OK, I was picturing the power as on the surface of an expanding sphere from
the point of transmission (4/3 * pi * r **3) but, as I said, I wasn't sure.


wrote in message
...
On Sunday, April 20, 2014 9:17:30 PM UTC-5, Dan Marotta wrote:
That's what I would hope. I recall that, when I installed my Mode S

transponder and had it tested, it was putting out over 175 watts to the
test

equipment antenna. Don't we have an inverse cube function of power
density

to distance? I think that's right, though I probably didn't say it

correctly. Anyway, an aircraft a couple of hundred feet away would be

received in the milliwatt range, maybe somewhat more, but certainly not
at

100+ watts.





"Ramy" wrote in message

...

I am pretty sure that the suppression is based on power as well, in
addition

to altitude. So only a strong signal at the same altitude will be

suppressed. Which mean you will still get warning for same altitude until

the other aircraft is very close, giving you enough warning. I assume
this

is the same way that Zaon works. But again this is just my guess. Will be

nice if Flarm folks will comment on this.



Ramy

Dan, radiation diminishes according to the inverse square law, just as
gravitational forces or sound:
http://en.wikipedia.org/wiki/Inverse-square_law
If you double the distances, intensity falls to a quarter.