[Elecraft] Lightning season is on the way in New Mexico.

[Don Wilhelm]

   Phil,

Before you do anything else, get enough #6 or #4 bare copper wire to 
connect that new ground rod to the Utility Entry Ground for your house.  
The wire should be buried to keep it out of the way of mowers, etc., but 
the connection is more important than where the wire runs.

First, it is required by National Electric Code, and 2nd because it is 
dangerous without it.  Should you have a ground fault in your house 
wiring, everything connected to that isolated ground rod can carry the 
ground current - touching anything within the area that is connected to 
the house wiring, but not to the ground rod at the same time as touching 
those items which are connected to the ground rod can cause 
electrocution.  I would bet you were not planning to ground the desk 
lamp to your new ground rod - so run that ground rod to ground rod 
connecting wire for your safety and your family and pets.

Now back to your original question - I would use stranded #14 or #12 
wire because it is sufficiently flexible and easily managed.  Solid 
copper wire will break if flexed (by moving equipment around on the 
desk), and braid from RG-8 is a bit messy to deal with.  Use ring tongue 
terminals on each end of the wire (crimp if you have the correct tool, 
solder if you do not).  Yes, ring tongue terminals require that you put 
the ground screw through the terminal hole, but do provide a better 
connection than other terminals with an open end that allow connection 
without putting the screw through the hole.  To attach to your copper 
pipe "buss bar", drill it with a small diameter drill (1/8 inch) and use 
self-tapping metal screws (#6 or #8)  The connections should be tight.  
I prefer solid copper bar over a pipe because I can use a stainless 
steel screw with internal toothed lockwasher and a nut to maintain 
tightness.  Normal plated hardware can react with copper and the 
connection can fail with time and corrosion - use stainless steel to 
minimize that reaction.

Still, that is not sufficient protection for lightning - it will bleed 
off static charges from distant lightning surges, but make sure your 
antenna system has a DC path across the coax, and use surge protection 
devices (PolyPhaser or other) on your coax.  In addition, I would advise 
using an antenna switch in the shack to switch between the coax runs to 
the shack, and put a dummy load on one of the selections - switch to the 
dummy load when the transceiver is not in use.  And make a DC path 
across the coax to the transceiver/amplifier at the switch.  A 100 uHy 
choke of sufficient current capacity for your maximum power will do, or 
alternately a 5k to 10k resistor (I would suggest 5 or 10 watts for your 
SB-200 power level).  If you do not want to open your antenna switch and 
add it to the coax going to the transceiver/amplifier, then mount the 
resistor (or choke) in a PL-259 from center conductor to the shell and 
use a UHF Tee Adapter at the input of your antenna switch - the coax to 
the transceiver/amplifier connects to one side ot the TEE and the PL-259 
with the resistor or choke connects to the other side - the 3rd (male) 
end of the TEE goes to the antenna switch input connector.

All in all, simple grounding is not simple, other measures must be 
employed in lightning prone areas.  But your first step is to connect 
that isolated ground rod to the Utility entrance ground - that is a 
personnel safety issue and is much more important than protection for 
your equipment.

Much more information about lightning protection is available at the 
PolyPhaser website.

73,
Don W3FPR


On 3/28/2011 5:35 PM, Phil Townsend wrote:
> Lightning question:
>
> I have driven an 8 foot copper clad rod just out side my operating station. Its about 6 feet from the rod to my desk.
> I have attached a solid copper wire (1/4" thick) to the ground post (with a ground rod clamp) The wire goes thru the wall and is bonded to a copper pipe that is 1-1/8" wide  that is just under the desk.
>
> So on to my question:
> What is the BEST way to connect my equipment (k3, SB-200 and a remote coax switch) to the copper pipe?
>
> Coax braid  from RG8 or solid copper wire? and why....
>
>
> Thank You guys...
>
> Phil
> Santa Fe
>
> soon to be a xx5SSR...
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