What is the approximate maximum range for signals using transequatorial propagation?
Why Transequatorial propagation (TEP) works between stations roughly equidistant north and south of the geomagnetic equator, each up to about 2,500 miles from it. Signals refract off dense, bulging ionization in the equatorial anomaly regions, so the total path length tops out near 5,000 miles. TEP often supports VHF contacts (6 m and even 2 m) around dusk when the MUF along that path far exceeds normal predictions.
Watch out The choice saying 2,500 miles is the distance from the geomagnetic equator to each station, not the end-to-end path; doubling it gives the actual maximum range.
2,500 miles each side of the magnetic equator, so 5,000 miles total.