[TowerTalk] FCC Soil Conductivity Maps

Jim Brown jim at audiosystemsgroup.com
Tue Feb 9 19:05:01 EST 2016


On Tue,2/9/2016 11:49 AM, jimlux wrote:
> It's useful for deciding "are we building our AM transmitter in a good 
> or bad conductivity location"

That's a rather secondary use of these maps. Primarily, they are used in 
conjunction with families of curves, one family for every 80 kHz or so 
of the AM broadcast band, to predict ground wave coverage. These curves 
are part of the FCC Rules. In the FCC Rules, an important criteria for a 
new broadcast station is non-interference with existing stations. 
There's one standard for stations on the same channel, another for those 
on the first adjacent channel, and a third for those on the second 
adjacent channel.

73, Jim K9YC



More information about the TowerTalk mailing list