Quote:
Originally Posted by Dave Loudin
You are correct about decibels. However, the field strength of an electromagnetic wave decays by the square of distance, not linearly.
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Yes I know that. That's why I said a
doubling of the distance results in a
quarter of the field strength. To make up for that factor of 4 drop off, it seems like the antenna would need an additional gain of 6 dB.
So that is why I was confused as to the claims of 25 miles/50 miles for the two different antennas with relatively similar gains (1-2 dB). It would seem to me that in order to claim that an antenna is good at "twice the distance" it would need a gain that is approximately 6 dB more. I'm guessing the one antenna is probably slightly better than 25 miles (maybe 30-35) and the other is slightly worse than 50 miles (maybe 40 or so). That would make more sense.
Thoughts?