"Angela & Gary" wrote in message
...
I am planning to construct a vertical dipole array for 20m. The
electrical calculations are complete (with help from LB Cebik) and now
I'm looking for some advice on the physical construction. I'd like to
use Al tubing and find unfortunately that this is difficult to come by
locally. I will likely obtain this then from Texas Towers and therefore
the tubing lengths will be limited to 6 ft each. They do offer nesting
sizes so the real question is what diameter to utilize for the lower
most 6 ft segment (dipole being some 34 ft or so). Recalling the approx
dimensions of commercial vert antennas I've had in the past leads me to
believe that 1.25" or so would be sufficient. Comments/advice ?? I
would like to do this without guys if possible and plan on attaching the
lower-most segments to 4x4's. Thanks in advance all.

Gary
Al and emt will bend in the first good wind. I have used top rail for chain
link fences with good success. Sections are made to fit together and can be
drilled and pinned together with a bolt.