The more efficient trap verticals have tubing length settings, for each band, that are in the instruction book as nominal and can be slightly lengthened or shortened to optimumize the antenna for your particular conditions of surroundings and radial deployment. THAT AFFECTS THE RESONANCE OF THE ANTENNA.
Using an internal "tuner" has little effect on the performance of an antenna, just fools the final stage of the transmitter into maximum output. The antenna may not be radiating much power.
Tearing down a vertical for a low dipole will get you stronger signals stateside and less DX, generally.
I have both aVertical antenna and horizontal wire antennas to choose from depending on conditions.
FISTS #3853,cc 455
SKCC # 1395,tribune #12
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