Antenna System Grounding Review Requested
			 
			 
			
		
		
		
			
			Here's what I'm doing and I'd like some feedback. 
 
Antenna will be an 88ft doublet 30-40ft high supported at the center by 
a ladderlock and fed by 450ohm windowline. The windowline will drop 
down to within 8ft of the ground (above kiddie reach) where it will be 
connected to a W2DU style choke balun based on RG213 and Palomar BA-8 
ferrites. This will be enclosed in a ~12" length of electical conduit 
which will be supported to relieve the windowline of further strain. 
 
The coax will connect at the bottom of the choke enclosure via 
PL259/SO239 to a ~10ft length of RG213 down to earth level driploop and 
up into a small lockable mushroom enclosure containing a ICE300 
supported on a 5/8"x8ft copper ground rod. Also contained in the 
enclosure will be an LDG RT-11 tuner which will be mounted on the 
backside of the ground rod from the ICE300. A small RG213 jumper will 
connect the ICE and RT. The shell of the shielded DB-9 control line 
will have a small braid to bond it to the ground mounting point as 
well. 
 
The coax and shielded DB-9 control lines from the RT will drop out of 
the enclosure via PVC conduit to an undergound PVC junction box which 
has it's bottom side perforated to drain any condensate. The run to the 
house from this JB is ~50ft with a 1ft rise which should ensure a flow 
of any condensate to the JB drain. The RG213 will be direct burial 
grade but I've not been able to find any shielded DB-9 direct burial 
cable hence the electrical PVC conduit. 
 
At the house end the PVC will sweep up to another small enclosure atop 
another 5/8"x8ft ground rod holding a grounding point for the shells of 
the coax and control lines and also will terminate the line from the 
station bond from inside the shack. The lines will then enter the house 
through a driploop and travel ~5ft to the shack. 
 
At the shack a ground bus will be provided where each of the pieces of 
equipment will be bonded individually. This ground bus will be 
connected via a 3" copper strap 5ft back out to the ground rod at the 
entrance to the house. 
 
The station ground outside the house is 40ft away from the service 
entrance and its ground. I'm thinking of running "something" from the 
station ground rod to the service entrance. I can easily periodically 
"terminate" this with some intermediate ground rods if necessary along 
its length. 
 
What should the "something" running between the station and service 
ground rods be? 
 
How often should any periodic termination rods be added? 
 
Any help on direct burial shielded DB-9 cable? 
 
tnx 
jtm 
 
		 
		
		
		
		
		
		
		
		
	
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