"Simon" wrote in message
om...
In an ideal situation I'd like to get the
transmission beam down to 1 degree, 10 degrees might be acceptable

Simon,

I suspect you are at least an order of magnitude too low in frequency to do
this, and have an antenna that you can easily handle. I have a 430 MHz
antenna with a 27 degree beam width, and it is 12 feet long. If this is line
of sight, use infrared.

Tam/WB2TT