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eHam Forums => Elmers => Topic started by: KK4AXX on July 04, 2012, 06:28:38 PM



Title: Grounding Coax
Post by: KK4AXX on July 04, 2012, 06:28:38 PM
I bring my coax into the house via a window board with assorted pass-throughs.  Not ideal, but it is required at the moment.  All of the SO-239s are tied to a common ground with the rest of my set-up and home, (a series of ground rods tied to the service ground).  I did this with 5/8 inch ring terminals under the nut on each one. 

How does everyone else do this?  Photos?  Please?


Title: RE: Grounding Coax
Post by: W5FYI on July 04, 2012, 06:44:29 PM
Ring terminals are good for static protection, but not so good as lightning protection. A better way is to use a copper plate (aluminum will do, too) and mount your SO239s through it. Also bolt your low-impedance ground strap to the plate and tie that in to your electrical ground system.

I've had good luck finding plate stock at metal salvage yards. Copper is very hard to find, aluminum is much easier. Painted steel would work, but you need to ensure that the SO-239 or feedthrough is in electrical contact with bare metal, then protect the metal against corrosion or rust. Others will have hints as well. GL


Title: RE: Grounding Coax
Post by: K9KJM on July 04, 2012, 10:28:00 PM
Copper (Or aluminum) Roof flashing from a discount home supply store can make a good ground panel.
If using aluminum, There is the challenge of the transition to the outdoor copper system- (In most all soils, Aluminum is NO GOOD outdoors underground)

For some tips on how to do it see:

http://www.scribd.com/doc/14868226/lightning-protectiontaming-thors-thunderon-a-budget

There are a number of photos on that site.  Do give it plenty of time to load.


Title: RE: Grounding Coax
Post by: KK4AXX on July 04, 2012, 10:40:19 PM
I have a couple of pieces of 12" x 6" thin copper plate here, but I've been loath to use them with the current prices, (My Scottish blood peekin' through!  ;) ), but I can certainly make the change easily enough.  How do you recommend securing the ground wire/strap to the plate?

We are a semi-tropical, coastal environment and I try to avoid aluminum where ever possible.  I've seen aluminum tubing here turn to powder in the air just as in the ground.

I managed to scrounge up a very small amount of Penetrox when I first got into this hobby, but it nearly gone.  Is there any other, more common, chemical or compound that can be substituted?


Title: RE: Grounding Coax
Post by: AC5UP on July 05, 2012, 12:04:00 AM
Is there any other, more common, chemical or compound that can be substituted?

http://crcindustries.com/auto/?s=SL3141

Available at any auto parts store.


Title: RE: Grounding Coax
Post by: W5FYI on July 05, 2012, 06:53:40 AM
Auto parts stores and hardware stores should have something that will work. I recently bought some GB Ox-Gard at an Ace hardware store fairly inexpensively. While there, you can buy copper, brass or stainless steel hardware for mounting the ground wire to he plate. In your environment, I'd pack or spray some weatherproofing material on the completed connection.