On Sat, 02 Sep 2006 19:51:30 +0200, Mxsmanic
wrote in :

Larry Dighera writes:

Hence the popularity of Active Noise Reduction headsets.

Then why not apply the same logic to the radio channel itself, and
reduce its noise as well.

I would guess that noise-blanker and noise-limiting circuits are
incorporated in the current radio designs.

Do you use an ANR headset?

No. The source of the noise is not anything around me, it's coming
from the channel itself.

Other than the occasional heterodyne squeal that occurs in the
receiver when two transmitters are transmitting on the same frequency
simultaneously, there shouldn't be any other noise. Ignition noise
should be suppressed by Faraday shielding, and generator/alternator
noise should be bypassed to ground.

What is the nature of the noise you are hearing? Can you describe it?
Is it a hum, pulses, growling, squealing, what?

What would you estimate the cost of re-equipping all aircraft with
such a system might be?

They don't all have to be reequipped at once, any more than everyone
must have a glass cockpit.

Regardless of when it occurs, there will ultimately be an additional
cost.

And to expect the old (current) communications system to remain
operational while the new system you are proposing is operating
concurrently won't be feasible if they use the same frequencies. If
an new alternate frequency band is used for the new communications
system you are proposing, it could work. But getting the FCC to
allocate additional frequency spectrum will probably be opposed,
because the frequency spectrum is a finite resource, and there are
many more services desiring to use it than there is bandwidth
available.

You really should read the information at some of the links I provided
to get an idea of what has been tried, and what is on the FAA's
horizon regarding aviation communications. This topic has been very
thoroughly researched by government personnel and it's unlikely that
you will hit upon a superior system to what the professionals have
examined.