nathan wrote:
I have always heard that this is true, and that I should tune antennas
for maximum field strength and not for minimum SWR. Why wouldn't they
occur at the same time?

I read somewhere that maximum power is transferred when the load is
the complex conjugate of the impedance presented to the load by the
transmission line. I think that was explained in "Transmission Lines"
by Chipman. Minimum SWR seems to occur when the load impedance is equal
to the characteristic impedance of the transmission line. These are not
necessarily the same points if Z0 has a reactive component.

Also, if the field strength measurement is not being made in the far
field, it may not be an accurate indication of far field radiation
which is what matters. Measured near field photons may simply recombine
with the antenna's free electrons and not contribute to far field
radiation.
--
73, Cecil http://www.qsl.net/w5dxp



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Nathan wrote:
"Why wouldn`t they occur at the same time?"

Suppose you adjust the length of a 1/4-wave antenna to resonance. And,
suppose its impedance is 37 ohms. The antenna has no reactance and is
resonant but it does not match the coax in spite of zero reactance
because the surge impedance of the coax is not 37 ohms.

Best regards, Richard Harrison, KB5WZI