]>
>>>> Sent: Saturday, April 14, 2012 4:44 PM
>>>> Subject: grounding question
>>>>
>>>>
>>>>> I'm living in an apartment where they've agreed to let me put up an
>>>>> antenna on a
>>>>> 14ft pole but they only want me to have a single grounding point for
>>>>> my
>>>>> system.
>>>>> I have a 9ft ground rod but I need both an rf ground to the radio
>>>>> itself
>>>>> and a
>>>>> ground for my lightning arrester on the antenna. Is there any way to
>>>>> ground
>>>>> these both to a single ground rod?
>>>>>
>>>>> Tom
>>>>>
>>>>>
>>>>> Tom Brennan KD5VIJ, CCC-A/SLP
>>>>> web page http://titan.sfasu.edu/~g_brennantg/sonicpage.html
>>>>
>
>
>
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