Hello Bayous:
Good Morning, Oh four hundred here, way to early, heheheheh
As Moleculo said here, experimentating around is half the fun, of course its also a FCC rule to listen to Rock n Roll, or Country & Western, right? I am sure it is!
Yes the ground plane radials need to be 1/4 wavelength long, and adjustable so that they can be adjusted to where you want them to work. By adjusting the ground plane radial lengths, will change the antennas operating frequency!
Just as the vertical element, which also has to be a 1/4 wavelength long.
When the ground plane radials are working correctly, the differenent antenna heigth, will only slightly change the antennas SWR.
If no ground plane radials are used, then the outter coax will radiate, and again different SWR values will be seen with different mast heigths.
You may want to try a choke, made from 6 turns of coax around a 6 inch diameter, taped into a nice straight and even coil, that is a 1/4 wavelength down from the antennas connetor.
But please let us all know what your results are!!
Jay in the Mojave
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