[RFI] Steel House Grounding Question

Colburn kd4e at arrl.net
Sun Oct 26 17:44:02 EST 2003

We are about to break ground on a new steel home.  The skeleton is red 
iron, the roof and walls steel, the studs throughout are steel. The pins 
for the uprights are set into the concrete pour (not sure if they 
protrude through the slab/footing into the soil below).

The house is located about 200 feet from the base of a row of new towers 
carrying very high voltage lines.  I do not detect any rfi, nor is there 
any likelihood of BPL.

1.  Any possibility of inductive coupling into the building, tower, or 
long wires?  (I presume that being several hundred feet line-of-sight 
from the power lines, vs the base of the poles, would eliminate that).

Several questions re. good grounding, lightning, and rfi defense:

2.  Do I need to request that the pins be tied to 8 foot ground rods 
under the concrete to assure a lower-impedance ground path or will the 
energy be so distributed across the building as to not be a worry?

3.  One of the six major uprights in the skeleton is in the corner of 
the new radio room. When I bring the feedlines in from the tower and 
wire antennas should I ground them to the upright via Polyphaser or 
equivalent lightning protection devices?

4.  If I am grounding lines to an upright should that one upright have 
extra ground rods?

5.  Do I correctly assume that I will need a balun outside the house and 
to bring my open line in via coax?  I am guessing that even if I center 
the 450ohm commercial slotted line in a 4" PVC through the wall that the 
mass of steel will create problems?

6.  Any other suggestions re. Ham Radio and steel buildings before we 
finalize things?

Thanks! & 73, doc kd4e

More information about the RFI mailing list