Start here: Transmission-line current is the combination of forward and reflected waves on the intended conductors, plus any unwanted common-mode current on the outside or supporting structures.
Why this changes a real station
With mismatch, voltage and current vary along the line; their maxima do not generally occur at the same positions. Line loss changes the pattern with distance.
What it looks like in practice
A clamp-on current reading at one point cannot describe the whole differential standing wave or separate common mode without the right fixture.
What to do next
Use line theory, known impedance and electrical length, directional measurements, and common-mode sensing appropriate to the conductor pair.
Evidence boundary
Keep frequency, reference plane, antenna geometry, losses, measurement method, and safety conditions attached to the conclusion. A match, a DC check, or one field symptom does not prove efficiency or identify the complete RF path.
