"Jimmie D" wrote in message
...


snip

Ive built a couple of these and from my experience the bottom pipe is not
large enough, maybe 2.5 inches using rg58 coax. PVC may not be the best
insulator for this either. Styrofoam is very good. Even then the lower
section will have to be somewhat shorter than you would expect. Since you
are experimenting try some RG58 with your existing antenna and mkae the
change from PVC to styrofoam making the changes one at a time so you can
see
the individual effects. Also sweep the antena to find out its actuall
resoant frequency.
Jimmie

TKS. I will try both of those approaches. BTW, The PVC wasn't chosen for
its electrical characteristics. I used it only as a physical separator to
prevent arc-over. Styrofoam, eh?

The analyzer permitted sweeping, albeit manually. The resonant freq is
where it ought to be and it tests OK with the coax out of the lower section.