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Re: Geosynchronous Satellites



>My original post quoted here:

>> Considering that the RF field falls of inversely
>> proportionally to the distance between two objects.....

>I said RF FIELD.  And then I quoted to you from a TEXTBOOK.

>I think I got that RIGHT, Phil.

Your original statement clearly implied that the *power* ("RF field")
received on the ground from a satellite varies inversely linearly with
the distance to the satellite. This was clearly wrong, as the real
rule is inverse square.

But you seem more concerned about not admitting a mistake (or at least
some highly misleading wording) than in clearing up any reader
confusion.  Sure, the strength of the *electric* field does drop
linearly with distance. But when you convert a voltage ratio into dB
you use 20*log10() rather than 10*log10() as for a power ratio.  So
the end result is the same: the *power* varies as the inverse square
of distance. And that's what's relevant.

Jon, we can reasonably disagree on subjective matters like the purpose
and values of ham radio and amateur satellites. But I take strong
exception to statements of basic physical laws that are wrong or
highly misleading.

Phil

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