[TowerTalk] Station Ground

[Jim Lux]

On 10/19/14, 9:09 AM, k7mks at comcast.net wrote:
> Shack location dictates using a 25-30 foot ground level run from a new hams TS-530S to an exterior ground rod. He was planning on using #12 for the run but wonders if braid from RG-8 or a larger diameter single wire etc would offer improvement over a single wire?
>
What's the purpose of the ground wire run?
where's the point of entry into the house/structure, relative to the rod?
Neither will be a very good RF ground, if it's part of the antenna (and 
it shouldn't be).  I assume he or she is running coax from rig to 
"outside"..
If that's the case, then the RF is on the "inside" of the coax, and 
another wire from rig to outdoors isn't needed.   (30 feet of any 
conductor has significant inductance... about 10 microhenries)

Electrical safety ground (green wire)is best using the third pin on the 
plug, rather than some random ground rod. The idea of "chassis ground" 
for safety is that if the power line shorts (internally) to the chassis, 
enough current flows in the ground wire to trip the breaker, or, at 
least, to keep the "touchable" part of the device at a safe voltage.

Keeping all equipment tied together is a good idea for transient 
protection.  That means, in practical terms, run it all off one branch 
circuit, with one safety ground.  Not plugging in some stuff on one side 
of the room and other stuff on the other.  The idea is to minimize the 
"loop area" formed by ground and power wires.

Transient protection (as in overvoltage protectors: spark gaps, gas 
tubes, TranZorbs, etc.) is best done at the entry point to the structure.


Multiple grounding systems should be bonded together,i.e., to the 
house's electrical system ground, with a AWG 6 (if in a protected 
installation, e.g. along the base of the wall, etc.).