Radio Grounding

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Here I will document the progress of building a ground system for the home station.  I currently have an entry plate installed on the end of the house near where the coax assemblies exit into the free world.  Currently the ground wires are 4 ga bare stranded, this is being changed out to flat copper strip.  I figured the stranded was better than nothing while I am building.

I started to make copper clamps to attach the strip copper to the ground rods.  I elected to build the clamps as opposed to purchase as I had some copper bar stock in the metal bin and it's more fun to make chips than shop on the internet!

Machining the half round

I used a 5/8" high helix ball end mill to cut a channel 1/2 the diameter of the ground rod down the length of the copper bar.  This will allow me to make contact with half of the diameter of the rod along 4" of its length.  The joint will be treated with anti oxidation paste upon assembly.

Completed half round cut

Here is the inside of the channel prior to deburring after tapping for three 10-32 SS Allen cap screws.

Completed section with strip clamp

The completed contact assembly.  The mechanism to clamp the contact to the copper rod comes next...

Clamp dummied up on a piece of bronze rod and using the inadequate tin clamp bar that came with the U-bolts.  The U-bolts ride nicely on the heads of the fasteners that hold the two halve together.

 

Another shot with the newly made clamping bars made from 1/2" light gauge steel tubing.  The U-bolts will be cut back in length during installation.

 

Entry Point

Here is the coax entry point for the house, prior to the addition of the PolyPhaser for the Hex Beam.  I ran a 2" grey PVC electrical conduit in to the attic and down into a centrally located linen closet.  The foam keeps scorpions out of the house...

Interior end of conduit

Here is the end down in the closet. 36' from the entry plate to this end of the conduit.

View of the complete assembly.  The braided grounds are being replaced with copper strip.  There are three PolyPhaser units in a line on the plate.  From Left (hidden) to right they are Hex Beam, VHF/UHF and long wire.  All connections are scuffed bright with Scotch Brite, treated with No-Ox and fastened with stainless steel hardware.  All items are mounted along a horizontal "protection line" across the plate.

 

The box at the left is a rotor control lightning protector from Array Solutions.  At the very  right of the image is a diplexer that splits off the 6 meter signal from the 144/430 mhz.  There are two antennas on a mast above this point, a Ringo 6 meter with a home made radial kit and an Arrow dual band J-pole.  The PolyPhaser for the Hex Beam can be seen at the very right end of the plate.  It is mounted on a  3/16" x 1 1/2" copper bar with a radius bend in it.  The coax runs are color coded on each end for identification.  There is room for one more bulkhead type PolyPhaser in the middle. 

 

Here is the installed ground clamp.  The 2" x 0.022" copper strip is treated with a copper based anti oxidation grease and then clamped to the clean copper plated 8' ground rod. The copper strip and grease was obtained from Georgia Copper

A shot of the copper strip coming down from the entrance plate.  A couple of supports will be added to prevent wind damage to the strip.