| 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.
Thanks!
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