there are also other ways to keep down RF in the shack. I used a set of 8 clip on RF chokes at the antenna feed point. my original reason for this was to reduce (or eliminate) common mode noise. I accidentally found out that it was also a good method of reducing unbalanced RF currents on the shield of the coax.
Now, for the house ground: I use 3 long ground spikes. One at the water main coming in from the street and one for the mains power breaker box. the Third one is my RF ground located less than 10 feet from my actual station equipment. So far, this has proven to be beneficial as far as electrical safety goes. I am also thinking on getting some 00 sized copper strap and running a connection between the rods (this will consolidate all the grounds and bring everything to the same potential).
I know that I will have to start outfitting some of the power connections in the house with RF choke devices. I have a lot of incident RF noise from 2 local broadcast transmitters.
the lesson here is this: defense in depth is always your friend.
-eric
On Aug 9, 2014, at 6:58 AM, Mark wrote:
> Hi Colin,
>
> I am sorry it took me this long to respond to your post. First, on the type
> of water pipe we have here, well, we live in the country, and use a well.
> Thus, I am not sure but it is PVC pipe right up to the well. Easy for
> whoever installed it, but bad for using as a ground.
>
> On the reasons for my wanting to install ground rods, I would like a ground
> rod near the base of the main antenna support for RF ground, and to
> discharge static charges from the dry winter winds. It may help somewhat in
> reducing nearby lightning strikes. However, I highly doubt anything will
> help with a direct strike. At 12 feet in height, my antenna is doubtful to
> be the main thing lightening is attracted to. If it were taller, I would be
> more concerned about using it as a lightening rod.
>
> On the station end of the coax, I want a second ground rod simply because
> according to everything I have read, it reduces RFI and my personal
> experience is that my internal and external antenna tuners perform better
> when grounded to an earth ground.
>
> These are the reasons I am working on grounding the station.
>
> When I lived in Kansas in the late 1980's and early 1990's I put up a dipole
> at 36 feet. It had a 6 or 8 foot ground rod. With 100 watts, I was able to
> work Central and South America on 40 meters, and even in to Hawaii. I have a
> ton of cards some ware from those days. Smile. Thus, I am a big believer in
> getting a good station ground.
>
> May the God of your choosing bless you,
> Mark (WZ0K)
>
> -----Original Message-----
> From: For blind ham radio operators [mailto:[log in to unmask]]
> On Behalf Of Colin McDonald
> Sent: Wednesday, August 6, 2014 1:44 PM
> To: [log in to unmask]
> Subject: Re: Question about Ground Rods
>
> firstly, why the ground rod, or rods?
> Secondly, the depth of the ground rod will depend allot on the type of soil
> you are dealing with.
> 6FT is typically the minimum recommended, 8 to 12 is generally better.
> Are you thinking of earth ground for lightening, or RF ground for RFI
> issues?
> Also, I would be hugely surprised, in fact, flabbergasted if your main water
>
> feed to the house was PVC. But, stranger things have been known to happen.
> I don't doubt all internal water piping is plastic, but most of the time,
> anything city side of the meter will be metal.
> There is also usually a water line access stem somewhere on the property
> that can be attached to with use of a large hose clamp.
> A general station ground is usually a good thing and you want to plant your
> ground rod as close to your operating position as possible to minimize the
> length of the wire from your ground bus to the ground rod.
> From what I recall, you aren't using any tall masts or towers...but just
> determine weather there are any trees or buildings taller than your antennas
>
> and this will give you a better idea if you need a lightening ground system
> in place with multiple rods etc.
> Personally I have never ever noticed any performance difference between
> having a ground rod and not having one. The station is grounded through
> your household electrical system already (unless you are running strictly
> battery power) so it's often redundant and unnecesary to have an additional
>
> ground.
> If you have masts or a tower taller than anything surrounding it, and you
> are prone to lightening in the area, a couple ground rods around the bottom
> of the antenna support structure is never a bad idea to help shunt that
> lightening to ground and not to your radio equipment...although, with
> lightening, you are dealing with so much voltage that equipment often gets
> fried regardless of how good your ground system is.
> 73
> Colin, V A6BKX
> --------------------------------------------------
> From: "Mark" <[log in to unmask]>
> Sent: Wednesday, August 06, 2014 11:58 AM
> To: <[log in to unmask]>
> Subject: Re: Question about Ground Rods
>
>> Hi Carolyn,
>>
>> Thank you for the encouraging words about the ground rods. Unfortunately,
>> I
>> believe all the water pipes around here are PVC. It is good to know that 4
>> foot rods might work.
>>
>> God bless,
>> Mark (WZ0K)
>>
>> -----Original Message-----
>> From: For blind ham radio operators [mailto:[log in to unmask]]
>> On Behalf Of carolyn johnson
>> Sent: Wednesday, August 6, 2014 11:25 AM
>> To: [log in to unmask]
>> Subject: Re: Question about Ground Rods
>>
>> Hi,
>>
>> I have two four foot ones that I used to use, and that seemed to do fine.
>> If
>>
>> worse comes to worse, you could always run wire to a water pipe.
>>
>> Carolyn Kj4vt
>>
>>
>> --------------------------------------------------
>> From: "Mark" <[log in to unmask]>
>> Sent: Wednesday, August 06, 2014 10:43 AM
>> To: <[log in to unmask]>
>> Subject: Question about Ground Rods
>>
>>> Hi
>>>
>>> I know that the ultimate in grounding would be to sink an 8 foot ground
>>> rod.
>>> However, the budget is dictating that should wait for a while. So, I am
>>> left
>>> with two options. First, I could just ignore grounding the antennas and
>>> radio. They are after all working pretty well right now. Or, I could go
>>> with
>>> a 3/8 inch 3 foot ground rod that fits the budget. Actually, I would buy
>>> 2
>>> of them. So, the question is: is it even worth putting down a ground rod
>>> that is less than 8 feet?
>>>
>>> God bless,
>>> Mark (WZ0K)
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