On Sun, 23 Apr 2006 08:31:10 -0700, Wes Stewart
wrote:

On Sun, 23 Apr 2006 09:43:00 -0400, Buck wrote:

On Sun, 23 Apr 2006 06:17:35 -0700, Wes Stewart
wrote:

On Sun, 23 Apr 2006 08:08:46 -0400, Buck wrote:

[snip]

In other words, a 6 element beam of some given element spacing has a
(number from the air) gain of 6db. A twelve element version with
twice the boom length will be in the ballpark of 12 db gain.

You want to rethink this? I've always figured 2.5 - 2.6 dB increase
for each doubling of the boom length (or array size) for practical
purposes.

That's pretty close. I don't know the exact numbers and my numbers
are just ballpark. yours may very well be more accurate. I haven't
tried modeling for accuracy, just what I remember reading about
antennas. If you build a 2 lambda antenna and a 4 lambda antenna, they
the 4 will have about the same gain as a pair of 2 lambda antennas
phased, which is about, but not necessarily exactly double the gain of
one antenna.

give or take 1/2 db, what is that to signal strength anyway?

Quite a bit on an EME path.


BTW, going from 6 dB to 12 dB isn't a two times increase.


you are right. A 6 element antenna to a twelve element antenna or
double boom size is about 3 db gain, double power. Sorry.
--
73 for now
Buck
N4PGW