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Grounding Tower & Shack (Advice Needed)

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Private

unread,
Aug 8, 2004, 10:53:39 PM8/8/04
to
Hello,

I am looking for some advice on if the ground system featured below is
sufficent or should be upgraded. It consists of:

- 3 ground rods 10' each around the tower (bonded together)
- 2 ground plates (one outside, one in the shack, also bonded
together)
- lightning arrestors and/or feedthrough adapters
- tower to mast ground
- interior coax switch (not shown)

I provided some pictures below:

http://www.telusplanet.net/~homac/exteriorground01.JPG

http://www.telusplanet.net/~homac/exteriorground02.JPG

http://www.telusplanet.net/~homac/exteriorground02a.JPG

http://www.telusplanet.net/~homac/exteriorground03.JPG

http://www.telusplanet.net/~homac/exteriorground04.JPG

http://www.telusplanet.net/~homac/interiorground01.JPG

http://www.telusplanet.net/~homac/interiorground02.JPG

I am looking for constructive feedback.....

Thank-you....

Lloyd

Jack Painter

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Aug 9, 2004, 12:02:17 AM8/9/04
to
Lloyd wrote

> - 3 ground rods 10' each around the tower (bonded together)
> - 2 ground plates (one outside, one in the shack, also bonded
> together)
> - lightning arrestors and/or feedthrough adapters
> - tower to mast ground
> - interior coax switch (not shown)
>
> I provided some pictures below:
>

> I am looking for constructive feedback.....

Hi Lloyd. Certainly an extremely professional appearance to the work. Great
to see such attention to detail as your station provides. Feedback now.....

Is that nice drainage-rock surrounding the tower base only a couple inches
deep? Seems the ground rods lose effectiveness for whatever depth that rock
is. Would have been fine to sink them a full 10' even after digging a 1'
deep trench and covering with topsoil. Besides gaining addtional
effectiveness from the ground, it's the exposure to air that will cause the
most need for future ground system maintenance.

Ground rods around the tower are very close together, is there room to add
additional ground rods from at least two of the legs at a distance of 10-20'
from the tower?

Tower is very close to, but not bonded to the house. Are there metal rain
gutters or metal flashing close by? Bonding to them is indicated, if so.

Is that a picture of coax shield grounding design, using the SS hose clamps?
Stainless steel is a very poor conductor and works when nothing else will -
but a copper or bronze shield-ground would be better. Andrews Wire and I.C.E
both make nice ones.

Interior surge protection for wiring is going to be a serious issue, when a
tower is that close to the structure. EMI from a direct attachment so close
will be a challenge that might indicate 200% sizing of neutral wiring,
double-ended surge protection and some very good bonding. Ground Potential
Rise will start right at your station's single point ground with a tower so
close - therefore perfect bonding including the connection to the AC service
ground is essential. In that respect, those attractive looking insulated
wires bonding the station equipment to the single point ground may be
inadequate. The bonding is the only protection from such close aboard GPR,
and individual heavy, wide copper straps could do a much better job than the
wiring shown.

All in all, I think the only major defect is the lack of additional ground
rods, as when a tower is right next to you, the desired direction for
attachment current is away, away, away. Carry it away with a ground field
that uses very heavy low impedance conductors and at least two more ground
rods. More is better considering where your tower is.

Best regards,

Jack Painter
Virginia Beach VA

**THE-RFI-EMI-GUY**

unread,
Aug 9, 2004, 12:28:09 AM8/9/04
to Private
Looks like a pretty good start. I would add a Polyphaser rotator surge
protector to those conductors passing through the terminal block on the
ground plate.

Make sure everything in your shack is bonded together, including your
computer etc. Add protection to phone lines. etc.

The other poster mentioned more ground rods. That is a good idea,
arrange them to direct the current away from your shack.

Have you bonded this ground system to the rest of the house? If not, do
so by running a conducter to the utility ground rod. Be careful doing so
as there may be a slight potential difference that will go away when
bonded. Also check your water supply. Is it mettalic? Then bond it as well.

Private wrote:

--
Joe Leikhim K4SAT
"The RFI-EMI-GUY"

"Jazz is not dead, It just smells funny" F.Z

Harry Conover

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Aug 10, 2004, 12:58:20 AM8/10/04
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radio-o...@telus.net (Private) wrote in message news:<d318809e.04080...@posting.google.com>...

Hi Lloyd,

Looks like a nice installation, although your grounding rods might be
placed farther apart, or augmented by some heavy gauge radial wires
(depending on your local ground condictivity).

What I did note missing was the mention of 'lightning chokes' wound in
the coax lines decending from the tower. These are basic to lightning
protection for broadcasting towers, but I've rarely seen them
implemented by hams.

The idea of a lightning choke is to add a small amount of inductance
to the coax so that if a direct lighting strike happens, the
instantaneous current flowing though the outer jacked of the coax into
your lightning arresters will at least have some amount of impedance
limiting the current magnitude, thus reducing the probability of
destruction of both the coax and the the arrester itself.

These chokes are more often than not implemented by winding a dozen or
more turns of coax around a form (say a 4" diameter phenolic tube)
prior to the arrester or spark gap.

Harry C.

Jack Painter

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Aug 10, 2004, 2:39:19 AM8/10/04
to

"Harry Conover" <hhc...@yahoo.com> wrote

Harry, that winding of coax may be useful as an RF choke, but it is most
certainly not a lightning choke, and will act more like an air-wound
transformer than anything else. Not only is this not specified for any
lightning protection systems, it is specifically warned against in many.

Dr. Daffodil Swain

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Aug 10, 2004, 7:12:03 AM8/10/04
to

--
Listen to Alternative News and Conversation You Won't Hear On Commercial
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Visit http://live365.com/stations/pascoradio
YOU HAVE BEEN WARNED!

First Time Users May Be asked To Do A 1 Time Setup.
"Jack Painter" <223...@cox.net> wrote in message
news:r4_Rc.12079$Yf6.1279@lakeread03...

> Hello All. First let me comment that the lightning mitigation techniques
used are better than many ham installations. That being said, I would
increase the conductor size between the tower legs and the ground rods.
When I saw these, I thought a "fast acting fuse." The amount of current
that the tower can handle cannot be safely terminated to ground with smaller
conductors.

Also, the screw terminals need to be checked periodically because they will
loosen themselve due to "cold flow." Why not repace them with crimp types
and then solder the crimp with a torch as a back up? I am asuming that this
device is covered by something to protect it from rain, etc?

John-WA4JM, Dade City, FL, home to some of the most ferocious lightning
activity in the western hemisphere.


Harry Conover

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Aug 10, 2004, 6:17:07 PM8/10/04
to
"Jack Painter" <223...@cox.net> wrote in message news:<r4_Rc.12079$Yf6.1279@lakeread03>...
> "Harry Conover" <hhc...@yahoo.com> wrote
> > radio-o...@telus.net (Private) wrote in message
> news:<d318809e.04080...@posting.google.com>...

> >


> > What I did note missing was the mention of 'lightning chokes' wound in
> > the coax lines decending from the tower. These are basic to lightning
> > protection for broadcasting towers, but I've rarely seen them
> > implemented by hams.
> >
> > The idea of a lightning choke is to add a small amount of inductance
> > to the coax so that if a direct lighting strike happens, the
> > instantaneous current flowing though the outer jacked of the coax into
> > your lightning arresters will at least have some amount of impedance
> > limiting the current magnitude, thus reducing the probability of
> > destruction of both the coax and the the arrester itself.
> >
> > These chokes are more often than not implemented by winding a dozen or
> > more turns of coax around a form (say a 4" diameter phenolic tube)
> > prior to the arrester or spark gap.
> >
> > Harry C.
>
> Harry, that winding of coax may be useful as an RF choke, but it is most
> certainly not a lightning choke, and will act more like an air-wound
> transformer than anything else. Not only is this not specified for any
> lightning protection systems, it is specifically warned against in many.

> Jack Painter
> Virginia Beach VA

Jack, while I'm sure that you believe this, I really can't guess where
you obtained such IMHO such massive misinformation.

First of all, it is the purpose the the coiled coax to act as an
inductor (r.f. choke) because this is how it resists the very rapid
di/dt common mode characteristic associated with a lightning hit, thus
limiting the peak discharge energy that the following spark-gaps and
lightning suppessors must absorb and reducing the overall peak impulse
power damage potential.

It's basically a brute-force version of the common computer technique
of placing a ferrite torroid around cables to attenuate their common
mode impulse transmission/conduction ability. Realize that with
sufficiently low SWR, currents through both the inner conductor and
outer shield of a coax are equal, summing to zero, hence there is no
net electromagnetic field produced. The same is not true for a common
mode impulse traversing the transmission line. The bottom line is that
only the common mode impulse resulting from a lightning strike will
experience the results of the "choke".

I'm not sure why you would believe that a coil of coax would act like
a 'transformer' of any type, unless the SWR is truly enormous, a
probem in itself. A case in point is that in both proton synchrotrons
(typically operating in a swept frequency range of roughly 3-30 Mhz),
and in large phased array radars (some of which operate in the UHF
range) employ multiple feeder coax transmission lines that are cut the
the same electrical length, with the cable lengths in excess of the
required physical run length being coiled up somewhere in the system.
There is no net significant electrical effect on the cable's
transmission characterists in either case.

Prior to completing my degree work at Drexel, I spent 8-years
installing and maintaining broadcast transmission systems ranging from
5-Kw to 50-Kw. This included 5 years as chief engineer in one station
(WBUD in Trenton, NJ) plus part-time work for WFIL, WCAU, and KYW in
Philly. (Additional work in 4 or 5 smaller stations.)

Quite honestly, I can't remember a single one of these that did not
protect their very costly antenna installations, transmitters, and
on-air reliability without lightning chokes employed in their
transmission lines. Still, these broadcasters use equipment that, in
general, nothing more sophisticated than your average ham station, but
on steroids! True, the average AM broadcasting tower usually exceeds
200-feet, but in an intense lightning storm, a 40-foot ham tower is
fully capable of experiencing the same energy lightning hit!

I purchased my first ham receiver, an SX-71 from a ham named Bob
Rutkowski (sp?) in Trenton, NJ. A day or so before I picked it up from
him he took an evidently direct lightning hit on his 40-some foot
crank up tower holding a 2M beam that was attached to his house. He
had grounded the outer shield of the RG-8U coax at the based of the
tower, but without a lightning choke in the coax, the hit simply
vaporized the majority of his RG-8U, his grounding connection, and
most of the final tank circuit in his rig in the basement! Not a
pretty sight!

Realize that a commercial radio broadcaster has to survive episodes
like this without disruption of their operations. Hams don't. Still
the emulation of the broadcaster's time proven protection techniques
involves only a small additional cost to an otherwise excellent
installation.

For more information, see:

Edmund LaPort, "Radio Antenna Engineering", McGraw-Hill Book Company,
New York. (My issue carries a 1952 copyright, still it's an 'oldie but
a goodie' with many subsequent editions -- and AFAIK is still the
bible of the broadcasting industry.)

IIRC, early editions of the ARRL Handbook also described this
protection technique (likely pre-1970) in the days when most hams
built their own rigs.

Harry C.

p.s., Jack, I'd love to hear a citation where "it is specifically
warned against", and why.

Private

unread,
Aug 11, 2004, 12:20:29 AM8/11/04
to
Thank-you for the advice to this point. I think I will invest in the
rotator cable ground. Not sure what to do about the lightning choke.

I don't mind replacing the antenna/mast if I receive a direct
lightning hit, I just dont want to turn be fried to a crisp.....

Lloyd


hhc...@yahoo.com (Harry Conover) wrote in message news:<7ce4e226.0408...@posting.google.com>...

Jack Painter

unread,
Aug 11, 2004, 1:10:13 AM8/11/04
to

"Harry Conover" <hhc...@yahoo.com> wrote in message
news:7ce4e226.0408...@posting.google.com...

Hi Harry - well, the web is FULL of massive information, and the old trick
of coiling coax for lightning protection is simply not specified any longer.
I will look up the sites which warned against it, citing amplification of
EMI by such a manuever, and get back to you.

>
> First of all, it is the purpose the the coiled coax to act as an
> inductor (r.f. choke) because this is how it resists the very rapid
> di/dt common mode characteristic associated with a lightning hit, thus
> limiting the peak discharge energy that the following spark-gaps and
> lightning suppessors must absorb and reducing the overall peak impulse
> power damage potential.

Arrestors AND shield grounding are specified at the TOP and BOTTOM of the
towers, and AGAIN at the facility entrance. No coils are shown in modern
drawings of lightning protection, and I have and reviewed those of one the
largest communication companies in the US.

Realistically, such a coil never had any chance of slowing down a 8us/20us
or faster attachment of 100,000,000v or even a fraction of that in the
smallest of strikes. Coax can only carry 4,500v before the dialectric breaks
down and then your SWR and balanced currents are no longer part of the
playing field. At about 5,500v the coax can no longer carry the energy by
itself and will arc over to anything nearby. So diverting 99.9% of the
energy via a fast acting suppressor and shield grounding is the only hope
for coax which does in fact take an attachment. Most times the coax does NOT
receive the direct attachment! So after shield grounding and arrestor
connection, the coiling isn't necessary in the first place, would do no
good, and can most certainly act as an air wound transformer to EMI if
"wrapped in a dozen or more turns" as you said. Even one turn. Fortunately,
coax is "resonant" (used only as an example for high-velocity and low
impedance) to a fairly small portion of the DC and AC component of a direct
attachment. Not so to the EMI near field, which any wire regardless of it's
velocity or impedance will be subject to inductive coupling of EMI. The coax
shield will absorb most of that EMI, and unless it exceeds 4500v (very
possible in a 50 percentile strike) will be diverted harmlessly to any
nearby shield ground. 12 turns of the coax shield - you do the math as you
are an electrical engineering expert here - what's the voltage out from
4000v in? Yikes.

You will Harry!

Best regards,

Jack


Jack Painter

unread,
Aug 11, 2004, 1:23:16 AM8/11/04
to
"Harry Conover" <hhc...@yahoo.com> wrote in message
news:7ce4e226.0408...@posting.google.com...


(sorry of this posts twice, ISP has newsgroup problems)


Hi Harry - well, the web is FULL of massive information, and the old trick
of coiling coax for lightning protection is simply not specified any longer.
I will look up the sites which warned against it, citing amplification of
EMI by such a manuever, and get back to you.

>


> First of all, it is the purpose the the coiled coax to act as an
> inductor (r.f. choke) because this is how it resists the very rapid
> di/dt common mode characteristic associated with a lightning hit, thus
> limiting the peak discharge energy that the following spark-gaps and
> lightning suppessors must absorb and reducing the overall peak impulse
> power damage potential.

Arrestors AND shield grounding are specified at the TOP and BOTTOM of the

>

You will Harry!

Best regards,

Jack

Jack Painter

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Aug 11, 2004, 2:00:31 AM8/11/04
to
"Harry Conover" <hhc...@yahoo.com> wrote in message
news:7ce4e226.0408...@posting.google.com...

(sorry of this posts twice, ISP has newsgroup problems)


Hi Harry - well, the web is FULL of massive information, and the old trick
of coiling coax for lightning protection is simply not specified any longer.
I will look up the sites which warned against it, citing amplification of
EMI by such a manuever, and get back to you.

>


> First of all, it is the purpose the the coiled coax to act as an
> inductor (r.f. choke) because this is how it resists the very rapid
> di/dt common mode characteristic associated with a lightning hit, thus
> limiting the peak discharge energy that the following spark-gaps and
> lightning suppessors must absorb and reducing the overall peak impulse
> power damage potential.

Arrestors AND shield grounding are specified at the TOP and BOTTOM of the

>

You will Harry!

Best regards,

Jack


Jack Painter

unread,
Aug 11, 2004, 2:10:58 AM8/11/04
to
You have a great installation - and adding a few ground rods and shield
grounds will top it off. Stay tuned for the looping coax fiasco finale....

Jack

"Private" <radio-o...@telus.net> wrote in message
news:d318809e.04081...@posting.google.com...

King Zulu

unread,
Aug 12, 2004, 10:36:21 AM8/12/04
to

"Private" <radio-o...@telus.net> wrote in message
news:d318809e.04080...@posting.google.com...

> Hello,
>
> I am looking for some advice on if the ground system featured below is
> sufficent or should be upgraded. It consists of:
>
> - 3 ground rods 10' each around the tower (bonded together)

Lightning likes to go straight. Try to have at least one ground rod
connected to the tower base at the base; the rod should be directly under
the base or as close to touching the base as possible. A 10' ground rod is
good if in conductive earth. In sandy Florida, where I tood several hits, it
took over a 20' length of ground rod (1/2" steel water pipe) to hit
conductive "hard pan". I just washed it in until it hit some solid clay,
and then washed it into the clay as far as I could.

> - 2 ground plates (one outside, one in the shack, also bonded
> together)
> - lightning arrestors and/or feedthrough adapters
> - tower to mast ground - interior coax switch (not shown)

The coax switch should be a grounding switch. Floating elements on an
antenna could actally attract a lightning hit. Also, for induced hits (not a
direct strike, but with enough voltage to damage equipment due to a nearby
strike), the grounding of the antenna lines gives the charge a nice safe
path to follow. That's better than letting the current find its own path by
arcing somewhere. I like to turn off the AC power to my entire equipment
setup when not in use. So, with the power switch on the transceiver and the
main "shack" ac power switches off, a lightning surge on the power line can
only get me or the equipment when I am actually operating. One last
suggestion: put a big (3 or 4' diameter) vertical loop (preferably near the
ground) in all tower cables going into the house. (Right over your ground
plate might be a good place.) The inductance of the loop, and the fact that
lighting likes to ionize paths in a more or less straight lines, will keep
the main current surge of a direct hit from entering your house and finding
its "home" in your power line or telephone line. I survived operating for
many years in the lightning belt of Florida and have the burn marks on my
mast to prove it. The only known damage in Florida was some induced power
that killed a couple of ICs connected to a printer ribbon cable. That was
just from the current going down the tower on the outside side of the wall.
Lightning protection is still as much art as science, Lloyd - but what you
have done so far should fairly well protect folks in the house. If lightning
is going to hit, just let it find a nice safe home - and try not to be
operating when it does. HI HI

In Florida, a house one block from us burned to the ground when lightning
started a fire in their attic. That couldn't have happened at our house, as
the lighting had a 70' tower to hit first, and a 23' ground rod to give the
current a safe place to go. We were hit - several times. So, look at your
well grounded tower as an asset for true lightning protection - not a
liability.

73
ak

Richard Clark

unread,
Aug 12, 2004, 12:07:32 PM8/12/04
to
On 10 Aug 2004 21:20:29 -0700, radio-o...@telus.net (Private)
wrote:

>Thank-you for the advice to this point. I think I will invest in the
>rotator cable ground. Not sure what to do about the lightning choke.
>
>I don't mind replacing the antenna/mast if I receive a direct
>lightning hit, I just dont want to turn be fried to a crisp.....
>
>Lloyd

Hi Lloyd,

Of the advice offered, out of the dozen or so comments, only the
addition of radials and grounding of peripheral equipment made any
sense to your already extensive installation. Adding "more" rods
sounds like hail Mary solutions. I would bet almost every house for
10 miles around you survives quite well with one.

Sure, few if any sport towers, but lightning in the vicinity is not so
choosy as to miss every house, building, or power pole simply because
they are not radio amateurs.

I also note the complete absence of discussion about the Code. All
grounds must be bonded (clamped, not screw attachment nor
solder/brazed) with a continuous wire (no breaks or splices). I also
note some rather bizarre descriptions of how chokes work (and to add
that they are not used by Hams is simply ignorance or the choice to
illustrate with poor examples).

I would suggest you mine the archives of rec.radio.amateur.antenna for
two correspondents: Richard Harrison, KB5WZI for thousands of
commercial and amateur tower installations over a career spanning 50
years (you will discover half to two thirds of suggested
embellishments are immaterial fluff); and Reg Edwards, G4FGQ for the
topic of successful ground rod application (notable in that laying
them horizontal is just as good, if not better).

As to your last comment about getting fried. You should examine that
illusion and recall that it brings voltage to mind, not current.
Voltage comes from two mechanisms common here, impedance and
resistance (the lightning strike is considered to be from a constant
current generator willing to present any potential necessary to
preserve flow). A sharp bend in a conductor is one source of
impedance change for the bad - so graceful sweeps are preferred where
you want to change direction. I note the irony of discussion where
chokes are used to build voltage (power being equal to I·E and current
being constant guarantees a build up of power beyond what would have
been suffered) to guarantee spark discharge elements firing (I suppose
so, but this sounds like Advertising Copy to sell spark discharge
elements). Most successful solutions offered here for years and years
all have the common goal of burying the lightning stroke's current
into the soil as soon as possible without any impedance to its path.
If you research the archives for low resistance paths of lightning,
you will find out how little total power is suffered in a strike
(don't fall for the monster under the bed stories of a gazillion volts
at a bajillion amps).

73's
Richard Clark, KB7QHC

Red Noise

unread,
Aug 12, 2004, 12:48:26 PM8/12/04
to
Best do a lot of research at PolyPhaser.com URL:
http://www.polyphaser.com/

Engineering notes at URL:
http://www.polyphaser.com/ppc_pen_home.asp

--
Red Noise

Michael Waldrop

unread,
Aug 12, 2004, 1:13:12 PM8/12/04
to
Having read the various post concerning coiling the coax to form a "choke",
I recall a technical article from "PolyPhaser.com", the lightning product
company. Below is an exerpt from the technical document covering Amateur
Radio lightning protection and coiling of coax cable to form a choke.

Quote:
(from www.polyphaser.com website)

Document Number PEN1016: An overview of Lightning Protection for Ham
Radio Stations


Even though the inductive properties of the coax cable appear to be
beneficial, and extra inductance can be created by adding a few turns to the
coax; don't do it. The added turns can also act like an air wound
transformer coupling more energy into the line. Make sure coax lines leaving
the tower remain at right angles to the magnetic field surrounding the
tower.

Unquote

It is my belief, based on coils and induced energy into the coil, that
coiling of the coax will induce an EMF field that can be picked up by the
coax, or other cabling, allowing it to enter into the house/shack or, more
simplified, follow a path that is not desired, i.e. the coax or rotor cable
run to the shack. Grounding of the coax at the top and bottom of the tower,
attaching coax lightning protecting products at the base of the tower and
running the remaining coax to the shack through buried metal conduit,
greatly reduces the chances of lightning strike energy from entering into
the cable(s) leading from the tower. Additionally, each leg of the tower,
not just one leg, should be grounded through it's own seperate ground rod
and each leg ground should be connected to a circular grounding system,
around the tower. The tower grounding system should be further connected to
a house grounding system surrounding the house with 8 foot grounding rods
driven into the ground and connected to the house grounding system (central
point grounding). The tower grounding system along with the house grounding
system should be connected together. The distance between the tower and the
house/shack can be lengthy. Connect the 2 systems together and add
additional 8 foot grounding rods every 16 feet along it's path.

Using buired conduit for coax and rotor cable, for example, greatly reduces
the chance of EMF fields from flowing along the coax and into the shack. A
direct lightning strike to the tower will generate an EMF magnetic field
that can be picked up by coax, rotor and coax switch cables then flow into
the house and through the equipment and/or wiring. The tower, during a
direct strike, radiate a large EMF magnetic field that can be picked up by
anything within it's path. The strength of the field reduces by a factor of
1, outlined in the Polyphaser.com technical document.

Just some technical information I've found from lightning protection
companies during my search for documentation on tower, antenna, coax and
rotor cable installation.

73's,

Mike

WB8TNJ

"Harry Conover" <hhc...@yahoo.com> wrote in message
news:7ce4e226.0408...@posting.google.com...

> "Jack Painter" <223...@cox.net> wrote in message

Jack Painter

unread,
Aug 12, 2004, 5:03:00 PM8/12/04
to
Reasons not to create a coiled-coax "choke"

http://www.comm-omni.com/polyweb/hamradio5.htm
Even though inductive properties of the coax cable appear to be
beneficial, and some extra inductance can be created by adding


a few turns to the coax; don' t do it. The added turns can also

act like an air wound transformer that can couple more energy
into the line. This is just the opposite of the desired effect.
Instead, make sure that coax lines leaving the tower remain at


right angles to the magnetic field surrounding the tower.

http://www.wrblock.com/Papers/Amatuer_Radio/APARS_P09.htm
Neatness counts - cables (transmission lines, power (ac and dc),
speaker, microphone, computer, control) should be cut to length
and routed neatly and cleanly between boxes using the most direct
practical route. The coiling of excess cable length on the
protected side should be avoided since it could act as an air-wound
transformer coupling magnetic energy from a nearby lightning strike
back into the protected equipment.

http://www.marcspages.co.uk/tech/2100.htm
Some in the RF industry would have seen coils used as static drains.
The theory is the coil is high impedance at RF and so looks open
circuit, whilst still presenting a short to the DC and draining it
to deck. The problem with them is they too can start reacting
('scuse the pun!) with the capacitance present on the system,
especially at the lower ends of the band.


24hr ops FULL COVERAGE PROTECTION (no "chokes")
http://users.erols.com/n3rr/lightningprotection/

http://www.alvarion.com/RunTime/Materials/PDFFiles/Lightning_Protection_White_Paper_March31_R41.pdf
ALVIRON SUBSCRIBER SYSTEMS TOWER LIGHTNING PROTECTION
(no "chokes")

And one major US communications company which drawings and specs
are confidential and proprietary information - but they do NOT use
any kind of coiled-coax and prohibit same from all systems.

Here's one exception - from an Amplifier and relay company - they
are NOT in the lightning protecton business and this is very
outdated advice, but shown anyway becasue we're honest!

http://www.ameritron.com/ameritron/man/pdf/RCS-4.pdf

We strongly recommend the use of lightning retarding loops
in the coaxial cables near the relay box (see illustration).
Remember that lightning travels through the path of least
resistance. Station ground leads should be solid, large surface
area conductors. Do not use braided or stranded wire for the
ground leads. Avoid sharp bends in the ground leads. Use
multiple ground rods and/or radials to provide the earth
termination.
---
Recommend you ignore this and maintain direct paths - JP

Finally, Richard Clark's mention of "code" is pretty important. Reference
the NEC-70 and NFPA-780 for US installations.

Jack Painter
Virginia Beach VA

http://members.cox.net/pc-usa/station/grounding.htm


Private

unread,
Aug 13, 2004, 1:00:06 PM8/13/04
to
Thank-you so much for the feedback and information thus far.

Although I really appreciated the information, I do not want to get
too hung up on the coiling of the coax. This weekend I plan to
upgrade the gauge of the wire from #8 to #3. Also I have now bonded
the cold water pipe entering in the basement floor to the exterior
ground plate.

Any other feedback on the pictures below are appreciated......

Lloyd


- 3 ground rods 10' each around the tower (bonded together)
- 2 ground plates (one outside, one in the shack, also bonded
together)
- lightning arrestors and/or feedthrough adapters
- tower to mast ground
- interior coax switch (not shown)

I provided some pictures below:

http://www.telusplanet.net/~homac/exteriorground01.JPG

http://www.telusplanet.net/~homac/exteriorground02.JPG

http://www.telusplanet.net/~homac/exteriorground02a.JPG

http://www.telusplanet.net/~homac/exteriorground03.JPG

http://www.telusplanet.net/~homac/exteriorground04.JPG

http://www.telusplanet.net/~homac/interiorground01.JPG

http://www.telusplanet.net/~homac/interiorground02.JPG


"Jack Painter" <223...@cox.net> wrote in message news:<9WQSc.16277$Yf6.6584@lakeread03>...

Micro MegaWatt

unread,
Aug 23, 2004, 4:11:27 PM8/23/04
to
All about grounding and lightning protection at PolyPhaser -- URL:
http://www.polyphaser.com/ppc_pen_home.asp

--
One Watt

To steal ideas from one person is plagiarism;
to steal from many is research.
-- Comedian Steven Wright


"Private" <radio-o...@telus.net> wrote in message
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