Resonance has no effect on antenna performance so it¡¯s not
a concern if an antenna is resonant or not. I don¡¯t think I ever saw an US AM broadcast
antenna that was resonant.
It's not just US broadcasting stations that are like that, in France too. I did part of my out-of-school internship at a station that was broadcasting
300 kW on 600 kHz
150kW on 890kHz
All in AM, modulated screen plate so x4 for PEP.
The antenna was a 40 m high radiating tower, guyed, supported by a large insulator. Each of the two transmitters came via a 135 ¦¸ pseudo coaxial (in wires) to a small cabin where there was a plug at each frequency which served as a duplexer and a series choke to compensate for the residual capacitance. The pylon was far from the ? wave
When we study an antenna project on EZNEC, we can clearly see that the resonance only acts on the impedance and quay only on the reactive. The real part of the impedance varies little in the vicinity of the resonance
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F1AMM (Fran?ois)
-----Message d'origine-----
De la part de Ray
mercredi 10 ao?t 2022 16:40
