Sean Schouten wrote:
> How does that work? Don't they shield anything in airplanes?

Multiple answers:

- It's not possible to filter or shield away harmonics ON THE FREQUENCY
you're trying to receive.

- All transmitters and receivers also have IF frequencies that can be
involved in mixes, and interference problems.

- Shielding adds weight.  Aircraft engineers minimize weight.  Weight =
higher operating costs.

- Radio equipment meant for use in aircraft goes through EXTENSIVE
testing.  To test every cheap $20 cell phone that comes out every few
days, isn't going to happen.

- Operating a cell phone in flight, in a private or commercial aircraft
is illegal.

(Exception: AirCell and other companies manufacture "cellular" phones
based off of completely different cellular systems other than the
terrestrial-based ones.  They also go through the certifcation processes
listed above.)

There's more... but I wouldn't do justice to the engineers that
specialize in RF engineering for aviation...

Nate
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