On 1-Jan-2004, "Dave" wrote:

In simple terms radios operate in line of sight.

This is true for the VHF frequencies used for conventional aircraft com
communications (118-136 MHz). HF frequencies (below around 5 MHz) bounce
off of the ionosphere and can be received well "over the horizon." That is
why HF is used for oceanic com.

That's why it is difficult to pick up transmissions from ground stations,
whereas its straight forward
hearing to aircraft.

To hear ground stations you either need to be close to them on the ground
or in the air.

Yes, picking up a distant VHF ground station while on the ground is
unlikely. Just how far away one can be and still get a usable signal
depends upon terrain and heights of antennas (at both ends).



A bigger (higher) ariel will help.

MAYBE!!!


I have for some time thought that it would be neat if the FAA (or some other
institution), as a PR and educational initiative, put some selected ATC com
interchange on the web in real time streaming audio. Maybe a busy JFK
RAPCON frequency would be a good choice. ATC coms are public domain (i.e.
they are not protected as private communications) so their re-broadcast on
the Web would be perfectly legal.

--
-Elliott Drucker