[RFI] Grounding system improvements, looking for comments

Christopher E. Brown cbrown at woods.net
Sun Feb 22 01:40:50 EST 2009



As we all know, a grounding system is not a magik blackhole into which RF 
vanishes, but the lower the RF impedance the better.


I need to do some drainage improvements in my crawlspace, running a fair 
bit of perf-pipe round the perimeter to the sump pump about 24 inches 
below surface.

As it happens, the end of the longest segment is < 3 feet vertical from 
the main grounding conductor.  At this closest point, it is < 5 feet from 
the main panel, and about the same to the first ground rod just the other 
side of the foundation.


It would be simple in the extreme to run a fat lead down to the trench 
where the perf-pipe is going and lay approx 35 feet of 6 inch wide copper 
flashing.


WHat are your thoughts on this as a low impedance RF ground, and would 
bottom of the trench (3 inches under the water level, covered by 2 inches 
soil, 6 inch perf-pipe, then more soil) or above the perf-pipe (8 inches 
above sub-surface water, 16 inches below grade) be better?




More information about the RFI mailing list