NVIS

Near vertical incidence skywave planner

Estimate take-off angle, MUF and recommended dipole height for close-range HF coverage.

Target range (km)

F-layer virtual height (km)

Critical frequency f₀F2 (MHz)

Typical daytime F-layer heights range 200–350 km depending on solar conditions.

Aim for take-off angles above 70° for reliable NVIS coverage within a few hundred kilometres.