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Old April 23rd 05, 05:10 AM
Jack Painter
 
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"Joe" wrote
If I understand correctly the just of these replies, --


I'm afraid you still didn't get the gist, Joe...

We could start over:

1.You want to set up shop in a basement.
2. You will have a Butternut vertical antenna nearby.
3. You want to know what should be grounded, and specifically where.
4. You asked about a bus-bar ground panel behind your radios.

We don't know where your main house AC power panel is, or what kind of
ground system it uses (could be the home's cold water supply pipe, a buried
copper plate, or buried copper ground rod). This will be important later,
and as others said, it is generally accepted practice and code in most
countries to require that all systems use either one single grounding point,
or bond any supplemental ground points to it. You should do at least some
basic research on your own about grounding and bonding, if this is not
abundantly clear to you.

Your vertical may or may not require the use of RF radials, counterpoise,
etc. Consult the manufacturers recommendations there, and follow them
exactly. If you do use a radial system or buried copper wires, some common
point of that system must bond to both the home's AC service ground point
*and* the radio equipment's ground rod, if separate ones are used. What you
do with your antenna and radio ground rods are entirely up to you.
Electrical codes do not cover bonding RF grounds and an separate radio
ground rod to each other. But a hundred years of sound lightning protection
science *does* require that you always bond ALL ground systems together,
NEVER leaving them isolated from each other.

It gets very expensive to provide high voltage isolation transformers
capable of safely isolating neutrals and ground systems, and while possible
this is never a goal of the hobbyist. Bonding everything should be your goal
in maintaining the basic forms of lightning protection.

Next, you can consider AC surge protection at both the AC entrance and radio
equipment. This is the protection from surge voltages that nearby lightning
imposes on either the incoming power lines, or magnetically onto the house
wiring.

Included in the category of surge protection are Surge Protection Devices
(most still call these lightning arrestors) that install in-line on your
coaxial or open-wire feedlines. These SPD's limit the amount of damaging
voltage presented to your radio's receiver circuitry.

Coax shield grounding (braid of the coax connected to ground rods at several
points as required) is what keeps damaging voltages off the exterior of the
radios, including your fingers, and limits back-flow of destructive current
out the back of the radios and into your homes AC wiring. The critical
bonding of radio and shield-grounding rods to the homes AC entrance ground
is of major importance here also. If you do not provide a very low impedance
path around your equipment, surge voltages can force one through your
equipment.

A copper bus-bar or other wide low-impedance "collector" of single point
grounding and bond points of all radios can be centered behind your
equipment as you asked. But avoid daisy chaining radios in a series to bond
them. As inconvenient and hard to conceal as it may be, individual bonding
connections from each radio, straight to the single point ground (for the
radio shack) is important. This not only provides the only approved bonding
method for lightning protection, but limits ground-loop noise between
equipments.

Hope this helps tie some of the other good posters comments together.

It's a long read, but I tried to cover most of the points of a total
lightning protection system in this website. It might clear up how important
the bonding is, I hope!

http://members.cox.net/pc-usa/station/ground0.htm

Best regards,

Jack Painter
Virginia Beach, Virginia