View Single Post
  #6   Report Post  
Old May 24th 09, 06:25 AM posted to rec.radio.amateur.antenna
Jeff Liebermann[_2_] Jeff Liebermann[_2_] is offline
external usenet poster
 
First recorded activity by RadioBanter: Jun 2007
Posts: 1,336
Default Piano Wire Antenna for Experimental Rocket

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