AM broadcast band antennas 5/8 & 1/2 wave tall are rarely used any more. I noticed a reduction of the tall AM towers starting about the 1960's.
An optimized half-wave design (180-195 electrical degrees) is still the height of choice for AM broadcasters. There are many factors, including financial, land acquisition, etc.- that preclude the use of these optimized radiators, but given the choice, an optimized half-wave design is preferred.
Yesterday, I pointed out that these half-wave designs were preferred since they simultaneously maximize gain at zero elevation while minimizing skywave radiation. It would have been more correct to state that the optimized half-wave design maximizes gain at zero elevation while simultaneously minimizing *high-angle lobes* that are associated with radiators over about 195 degrees in height and that includes the 5/8 wave radiator (225 electrical degrees). It's the high-angle skywave component that's destructive to AMBC listening.
Paul, W9AC
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