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Old January 10th 09, 03:06 PM posted to rec.radio.amateur.antenna
Dave[_18_] Dave[_18_] is offline
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First recorded activity by RadioBanter: Jun 2008
Posts: 1,183
Default How to estimate groundwave distance?

Richard Fry wrote:
On Dec 30 2008, 8:50 am, Eric wrote:
Can anyone tell me the best way to estimate the groundwave coverage
I'm likely to get on 75 meters?

___________

NEC shows this for a theoretically perfect 1/4-wave vertical monopole
system:

Frequency = 3.9 MHz
Conductivity = 5 mS/m
Applied Power = 100 watts

Groundwave Field at 10 miles = 31.7 µV/m
Groundwave Field at 20 miles = 14 µV/m

RF


Wouldn't a 200 degree vertical work better?