I have acquired additional information re the KGNM 1270 AM Broadcast Transmitter here in St. Joseph: It is a 210', Rohn 45G, with an excited series wire antenna running along the 3 legs of the tower. Overall true radiated length is 185ft, it is top loaded/ground quarter wave antenna, it runs 89 ohms impedance  @ 1.0 kW power. The reason it is not running at ~50 ohms because when a 1/4~ antenna is top loaded, it tend to radiate more horizontally instead of the more traditional 1/4~ donut pattern. This allows the station to send the signals more across in the horizontal pattern instead of wasting it free air space. The horizontal pattern generates more a ground wave signal, which is the best method for AM broadcasting than sky wave signals, especially at night.


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