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Old August 8th 08, 07:14 PM posted to rec.radio.amateur.antenna
Richard Clark Richard Clark is offline
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First recorded activity by RadioBanter: Jul 2006
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Default Blackberry power level 4.9GHz

On Fri, 08 Aug 2008 11:00:22 -0400, Michael Coslo
wrote:

I'm looking for those who think it isn't dangerous to have the courage
of their convictions.


Hi Mike,

Unfortunately, by your conjecture
I always issue the challenge of
taping a wire from a 5 watt RF source to their temple.

this implies a co-equivalent risk where neither activity have any data
to support that a risk exists. Merely having a fear does not create
that missing data or Saddam's WMD would have been on display in the
white house rose garden.

Haven't found any yet. They actually might be on to something, they just
don't know it.


They actually might be grossly ignorant is more appropriate. The
positive spin is that with great fortune in luck, desire, or hope that
they (there is nothing "actual" involved) might (the illusions of a
gambler betting against the house) be on to something (a fog of
correlation masquerading as causation).

Those with the courage of conviction have more self-assurance than to
drop their lives to join any contest in a flood of whim. What your
challenge would reveal is quite the opposite: those who lack
faculties, are insecure, and hopelessly embrace the latest
superstition. Some swing their banners here without needing an
inviting challenge.

Let's simply return to:
With my Blackberry about
5 feet away, the analyzer is showing a -10dbW (yes, 100mW) on a 2.4
gig antenna.

and examine this from first principles.

5 feet away from an uncalibrated antenna (the emission is at twice the
"2.4 gig antenna" whatever that means) is also 15 wavelengths away
(probably more, but 15 is certainly instructive). Is this a gain
antenna? That would remove some of the hot-house steam from this
orchid's appeal. The breathless "yes, 100mW" is the dazzle of looking
at the sun through binoculars.

However, let's put the issue of gain aside and accept this valuation,
along with the only known facts - that same 15 wavelength separation.
A simple model performed using a free version of EZNEC, employing a
clear path, no disturbing environment (like a skull), and perfect,
lossless matching of source and load gives a path loss of 45dB. That
report of "yes, 100mW" requires the Blackberry to source something
closer to 5KW.

It is more likely that -10dbW was "actually" -10dBm; and I am tempting
credulity to even allow that.

73's
Richard Clark, KB7QHC