[BC] AM Grounding Question

[Mike McCarthy]

As others have pointed out, there is diminishing returns past 120 
radials and anything longer than about 140 deg.  One gets maybe 2 dB 
improvement from a 90 deg system to a 180 deg. system.

I would however ask around to see if the lack of coverage is an ongoing 
reduction or has always been poor. The first scientific thing would be 
to at least look at where the 5 and 2mV contours should be and then take 
a FIM out and measure some points on either side of the contour lines 
around the site. If they're way off, then a site survey to check the 
main portion of the ground system would be in order.

The other issue would be whether they can increase power based on field 
measurements and actual contour protection.  The contour map is only a 
default tool.  Field measurements trump the map on day pattern issues. 
Talk to your consultant about that some...then consider whether adding 
to the ground system or more power outright would be preferable.

MM

On 2/14/2012 9:58 AM, Chuck Conrad wrote:
> I'm looking at a 5 KW AM in an area with very poor ground conductivity,  I'm told it is a "4".  Would increasing the number of radials (or making them longer) help with coverage?  Are there any other tricks to improve the ground situation?  I realize it is impossible to make any promises without a full site survey, but any answer in gereral terms would be appreciated.
>
> Thanks!
>
> Chuck Conrad
> KZQX Radio, QX-FM
> www.kzqx.com or www.qx-fm.com