On Fri, 6 May 2005 10:28:17 -0400, "Fred W4JLE"
wrote:
You might take a look at slot antennas.
wrote in message
.. .
I've voulenteered to help the SDSU mechanical engineering studens get
telemetry from their rocket see:
http://www-rohan.sdsu.edu/~sharring/sdsurocket.html.

I have all the electronics working, I'm using a commercial 910Mhz
telemetry radio, I have every thing working except the antenna.

Fred has the right idea given the construction materials, and the need
for obstruction-free (much less friction-free) elements.

However, no one has actually responded to your concern about pattern.

With you or your trackers occupying the area directly below the rising
rocket, this places you in the null of a vertically polarized antenna
of conventional length. However, if you lengthen the radiator to
several wavelengths, this will produce radiation lobes that reach down
toward ground control, rather than out towards the horizon (where you
are not).

73's
Richard Clark, KB7QHC