> Don't ALL antennas have some amount of standing waves?
Yes.
> What must be done to
> measure accurate resonance?
Remember when a feedline has standing waves reactance
varies along the length of the feedline. It's only at exact
1/4 wl multiples that reactance at the antenna would have
the same value. At odd 1/4 waves the sign reverses. At even
1/4 waves the sign repeats.
You can know the R and J (including sign) and loss of any
length line and back out the real value at the antenna.
Without doing that (or having a line and exact multiple of
1/4 wl) we really don't know where the antenna is resonant.
I always thought one could set resonance first>
You can. At the feedpoint of course.
> then work on matching to get low VSWR.
Low SWR is always low SWR so long as the instrument we use
matches the impedance of the transmission line. If we use a
meter properly normalized to 50 ohms on a line that is 50
ohms, the SWR reading will be correct for the insertion
point no matter how long the line is. If the feedline is 60
ohms and the meter set for 40 ohms, the reading isn't the
actual line SWR at the point where the meter is inserted.
SWR is different than resonance.
73 Tom
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