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On Tue, 16 Dec 2003 02:45:14 GMT, (Bob) wrote:

On Mon, 15 Dec 2003 07:05:02 GMT, (Steven
Shelikoff) wrote:

On Mon, 15 Dec 2003 05:06:35 GMT, (Bob) wrote:

On Sun, 14 Dec 2003 17:31:13 GMT, (Steven
Shelikoff) wrote:

On Sun, 14 Dec 2003 11:29:19 -0500, Jean Dufour
wrote:

VHF waves work "line of sight". They may be slightly curved around the horizon but
they won't be much. So, whatever the power of the transmiter is, they won't reach
more than 25 miles before getting lost in space.

Well, not really. It all depends on antenna height. From the Jersey
shore, not only can I talk to the Cape May CG station, but also to
Baltimore and Chincoteague, Virginia. I have fairly reliable
communications with CG stations up to over 100 miles.

ducting...dangerous to rely on for reliable communications...

It must be a pretty reliable duct because I hear the Baltimore CG
station almost all the time from the Jersey Shore. It's faint of
course, but perfectly readable.

there are 2 considerations here.

1 is that hearing is not necessarily communications. that you can hear
them doesn't mean you can reliably communicate

I hear them almost all the time. The only times I've talked to the
baltimore station, they heard me.

the 2nd is that the ducting responsible for this can disappear,
literally, in a second.

I talked to the baltimore station a couple of times over the course of a
few hours. They heard me.

The point is that VHF signals *always* can go further than the
calculated straight line of sight horizon, and frequently can go much
further.

Steve