> wavelength feedlines as well. The current forcing that
occurs with odd multiples helps to preserve stacking
performance even though the antennas being stacked might
have slight differences
> in feed point impedance across their respective
bandwidths.
Everyone should always remember that current forcing does
not always work properly unless the antenna is series fed at
the current maxima. In other words if the feed system of the
element isn't right at current maximum point or if it
involves a transmission line like a shunt feed or gamma /
omega match.... an odd 1/4 wl line feeding that point from a
constant voltage won't force equal currents.
The extreme is with voltage (end) feed. Equal currents
requires equal voltages at the feedpoint. But even gamma's
can hose up how the system works, and require something
other than odd 1/4 wl lines for forced equal currents.
Just something to keep in mind.
73 Tom
_______________________________________________
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Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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