"Jeff Liebermann" wrote in message
...
On Sun, 24 May 2009 04:04:52 GMT, "Jerry"
wrote:

Have you considered flush antennas, like slots?

Slot antennas have the maximum lobe perpendicular to the rocket axis.
There's very little signal below the rocket. This is why tracking
stations are far away from the launch site. If the rocket were
overhead, and going straight up, there's no signal.

Slot antennas are also a power waste. You need 4 slots, run by a
power splitter, in order to insure that at least one antenna is
oriented in the direction of the receiver. Meanwhile, the other 3
slot antennas are radiating power to nobody in particular. Say goodby
to about 3/4th of your tx power. Receive sensitivity is not
affected.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558

Hi Jeff

Why are you so negative?? I have designed and built lots of slot
antennas that were widely used on military aircraft. The efficiency is
quite good. I am sure a smart guy like you could design a slot antenna and
locate it for those guys with the 3G rocket. There hasnt been any text
that restricts where the slot could be located. As I read the original
post, they werent receiving signal from the accending rocket. Maybe they
only want to receive data that was recorded after the rocket reached it's
peak. There are lots of information that you and I dont yet know. But,
my major question for you is "Why are you so negative?".

Jerry KD6JDJ