Beta-Match for MP-1 and HF-P1 (ready to use)
Under certain earth conditions the length of the coaxial cable is unusually sensitive to the tuning, at the same time the foot resistance at the resonance frequency is in the range of 20-25 Ohm. I could observe the whole thing especially on 40m, but not yet on the higher bands. The solution to use 4 10m long radials is a little reluctant for me, because it counteracts the main advantage of the MP1. I've found another solution that always works in extreme conditions at the first go: A beta match directly to the foot and a mantle wave barrier directly behind it.