I did a spectrum test on that 4:1 DX ENG 5kW Balun.
https://www.dxengineering.com/parts/dxe-mc20-v4-1 I did a DC GND continuity test and measured 1.6 Ohms. Not bad, but I did look inside, and I didn't really like how they 1/2 soldered the connections inside, so I silver soldered them with the 140W gun. Passed DC GND tests at just .6 Ohms. Then, I took two 100 Ohm, 1/2W, resisters, (For 200 Ohms.), and tied them to the Dipole bolts. Then used my MFJ-269Pro ANT Analyzer and spanned from 1740kHz to 180MHz. WOW!!!! Solid, flat, 1:1 VSWR from MW to around 27MHz, but 11M and 10M were still a 1.1:1 match. Then, curved to 1.2:1 about 63MHz, and was still that all the way to 2M, which was a 1.3:1! Then, the curve raised about 1.5:1 around 158MHz. Damn!!!!! Now that's wide banded! Anyone ever put one of these Baluns up on a Dipole, or a Longwire? For over 25 Years, I've used the W2DU 4:1 Current Choke Balun, running barefoot power, with nice results. However, I believe that the power rating of that is 300W. The 5kW rating on the new Balun is certainly overkill, but at least 500W won't be a problem.