On Mar 30, 2:09*am, Richard Clark wrote:
On Mon, 28 Mar 2011 11:29:25 -0700 (PDT), Tom Horne

wrote:
please keep the fog index down to the degree you are able

Hi Tom,

After looking at the mile long URL to one of your offerings - I would
like to see the fog lift too.

Why don't you simply tell us what performance you want to achieve from
an antenna?

A simple quarterwave antenna built on a SO-239 connector with four
drooping radials is squat simple, cheap, and can be built and trimmed
to near perfect match in half an hour or less. *You want multiband?
Make two vertical, slightly skewed elements (each cut for the suited
band) joined at the feedpoint. *You want more gain? *How much more?
Build two or (n-times) more and spend your effort in learning to
construct feedline systems to additively join them.

73's
Richard Clark, KB7QHC

Richard
I wanted to explore whether it is practical to have my collinear dual
half wave J-pole serve as a dual band antenna. If it were practical I
would want the same gain on seventy centimeters that I have been
getting out of the dual stacked half wave on two meters. The
available testing that I was able to find says that it is 6 DB over a
quarter wave vertical. What I would happily settle for would be for
it to have the same gain on seventy centimeters as the dual band
simple J-pole I am using now. After talking to Rol Anders, K3RA; who
was the instructor for my Extra theory class and is the present
chairman of the Question Pool Committee of the National Council of
Volunteer Examiner Coordinators (NCVEC); last night I am taking that
later approach. That is the approach that I outlined in the first
paragraph of just putting an open blocking stub for UHF at thirty five
centimeters ~ up the lower two meter half wave and therefore below the
two meter phasing stub between the two meter half wave segments. That
has the virtue of being simple and still giving me a dual band antenna
that has better gain on UHF then the unmodified two meter antenna
would.

I wanted a dual band antenna because I only have three suitable
mounting points on my home and I already have plans for a six meter J-
pole and an anemometer / sensor array assembly on the other two. I
have an Arrow dual band J-pole up on that mounting point right now but
I wanted to return to the higher gain of the collinear dual half wave
J-pole that gave me so much better real world performance on two
meters. It is my hope that just adding the seventy centimeter band
blocking stub to the collinear antenna's lower two meter half wave
segment will do the trick.

--
Tom Horne, W3TDH