On Wed, 27 Feb 2008 17:21:01 GMT, "Barrett"
wrote:

Question about the elements.

Does the speaker wire need to be kept very straight (no twisting) or doesn't
it matter if there twisted?

Ok Dave, I will see what I have in the shed.
Trouble I have is that I only have a SWR meter to do the tuning and I
have heard the thickness of the wire can change the length of wire used by
quit a lot. So I really needed to get it very close for the tuning as I
don't have an analyzer to use.

For wire running in a zip cord, point-to-point, you will use more wire
by twisting than running straight. This will affect the tune if, as
you say, length is critical.

As for being critical; there are many variables that contribute to the
state of tune, wire length being one of them, but not the sole
variable. The presence or absence of insulation, and how thick it is
will be another variable. Proximity to other materials in the
construction will be yet another variable. Proximity to other
environmental disturbances will contribute more variables. You are
almost guaranteed to not be resonant the first time.

Your SWR meter is sufficient for the purposes of tuning your antenna.
Simply take readings at close frequency intervals to chart a curve of
match (or mismatch as the case may be). Do this with the antenna IN
PLACE. Note from this curve how much you are off your desired
frequency. Make a slight (emphasis on slight) adjustment and repeat
the curve building exercise with the antenna IN PLACE. You will now
have a reference (the first curve) and a delta (the difference between
the reference and your second curve). This should tell you how much
you need to adjust to achieve match.

73's
Richard Clark, KB7QHC