Subject:  Cellular phone use on airplanes (Lundquist)...
Date:     Thu, 7 Oct 1999 132145 -0500 (CDT)
From:     "Roy L. Beavers" 
To:       emfguru 
--------------------------------------------------


.......I find it more than "curious" that NONE of the published concerns
about cell phone "interference" talk about **harmonics**....

My military experience taught me that such electronic interferences were
usually the result of harmonics -- not basic frequencies.....  As has been
pointed out, for example, the FCC has selected basic frequencies to avoid
interference....  But you do not exclude the "harmonics problem" by your
selection of basic frequencies.....

Thanks, Marge, for the following....

Roy Beavers (EMFguru)......
rbeavers@llion.org.......
.....It is better to light a single candle than to curse the darkness.....
EMF-L web-site can be found at: 
EMF-L archives can be found at: 
..................PEOPLE ARE MORE IMPORTANT THAN PROFITS..................

---------- Forwarded message ----------
Date: 7 Oct 99 12:17:53 MDT
From: MARJORIE LUNDQUIST 
To: rbeavers@llion.org
Subject: Cellular phone use on airplanes

The Wall Street Journal of October 5, 1999, had a front-page story with the
headline:  "Cell-Phone Use Aloft May Not Be the Danger That Airlines Claim". 
The story points out that there is no scientific basis for the assertion that
use of a cellular phone on an airplane is likely to interfere with the
airplane's communication or navigation systems.  The frequencies of the two
are different, so interference is unlikely.

According to the story, what DOES appear to be a real problem (of concern to
the FCC) is the possibility of interference of a cellular phone in an airplane
with cellular communications on the ground.

"From high in the sky, a cell phone acts like a sponge, sucking capacity out
of the cellular sites that carry calls.  For ground users, cell phones
communicate by connecting to one cell site at a time; from the air, because of
the height and speed of an aircraft, the phones often make contact with
several sites at once.  If allowed, this would limit call capacity, which
would mean less revenue, says Howard Sherry, chief wireless scientist at
Telcordia Technologies In., formerly the research arm of the Baby Bell
telephone companies ..."

"The cellular signal from the air is also especially strong, since it is
unimpeded by buildings or other ground clutter.  That often means it can jump
on a frequency already in use on the ground, causing interruptions or
hang-ups.  And airborne cellular calls are sometimes free because the signal
is moving so fast between cells that the software on the ground has difficulty
recording the call, says Bentley Alexander, a senior engineer at AT&T's
wireless unit."

The story is on pages A1 and A8, and is worth reading in its entirety, I
think. -- Marjorie

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Reprinted with permission of Roy Beavers, http://www.emfguru.com