Which modified vector Eddie ?
My original tests on 27mhz years ago at more than 1 location certainly changed signals as I described,
I now think I was finding a sweet spot where what I lose through extending the monopole was more than compensated by the extra height over obstructions, up to a point,
The original 7/8vector was still too long for best results & I never extended the cone longer than just over 90" , shortening the cone to less than 90" hurt performance,
The latest tests done on 50mhz are using full size 1/4wave cone & 3/8wave cone & are not obstructed behind anything in the first mile or so,
but I have only used 2 stations for testing when more in different directions would give a better picture,
in both cases the 3/8wave cone version performs a little worse than the 1/4wave cone version,
its easy to see & consistent when viewed on the rsp1a meter but not on a LCD bar graph radio meter,
Its not just that the performance is not as good, the 3/8 cone creates mechanical issues on 27mhz too,
using fewer sections of the thickest wall strongest grade tube does not make the best antennas,
It makes very heavy & expensive top heavy antennas.
