We all know that our 100 mW AM signals do their best during daylight hours but get swamped at night when skywaves come pounding. Imagine this: suppose the FCC rules allowed a power increase after dark that would make our coverage footprint about the same as the daytime.
Without experimentation we have no way of determining how much power it would take to achieve. Maybe testing with longer antennas could tell us a little, but our transmitters are optimized for 3-meter antennas and might not perform properly with longer antennas. Nor can our transmitter power be increased for test purposes.
I'm sure they would allow power increases at night, as long as its radiation doesn't exceed 24000/F(kHz) microvolts/meter at a distance of 30 meters. But that would be a decrease wouldn't it?
You said: "..but our transmitters are optimized for 3-meter antennas and might not perform properly with longer antennas..."
I can't see you, did you say that with a straight face?
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