Rob Roschewsk wrote:
The sleeve idea sounds interesting.

Could I build it out of say aluminum tubing, run the coax up the center
of the tube to some sort of insulator, shield connected to the braid and
center connected to a wire extending upwards? Could I build the top half
out of tubing as well or does the radiator need to be significantly
smaller than the sleeve?

Cut two 1/4WL sections of tubing. Slip one over the coax and
connect it to the coax braid where the coax enters the
tubing. Leave the outer insulation on the coax. Don't connect
the bottom tube or the coax braid to anything where the coax
comes out. Install an insulator/support to hold the two pieces
of tubing together in a straight line dipole-like configuration.
Tie the coax inner conductor to the upper tubing. With this
configuration, you won't need additional choking on the feedline.

*******************+ ********************+
| ====================+========
1/4WL +--------------------------------- coax
| ====================+========
*******************+ ********************+

*** is the tubing, + is a connection.
--
73, Cecil http://www.qsl.net/w5dxp