[BC] AM Grounding and Bonding

[Mike McCarthy]

Hi Andy,

I would exothermally weld 4/0 copper wire and bring one or two leads up to 
the base pier for bonding to the RF ground.  The pilings do little/nothing 
for the AM signal, but will provide one great lighting ground system. I 
would also install conventional ground rods in addition to the pilings so 
that you are not relying on structural steel for the lightning ground.

As for the bridging the gap to steel for strap...simple. I exothermally 
weld a piece of copper bus-bar to the steel, then sliver solder a piece of 
strap to the bus bar.  In some cases, you will need to add a tab to the 
base plate (butt welded to our circumference surface of the plate) for 
the  exothermic weld.

If you have Brian from NorthStar there, ask him what we did at the project 
he assisted me here.

MM



At 09:32 AM 4/9/2007 -0700, Andrew Skotdal wrote:
>We're driving steel pipe piles 55 feet down to support some new AM
>self-supporting radiators.
>
>
>
>1.      If there are nine piles below the foundation, do you ground to
>one of them or to all of them?
>2.      What type of attachment from your ground system should be bonded
>to the pile(s)?
>3.      Do you use 6 inch strap?  If so, how do you avoid electrolysis
>between the steel pipe and copper strap, and how do you avoid the
>calcium in the concrete eating your copper strap?  (Is the lack of air
>enough so you can run the copper through the cement without protecting
>it?)
>4.      Or, do you use some kind of lesser coated copper wire similar to
>a heavy gauge wire you might use in connecting studios to your frame
>room?
>
>
>
>Andrew Skotdal, President/General Manager
>
>NorthSound 1380 (KRKO-AM)
>
>2707 Colby Avenue, Suite 1380
>
>Everett, Washington 98201
>
>p.  425-304-1381 x 102
>
>f.   425-304-1382
>
>c.  425-750-5000
>
>e.  andrew.skotdal at northsound1380.com
>
>i.   www.northsound1380.com
>
>
>
>
>
>
>
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